Tubular Tales--An Investigative Story
By Jon Asher
Photography, except were noted, by Jon Asher
© 2007 Competition Plus Magazine.
Used with permission


espn2/Motel6 Vision

Understanding The Current Conflict Regarding
Top Fuel and Funny Car Chassis Construction 

This is a story filled with intrigue, personal animosities, political ramifications, obfuscation and denial. 

It’s also a story about potentially saving lives. 

This is an incredibly complex subject, one no journalist currently covering drag racing is probably capable of writing about in a comprehensive manner without assistance.  At the same time it’s a subject that must be covered because lives may be at risk if everything that’s happening largely behind the scenes and out of the public’s view doesn’t become public knowledge.  There are some involved in this situation who would prefer we didn’t take on something they’ll contend we know far too little about.  That may be true – but we know how to conduct research, and we know how to find the individuals capable of answering what might appear to an expert to be naïve questions.




This may be a story about chassis construction, but it’s more. It’s about protecting the sport’s heroes, like the inimitable John Force, from the unthinkable. Force is easily the sport’s most recognizable name and face, and this is where we need him – interacting with his thousands of fans, not in a hospital bed.

 No single incident caught the attention of the drag racing public as quickly and pervasively as John Force’s crash in Texas on September 23rd.  Covered extensively by the cameras of ESPN2, the story was quickly picked up by the wire services and spread nationally.  Unfortunately, the on-camera ESPN talking heads made numerous comments during the re-plays of the accident that had no basis in fact, and resulted in a lot of erroneous speculation on the Internet.  The commentators weren’t really at fault, as they had nothing to go on other than what they were seeing on the screens in front of them, and television abhors silence.

Since then sites like YouTube.com have offered anyone who missed the original coverage the opportunity of seeing every possible video view of the incident.  Commentators and writers have offered different reasons for the crash, but there’s one thing none of them have dared say out loud:  Force’s accident appeared to be an almost mirror image of the accident that cost Eric Medlen his life in March of this year.

Chassis builder Murf McKinney says, “according to John Medlen (the accidents) were very, very similar.”


It’s also possible that John Force Racing was on the verge of what would have then been a second major chassis-related incident at Maple Grove in August when alert crew members spotted chassis damage after Robert Hight’s first round victory during which his car had gone through severe tire shake.  Due to that damage Hight was a no-show for the second round, and debuted a brand new car just days later at the NHRA U.S. Nationals. 


Murf McKinney and his staff came up with additional bracing for the “fix” installed in many customer cars prior to the Tprcp Race Fuels Nationals in Richmond. Look at the renderings carefully and the additional bracing can readily be seen around the forward portion of the chassis where the cage joins the main rails. Renderings courtesy of McKinney Corporation (Renderings courtesy of Murf McKinney Corp.)




There may have also been a fourth incident involving JFR as well, as sources close to the team have told Torco’s CompetitionPlus.com that one of the cars suffered chassis damage during another post-race test, but we’ve been unable to confirm that.

Force cars aren’t the only McKinney-built Funny Cars that have encountered problems.  When we asked one prominent team owner if his cars had needed chassis repairs this year he said, “I’m sure all of them have had to be welded on at some point.”  Tim Wilkerson’s car needed repairs during the U.S. Nationals.  The left, lower frame rail was, in Wilkerson’s words, “Cracked in the weld.  Murf (McKinney) came over and looked at it, and he actually repaired it himself.  He said he sees things like that from time to time, and after the fix he said we were good to go.  I don’t know if that was any kind of chassis-threatening condition, but we looked the car over and found it, and he said it needed to be fixed.  He said he’d help us, but he really did (the repairs) himself.”


Just as he’s in the middle with Graham Light and starter Rick Stewart in this photo, Dan Olson, NHRA’s Director of Top Fuel and Funny Car Racing is in the middle of the chassis construction controversy. Based on his comments to Torco’s CompetitionPlus.com it would appear that he wasn’t familiar with the NHRA rules and/or SFI Funny Car chassis spec until quite recently.


The heart of this issue is whether heat treated 4130 chrome moly (sometimes referred to as “hardened) tubing is fit for use in some portions of Top Fuel and Funny Car chassis, or should these volatile machines be welded together using only Condition N, or “normalized” tubing.


Since there now seems to be some disagreement as to what “normalized tubing” consists of, and to avoid confusion, from here on we’ll stick solely with the term “Condition N,” as that seems to be universally accepted.


Cracking is definitely not a new problem.  The SFI Top Fuel chassis spec (2.3M) currently being used does call for the use of heat treated tubing in some portions of the cars, and has apparently resulted in some incidents that have gone largely unreported.  PRO president Kenny Bernstein sent the following e-mail to the membership on May 30, 2006 – well over a year ago:


“It has come to our attention that very recently a couple of Top Fuel cars have suffered broken or cracked chassis, however this information was not passed on to Ray Alley or NHRA.


It is very important that any team having chassis problems bring Ray up to speed so that he and NHRA have all the information they need to help all teams.  This information will help teams and NHRA know what to look for and where to look, and help NHRA know if the problems were suffered before or after chassis upgrades.”


We do not know what the response of the membership was, or if NHRA took any action as a result of any responses received.


In favor of the use of heat treated tubing is chassis builder Murf McKinney, arguably the largest supplier of such chassis today.  Some have suggested that individuals working for Ford Motor Company also accept the premise of heat treated tubing for use in Funny Cars, but when we contacted Niranjan Singh at Ford Racing Technology, an employee involved with this motorsports project, he suggested we direct our questions to Austin Coil at JFR.  That proved fruitless because the team has repeatedly declined to answer questions regarding the chassis issue.  We sent another e-mail to Mr. Singh, again requesting his expertise, and received the following from Patrick DiMarco at Ford Racing Technology:

Austin Coil (leaning over engine) has significant responsibilities with John Force Racing, including making sure his main man is physically able to race. Our sources report that Coil is having a new all-Condition N tubing chassis built for Force for the 2008 season

 “Ford Racing does not have an official position on the tubing type or material specs.  We are currently learning and coming up to speed as quickly as possible with regard to the funny car.  Our first objective is to make what we have safe and that involves analysis using current materials and process.”

Among those copied by Mr. DiMarco were Mr. Singh, and Kevin Kennedy from one of Ford’s public relations agencies.


Staunchly in favor of using only Condition N tubing are a significant number of smaller chassis builders, including Brad Hadman, Ty Baumgartner, Steve Plueger (multi-time champion chassis supplier to John Force) and Don Long, among many others.


McKinney wields considerable power in the industry for the simple reason that his well-established operation churns out a significant number of cars each year.  Were, for example, McKinney’s cars to be deemed illegal it would put a massive hole in NHRA’s national event fuel fields, something the organization would obviously seek to avoid.  But would they look the other way to avoid that problem?  There’s no way of knowing for sure, but we can’t imagine NHRA or its fans being pleased by a Top Fuel qualifying session with six cars and a Funny Car session with that same anemic turnout.  At Indy, for example, seven of 23 Top Fuel entries were listed as McKinney products, with another four coming from a chassis source considered to be a McKinney clone.  It’s slightly more difficult to discern chassis builders in Funny Car because they’re listed by body style, but of 22 entries a dozen appear to be McKinney offerings.


While each side readily references reasons for their decision-making, it’s important to note that no scientifically prepared papers or documents have been offered by those advocating the use of heat treated tubing to back up their position.  On the other hand, those in favor of using strictly Condition N tubing have a wealth of published works favoring their position, papers written by respected Ph.Ds in metallurgy and mechanical engineering.  Further, the Internet has a significant number of dissertations available that outline the safety reasoning behind the use of Condition N tubing for race car chassis construction, but there don’t appear to be any that outline heat treated tubing as being as “forgiving” as is Condition N tubing.


When Murf McKiney was asked to provide documentation in favor of the use of hardened tubing he referred us to Military Specification MIL-T-6736B.  This document, which is dated 1965 and has since been superseded, merely outlines the necessary properties of both hardened and Condition N 4130 or 8630 chrome moly tubing of various sizes, shapes and dimensions for military use.  Significantly, at no point does this document outline the properties of these materials if they were to be used in race car construction.  It goes no further than to outline what these materials must be for military use.


Somewhat caught in the middle is the National Hot Rod Association, which depends on the SFI Foundation for its chassis specifications, among other things.  SFI, which formerly stood for “SEMA Foundation, Incorporated,” is no longer directly affiliated with SEMA, but retained the alphabetized name for simplicity’s sake.  Regardless, the organization has been loosely affiliated with the NHRA for decades, although each tries, in its own way, to maintain some distance so there doesn’t appear to be any direct interaction between the two when it comes to things like determining chassis and other specifications.

Critically, the 2007 NHRA rule books states under Funny Car, “Chassis must meet SFI Spec 10.1E.”  This is clearly an endorsement of the SFI spec, just as it’s clear that NHRA bears the responsibility for enforcement of that rule.

Numerous theories have already been offered as to the cause of Force’s crash in Texas, but one that we’ll discount immediately is that the foam timing reflector block that opponent Kenny Bernstein hit and sent flying into Force’s lane had anything whatsoever to do with the incident. 


When the front portion of Force’s car struck Bernstein’s Monster Dodge the horrifying possibility existed of the sport losing its arguably two biggest stars. This crash, and its cause, must be a wakeup call for the sport

A frame-by-frame analysis of the various video views of the crash clearly shows the block going behind Force’s car and harmlessly impacting the guard wall.

Some, including chassis builder McKinney, have suggested that the accident was caused by a Goodyear tire failure.  “I am certain that the cause of the chassis failure was the result of the tire coming apart, for whatever reason,” he said. 

Goodyear is still in the process of completing its examination of the Eagles taken off Force’s car after the crash, and while they’ll acknowledge that one tire was deflated, preliminary examination does not indicate a failure.  It’s yet to be determined, but it’s possible that something hit the tire, causing the deflation.  It could have also been deflated as a result of the back half of the car being ripped off when the parachutes deployed following the body disintegration.

In the Medlen accident the Goodyear tires did play a pivotal role, and Goodyear’s engineers have publicly stated that something struck the inside sidewall of one of the tires, resulting in its failure.  The question then becomes, “Where did the object come from that hit the tire, and what was it?”


It’s conceivable, but unlikely, that Medlen ran over something on the track with his front tires, which picked up that object, throwing it to the back of the car, where it struck the inside sidewall.  More likely is that something came off the car and hit the tire, causing its failure.


What can’t be denied is how severely and dramatically Medlen’s chassis failed in his accident.  Observers on the scene in Gainesville report his mechanics being visibly shaken and outspoken in their displeasure upon discovering how many places the car seemed to come apart in the accident. 


In a post-accident-study press conference during which a number of those involved, including NHRA officials, spoke publicly for the first time, John Force said, “We gave John Melvin (from Wayne State University) nothing to go to the labs with except a chassis that was broken into a million pieces.”


In the case of Force’s accident the evidence of a major chassis failure was evident to anyone with a television screen and a set of eyes.  The car simply breaks in half, with the cage carrying Force coming to a rather abrupt halt, while everything from the roll cage forward continued down track to the end of the guard wall.

In both incidents it’s quite possible that the lower elongation factor of the hardened tubing used in portions of the cars simply couldn’t “handle” the stress put on those components by such things as frame bounce oscillation caused by the track surface or possibly, by tire vibrations.

Author, John Asher, and Top Fuel Team Owner, Bill Miller, confer at Pomona in February of 2008. Image: Bill Miller Engineering.


On Friday, September 21st Top Fuel team owner Bill Miller presented a three-page document to the PRO Top Fuel and Funny Car Committee and NHRA officials, including Graham Light and Dan Olson, a document dated August 27th and addressed to the PRO membership. 


Accompanying the letter was a supporting document from Dr. Rory R. Davis, PE, of Convergence Engineering Corporation of Gardnerville, Nevada.  Miller’s letter, broken down into four sections, outlined the current chassis situation regarding SFI and NHRA.  It went on to a similar outline of Funny Car chassis specs, then offered some general points.  The letter ended with a conclusions and recommendations section.

The gist of Miller’s missive was that the use of heat treated tubing in Top Fuel and Funny Car chassis had not been made with any scientific supporting documentation, and that there had been a significant number of chassis failures as a result of its use.  He cited incidents involving both Tony Schumacher and Cory McClenathan, but for different reasons.  According to Miller, in his opinion, the Schumacher problem was the result of the use of too small tubing, mandated by the SFI chassis spec at that time, while the McClenathan problem was the result of the Heat Affected Zone (HAZ) failing from welding hardened or heat treated tubing in that area of the car. 

Again according to Miller’s letter, “There is no provision for the use of hardened tubing in the present SFI Funny Car Spec.  Without explanation the Funny Car Spec mandates normalized (not hardened) tubing…”  Miller continues, “McKinney has admitted using hardened tubing in Funny Car chassis.  Funny Car chassis failures, like Top Fuel, have increased since the use of hardened tubing.”

On April 9, 2006 Miller sent a letter to Arnie Kuhns of SFI.  In it he writes, “Keeping in mind that McKinney has told JFR that the bottom frame rails of their chassis are not normalized SAE 4130 tubing as mandated by SFI 10.1E, please answer the following question: How did these JFR racecars get technical approval?” 

Kuhns did not respond, and in Miller’s words, “hasn’t responded to anything I’ve said or written in the last two years.”  The underlining for emphasis appears in Miller’s original letter.

Dr. Davis has offered two documents, an original outline of his research work dated August 28th, and a follow-up dated a month later.  The document is lengthy and detailed, but some sections cry out for inclusion here.  Following his introduction Dr. Davis writes, “At the time, I found the analysis to date for the design of the (Top Fuel) frame, and the resulting specifications as a result, to be seriously flawed, and the knowledge of loads experienced by the cars not well understood.  There was a need for a complete over-haul of the engineering involved.  Linear analysis of the frame was being used, despite the fact that the important response of the frame was nonlinear, namely tube span buckling.”  (We italicized the previous statement for emphasis.) 

Dr. Davis continued by stating, “A re-engineering effort was initiated with reluctant cooperation by SFI et.al.,” not a particularly healthy situation when one considers these should be strictly considered safety rather than political issues.  Dr. Davis says that “problems with frame failures were likely due to rough track frame bounce oscillations, which have never been considered by SFI et.al. for car design.”  He then suggested some minor tubing additions that would preclude tube buckling.


Cory McClenathan’s crash was caused by, in the opinion of Bill Miller, the Heat Affected Zone of his car having been welded on after heat treating.


FEA, or Finite Element Analysis procedures, have been used in the testing conducted by Dr. Davis and others, and rather than go into such detail as to lose the reader’s interest and attention, we’ll keep things as simple as possible.  The questions surrounding the use of heat treated tubing include - What changes to the tubing does heat treating produce? and At what point does heat treating eliminate the durability of that tubing?  Another appropriate question is - How much quality control has gone into the heat treating process?


This latter question is particularly important, because the vast majority of heat treating operations are conducted by hand, i.e., someone manually inserts tubing or whatever’s to be treated into a furnace, checks the temperature to make sure it’s correct, and then removes and quenches the material at what’s hopefully the right time.  But, what if the guy removing the tubing from the furnace stops for a puff on his cigarette or swallow of his coffee, and inserts the tubing in the quenching liquid two minutes after it should have been inserted?  Such a human error – certainly a possibility – would completely negate and/or alter the value of the heat treating process.


Even if the heat treating process is more “controlled” than our outline, someone must still manually set the temperature and “cooking time,” and an error in setting either of those parameters could result in tubing that doesn’t have the properties its end user was seeking.


Batch testing of heat treated tubing is a time-consuming but absolutely necessary process to insure uniformity across the entire tubing order.  That means testing each end and the middle of the first tube to obtain baseline numbers, then performing enough similar tests to insure across-the-board quality control.  By “enough similar tests” we mean that after the each-end-and-the-middle test of Tube #1, and then Tube #2 you could probably go to Tube #9 for your next evaluation.  The bottom line is that with, say, an order of 100 tubes 1 1/2X.065 wall 10 feet long you’d have to check 20 to 30 individual tubes.  More would be even better.


According to our sources who studied the data provided by SFI after McKinney had provided induction hardened tubing samples for evaluation prior to building his 2007 cars, there was a considerable variation in elongation properties.  The standard deviation is 18% of the average.  In the words of our source, "That is huge, and is a good example of the engineer's/statistician's definition of an ‘accident just waiting to happen.'"


Similar samples from a different source allegedly provided to SFI for evaluation by Brad Hadman had a coefficient of variation of 5% or less.  Samples provided by and tested for builder Ty Baumgartner demonstrated a coefficient of variation of 6.2% when samples from the SFI and CEC tests were combined.


Elongation is of critical importance, because race cars are constantly flexing, twisting and bending in ways that we can only imagine – or try to replicate on a computer.  “Seeing” those twists is impossible without serious instrumentation, but one thing does appear to be certain:  Minimum elongation properties for chrome moly tubing should be a minimum of 10 percent of the length of the tube in question.  Simplistically, a piece of tubing 10-inches in length should be flexible enough to stretch an additional inch without breaking.


Correctly heat treated tubes can produce somewhat greater tensile strength, but that additional strength comes with a commensurate amount of lesser elongation.  In testing, a heat treated tube may exhibit greater tensile strength, but when it reaches the failure point it does so rather abruptly.  A similar Condition N tube will flex and bend and also ultimately fail, but when it does so it will, in the vast majority of instances, remain in one piece.  A bent and misshapen race car frame is certainly safer than one broken into numerous pieces.

Dozens of scientific papers have been written about the lack of elongation that’s present in heat treated tubing.  According to some sources the use of induction hardened tubing is a mistake because such tubing lacks the necessary elongation to reach the acceptable level of elongation before failure.  It’s also been proven scientifically that hardened tubing, whether properly or improperly heat treated, becomes more brittle and fracture prone than Condition N tubing.  The brittlization of this tubing is of major importance.  Brittle, inflexible tubing will absolutely fail in terms of structural integrity at lower deflection than Condition N tubing subjected to the same stresses.


Bill Miller’s Top Fuel entry, driven by Troy Buff, is a regular in NHRA POWERade Series competition, but it’s Miller’s aftermarket hard parts business that has earned him the respect of his peer group. When he speaks, people listen and pay attention.

Chrome-moly tubing has been used in aircraft construction since before World War II, and with all of the government’s resources directed towards winning that war the best minds the nation had to offer were brought on board in various capacities, including airframe evaluations.  The result of the scientific work on air frame construction was that only Condition N tubing was used.  Consideration of the use of heat treated or hardened tubing was quickly abandoned because every test conducted resulted in early failures due to a lack of elongation of the tubing.  The testers understood that failures on grounded test stands would be inconsequential compared to the vibrations a combat aircraft would encounter once airborne, thus the determination to use only Condition N tubing.  Simply put, heat treated tubing was too brittle and fracture-prone for use in the “vibration factory” that is an airplane. 


What, if not “vibration factories,” are Top Fuel dragsters and Funny Cars?


The current SFI specs for Funny Car (10.1E) and Top Fuel (2.3M) both begin with the same sentence:  “All structural material for the roll cage, rear-end mounting, and suspension mounting must be normalized SAE 4130 chrome-molybdenum steel (SAE 4130N) purchased to the requirements of military specification MIL-T-6736B and its subsidiary documents or equivalent.”  The question then becomes one of definition.  Does the word “equivalent” mean that the documentation must be equal to that of the military specification, or does it mean the tubing needs to be equal in properties to the 4130N? 


If, as is likely, “equivalent” means tubing of an equivalent nature, that tubing would have to have the same chemical makeup, yield, tensile strength and elongation characteristics attributed to Condition N tubing.


Heat treated tubing, by its very nature, does not have the same characteristics outlined above as does Condition N tubing of a similar size.  We’ve been unable to come up with anyone with any legitimate expertise, either in terms of practical experience or educational background, who will go on record saying that heated treated tubing is the equivalent of Condition N tubing.  Our search for corroboration included chassis builders, Ph.Ds in metallurgy and even a contractor supplying defense materials to the government.  None would agree that heat treated tubing is the same as – or “equivalent” to Condition N tubing.


There’s an ancillary safety issue in play here as well.  Numerous observers have reported that the titanium tubular “trees” used to mount Funny Car bodies show some very interesting heat marks.  It’s been reported to Torco’s CompetitionPlus.com that blue heat marks from welding is evident on some cars as much as 3- to 4-inches from the welded tubing joints.  Colorization such as that is an indication of improper welding, usually the result of oxygen contamination.  In order to properly weld titanium the air inside the tubes must be inert Argon gas.  In fact, the entire atmosphere in the welding “arena” should be Argon, with the operator wearing the appropriate breathing apparatus.


Regis Gully, the owner of Trick Titanium, and the acknowledged expert in drag racing on titanium, says that no indication of heat should extend further than ¼-inch from the welded joint.  Anything beyond that indicates a contaminated weld, one that’s likely to fail. Others report that the aircraft industry will accept titanium welds that have a straw-colored appearance, but anything showing blue must be discarded as a potential failure point.


Robert Hight is the lone JFR competitor remaining in the Countdown, but chassis problems like those encountered in post-Richmond testing don’t do much to encourage confidence by this quality young driver.

Why are we mentioning this?  Eric Medlen’s car hit the wall during eliminations on Sunday at the Gatornationals, and observers on the scene report that Monday morning the team had considerable difficulty getting the body to properly mate with the chassis.  Could it be that one of the titanium tubes underneath the body broke completely off during the run, and that’s what pierced his Goodyear tire?  We will probably never know for sure – but it’s a possibility.


Some years ago Louisiana chassis builder Chuck Haase became increasingly concerned about driver safety after watching a series of televised crashes, including one involving Gary Scelzi in which his car J-bent in half after a tire failure.  Haase concluded that the skid blocks mandated for the chassis were mounted in the wrong place, and would increase the likelihood of chassis failure when the tire failed. The skid blocks would simply move the axis or “pivot point” forward, making the moment or “lever” longer.  In order to prove his theory as well as to test chassis themselves for flexibility he built a massive fixture and did some initial testing with it.  He and a friend then traveled to the U.S. Nationals where he had a meeting with Ray Alley, then in charge of Top Fuel and Funny Car racing for NHRA.  He outlined his “test bench,” showed Alley the photos he had, and told him that NHRA was free to use the device in any way they saw fit.  According to Haase and the friend who witnessed the exchange, Alley was interested in seeing the device utilized by NHRA to test the safety of chassis but Haase never heard a word from him or anyone else at NHRA following his visit to Indy.


A few years later Haase contacted Bill Miller and explained his device.  Miller had it shipped to Nevada where Dr. Rory Davis heavily instrumented it for chassis testing.  Brad Hadman provided a chassis that had been raced in 2006 for the initial testing.  The frame included small support tubes that Hadman had installed to eliminate the buckling potential of the lower back half tubes.  When the frame was extremely over-loaded the “wing stand,” a fixture to duplicate the presence of a wing, failed spectacularly.  The frame itself didn’t completely fail, but there was severe and permanent tube bending behind the engine location.


The tubing that failed had been hardened, i.e. heat treated.


The second phase of the testing was completed with a Condition N tubing chassis built by Hadman to the same weight, flexibility and strength of the first chassis.  As expected, the strength and stiffness were shown to be virtually the same as the hardened version, but with no risk at all of poor elongation material.  According to Dr. Davis, who conducted the tests, “…the frame was so tolerant that in our over-load test the rear differential ripped out of the frame before we got much bending in the back half tubes…”

John Force was concerned enough about what he’d gone through in Texas to have called chassis builder Steve Plueger in California from his hospital bed to ask his former supplier if he would be willing to build him as many as nine new cars.  As Plueger said, “You know how John is, and he was bouncing around on a lot of subjects, so I can’t say that he wanted to order that many cars, but he talked about it.  I told him I wasn’t interested.”  Plueger, now 63, is more desirous of heading into retirement than he is in building more cars.  But he did say that Force prominently mentioned how he’d never had a problem with a Plueger car, and that’s why he wanted another one. 


Tuner Jimmy Prock was outspoken about the chassis problems his car encountered in Virginia – before he was silenced by the team.


Plueger also reports that in his desire to locate as new a Plueger-built car as quickly as possible, Force or his employees tracked down a Funny Car built for Canadian Todd Paton.  The plan was to have someone pick up the car in California (don’t ask, we don’t know why it was out there either), truck it to Force’s shop in Indianapolis, where its GM body would be exchanged for a Mustang, and then blast off for the Torco Race Fuels Nationals in Richmond.  But, when Plueger spoke to driver Robert Hight early in the week of the race he was told the plan had changed, and that the team would accept the chassis changes as recommended by McKinney.


We made numerous attempts to contact members of John Force Racing for their input on this situation, and were unsuccessful.  As a team insider put it, “No one wants to talk for fear of offending some of the people who are trying to help us with this project.”


The heat treated vs. Condition N tubing controversy has also apparently taken a political turn in the makeup of the SFI chassis committee.  After a vote was taken regarding the issue, six members of the committee were replaced by four others by Arnie Kuhns of SFI.  Among those removed were Dave Uyehara, Marc Rowe, and Richard Earle, all of whom had attached notes to their ballots asking for additional time and study before a decision was made regarding the use of heat treated tubing.  Bob Meyer, Don Long and Geoff Houser were also replaced.  Added in their places were Ty Baumgartner, who supports normalized tubing use, Chuck Lett of Attac Race Cars, who votes consistently with McKinney, Hadman, and Mats Erickson from Europe.


McKinney told us Long was removed from the committee “because we thought the committee should only include those who had a dog in the hunt,” meaning someone who actually builds cars competing on the track.  Bill Miller Engineering is a Long client, so the question on this issue becomes - How many cars must a builder build to be considered “having a dog in the hunt?”


Arnie Kuhns of SFI disputes the characterization of the change in personnel in the chassis committees as “arbitrary,” the term used by some of those replaced. 


“They weren’t totally replaced,” he said.  “What happened over time is that committee increased in responsibility from only two specifications to close to 10.  The workload became quite extensive for that committee, and it further became obvious that we had people not dealing with cars with which they had the most knowledge.  In addition to that we had people who were not involved in the process who, quite frankly, were very much involved in building the cars.  A case in point would be Brad Hadman.  Hadman was, and I guess he still is, building about half of the cars that were racing, and he wasn’t on the committee.  That clearly was not right.  Basically, we said if you hadn’t built a Top Fuel car in a year, you weren’t really an active builder, and if you had built a Top Fuel car in a year you were an active builder, and that then defined the Top Fuel committee.  Each group now represents the cars they’re most familiar with.”


Kuhns acknowledges that the use of heat treated tubing is in the Top Fuel specification, “but is not in Funny Car.”  To make sure we completely understood his meaning, we asked, “So in your opinion the use of heat treated tubing in Funny Car would not be in agreement with the SFI spec?”


Tim Wilkerson confirmed encountering a chassis problem during the U.S. Nationals, one that was personally repaired on site by builder Murf McKinney.


“For Funny Cars, that’s correct,” he said, adding, “You understand, I (meaning SFI) do not enforce the spec.  It’s the same with all of the (approximately) 100 specs we have.”  Simply put, SFI is not an enforcement arm.  In fact, the organization goes to some lengths to emphasize that they create no specifications per se, but rather depend on the committees they’ve formed that are supposed to have expertise in their respective areas to come up with those specs.  SFI then endorses them.  It’s their version of the old “Good Houskeeping Seal of Approval” without which some housewives wouldn’t purchase a domestic product in years gone by.  SFI’s endorsement lends a certain degree of credibility to an item, be it safety or performance oriented.


Enforcement of the SFI spec, then, is the responsibility of the NHRA, which, in turn, can have only one meaning:  NHRA has allowed cars that have not been built to the SFI Funny Car chassis specification to compete in the POWERade Series with impunity.


Fact:  The SFI Funny Car chassis spec does not call for the use of heat treated tubing.


Fact:  McKinney Corporation’s owner, Murf McKinney, has publicly stated he’s used, and continues to use, heat treated tubing in Funny Car chassis construction.


Conclusion:  NHRA, despite knowing about the use of heat treated tubing, and despite their own rules that demand strict adherence to the SFI chassis spec, has allowed this to continue, with their logic apparently being that the word “equivalent” in the spec allows a builder to substitute the called-for Condition N tubing with heat treated tubing of greater dimensions.

Dan Olson, NHRA Director of Top Fuel and Funny Car Racing, was contacted for the organization’s stance on whether or not the use of heat treated tubing is permissible or appropriate in Funny Car chassis design. 

“I can’t answer that,” he said.  “This is something I’ll have to look into, to be honest with you.  I thought that spec got changed when we were able to use heat treated tubing on Top Fuel cars years ago.  I can’t answer that, how’s that? 



“I walked into a lot of what’s coming down the pipeline right now, and that’s the reason why I’m investigating. This has been since John (Force’s) incident and Eric (Medlen’s) problem, and I’ve been investigating numerous metallurgists trying to come to some kind of conclusion myself, but there is such a mixed result of opinions, especially with metallurgists, and aircraft hands-on people with mixed opinions that that’s why I can’t answer right now.


“We’re doing some tests, some physical tests, actually on both materials to find out what is the best.  I read Dr. Davis’s paper, and if you read it carefully he left a lot of things open.


“I was in the meeting in Atlanta, and my role with NHRA is not to jump to conclusions.  I was there to accept the recommendations from SFI.  That was the first time I was involved in this.


“We’re working as hard as we can on this, but we’ve got to make sure that what we come up with is the right answer.  I just got off the phone with an airframe engineer that’s been doing this for 25 years, and he would recommend heat treat.  I’ve got about three other hands-on engineer metallurgists who recommend heat treat.  I can find as many or more who would favor heat treat versus Condition N.”


When we asked Olson about the SFI Funny Car chassis spec and its relationship to the NHRA rules, he said, “I’ll have to look into that.  Remember, our stance and my stance is that our Number One thing is safety.  I don’t care if these cars are made out of whatever, electric weld tubing, it doesn’t matter.  Safety is our Number One concern.  We aren’t dragging our feet, we just don’t want to make a wrong decision.  We want to make sure that what we come up with is the right answer.  I’ve been working on this from sunup to sundown, seven days a week for a long time, and I don’t have all the answers yet.”


The day following our conversation Olson called back to state that the SFI Funny Car spec (10.1E) does allow the use of heat treated tubing because of the inclusion of the word “equivalent” and the term “minimums.”  He also promised to forward documentation in favor of the use of heat treated tubing.


Three days later Olson submitted a six page letter attributed to L. Daniel Metz, Ph.D, in support of the use of heat treated tubing.  Along with openly dismissing much of what Dr. Rory Davis has said, Dr. Metz offers statements that have been refuted by numerous others alleged to have similar expertise in metallurgy. 


Drag racing must never come to “accept” tragedies like the loss of Eric Medlen in March of 2007. To do so would be an insult to the very things this young man stood for.


Among other statements in Dr. Metz’s letter, he writes, “Even a rudimentary calculation of tire forces applied to the chassis during a tire failure shows that the loads generated under such conditions are far, far greater than the design loads to which the chassis was designed and built.  The recent Medlin (sic.) and Force F/C accidents were both catastrophic and both were initiated by a rear tire failure.”


Later he states, “In the case of many race accidents, certainly in the case of the Force and Medlin (sic.) accidents, the tire failures involved suggest that the chassis tubes that failed did so because of the accident, and did not initiate the accident sequence.”


Dr. Metz told Torco’s CompetitionPlus.com in a taped conversation, “I have looked at the Medlen car and photographed it in great detail, and I’m going to look at the Force car this week, but other people have looked at it before me.  But, certainly for the Medlen accident and, I have been told, for the Force accident, there is no evidence that the structure failed first, thus initiating the accident.”


As previously reported, Goodyear has said that in the Medlen accident one tire was punctured by something hitting it on the inside sidewall.  They have made no ruling to date in the Force incident. 


Dr. Metz offers no explanation in his letter as to how he concludes both accidents were the result of tire failures, so we asked him about that. 


“That’s what I’ve been told by Dan (Olson) and by the chassis constructor as well.  I looked at videos of both of them, and I don’t think there’s any question about Medlen’s.  The video I saw of John Force’s accident was a head-on video, so I didn’t get a good look at that, but both Dan Olson and Murf McKinney, who built the chassis, (and) I talked to both of them, and they both said that they thought that accident was initiated by rear tire failure.”


Dr. Metz further suggests that, “A successful chassis could be made from either condition N or heat treated 4130 chrome-moly tubing – or from 6061-T6 aluminum for that matter – provided that the chassis is correctly designed and constructed with care.”


On October 2, 2007 we received an e-mail from Murf McKinney in which he states that Dr. Metz is on retainer to McKinney Corporation: “We also retain Daniel Metz, Ph.D., P.E. who is retired from the University of Illinois, as a consultant.”


The web site ALMEXPERTS.com, “your source for experts, consultants & litigation support services,” lists L. Daniel Metz, Metz Engineering & Racing as available for hire as an expert witness.  His profile reads, “Specialize in vehicle dynamics, vehicle aerodynamics, and accident reconstruction.  Have worked for every major auto manufacturer, insurance company and racing organization in the world.”


During our conversation with Dr. Metz we asked him if he had ever worked for either the NHRA or NASCAR, either under contract or as an employee, and he responded in the negative to both questions.  Both are considered major racing organizations, yet Dr. Metz has worked for neither.


Further, when we spoke again with Dan Olson he expressed surprise at being told of Dr. Metz being on retainer with McKinney Corporation.


Discovering heat treated tubing during the inspection process may be somewhat problematical.  Although some experts contend that heat treated tubing is slightly darker than Condition N, that color difference can be negated by lightly sanding the tube or wiping down the entire chassis with an oil-dampened rag.  A portable Rockwell Hardness tester would probably get the job done, but regardless of what’s needed, at this point it would appear that no effort is being made to either discover the use of heat treated tubing in Funny Cars, or discourage its use.


In regards to the chassis fix rushed into use for the Torco Nationals, one chassis builder probably put it best when he said “It’s nothing but more mass to cover your ass.”  In other words, it weighs more, it looks effective, but it’s still utilizing heat treated tubing in places where it’s been proven ineffective up to now.  And any fix may be better than none when it comes to potential legal actions somewhere down the road.


McKinney told us that the chassis fix added to a number of cars prior to Richmond was designed to offset the massive vibrations that might be caused by an out of balance tire situation, but others have suggested this problem may be more basic.  It could be the result of the materials used in the original chassis build – heat treated tubing.


This is far from over. 


On the day following the Torco Race Fuels Nationals, Robert Hight’s car, fresh from the addition of the chassis “fix” at McKinney’s shop, suffered a chassis failure during testing. 


“It cracked a couple of frame rails by the rear end,” acknowledged crew chief Jimmy Prock.  “I don’t honestly know why it happened,” he continued.  “I have my opinions, but I don’t know for sure.  I think I know what happened, but I believe it broke because of what we did (to fix the previous problem).  When it shook the tires it bent something else.  Yeah, I believe that.  I have some ideas on all of this, but I’m not going to say.”


In the aftermath of the Hight incident in Virginia sources at John Force Racing have confirmed that the team will go ahead with the purchase of a new, never-raced Plueger-built car, the Todd Paton car referenced earlier in this story.  The car is slated to be the back-up for Robert Hight, but it’s clear that side-by-side testing comparisons are going to be made.  JFR has previously acknowledged their long term goal of building their own cars in-house.  Evaluating the Plueger chassis could be the first step in that direction.


Interestingly, despite the reluctance of anyone from John Force Racing to discuss any aspect of this scenario, we’ve received a copy of an e-mail that crew chief Austin Coil forwarded to 16 people, including drivers, tuners, Niranjan Singh of Ford Racing Technology, and both Graham Light and Dan Olson of NHRA.  It’s titled “Real World Elongation” by Coil.  Rob Wendlend, the JFR employee who conducted this test, confirmed having done it, but refused to add any further comment.  Here is the entire text of the e-mail:


Sent: Friday, October 12, 2007 6:02 AM

Subject: Tubing Tests


As most of you know I have been trying to develop a "Real World Elongation" test. Our first efforts were to weld stub of 1.5" X.065 tubing to a leg of 1.5"X.065 tubing. We anchored the leg in a big lathe and put a pipe over the stub 6" from the weld and applied pressure until failure. We measured how far the various materials moved before failure.

This is what happened. The following is a quick description of each test.

Test 1:

Normalized Stub and Heat treated tubing leg.  Deflection 23" before failure


Test 2

Normalized Stub and Normalized tubing leg.  Deflection 19" before failure


Test 3

 Heat Treated Stub and Heat Treated tubing leg.  Deflection 11" before failure


The distance from the pointer on the scale to the weld is 57.5"


Any questions about how the test was performed please call the man who did the testing.


That’s the entire text of the message with the exception of a short paragraph regarding shipping a video of the test and a private phone number.

Some chassis builders, apparently concerned about the use of heat treated versus Condition N tubing in race car construction, did an unofficial poll of the nation’s car builders.  A total of 39 builders were asked for their opinions, with 28 calling for the exclusive use of Condition N tubing, and only two in support of the continued use of heat treated chrome-moly.  Nine others either couldn’t be reached or declined to participate. 


John Medlen continues to lead the on-going safety efforts being headed by John Force Racing and Ford.


It should be noted that of the 39 builders polled a substantial number must be considered largely inactive in terms of building cars currently competing.  But, with that said it should also be noted that the list includes drag racing’s A-list constructors of the last two decades.


A similar poll was taken of the 11-member PRO Board of Directors, with nine in favor of Condition N tubing and only one in favor of the use of heat treated tubing, with one other declining to offer an opinion.


The issues of chassis construction methods and driver safety go hand in hand.  Despite the comment of a prominent NHRA official in a meeting with team owners on Friday at the Dallas race – two days before Force’s accident -- that we will have to accept fatalities as a part of drag racing, this is clearly a matter of major importance that needs further and immediate study.  There’s simply no other choice.

Bill Miller Engineering would like to thank author, Jon Asher, and Competition Plus Publisher, Bobby Bennett, for making this article available for posting on this web site.


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