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Eleven years ago Robin Lawrence was tapped to lead the charge for EFI at Holley. In between the braps of an impact wrench, the veteran racer from Galesburg, Illinois tells us that itโs a job which has evolved significantly over the years. โSorry, Iโm taking main cap bolts out โ Iโm trying to get some parts out to Michigan,โ he says. โRather than ship parts over there, I need to pull something apart so I can take it with me.โ Now serving as the director of motorsports for the company, the demands of the gig split his time between the drag strip and the office, but itโs clear that the company found the right man for the job.
Lawrence got his start in NMRA competition back in 2000 running Factory Stock after previously competing in the NMCA, and even early on, he sought to find ways to innovate rather than simply following the status quo. โWhen everyone else was doing Vortechs and nitrous, I had a turbo Fox-body,โ he says. โIt was a car my daughter drove in high school โ a little four cylinder that I had converted to a V8 car. She decided she wanted something different, so I repossessed it and turned it into a race car.โ
He pivoted over to the Real Street class a few seasons later before subsequently teaming up with General Motors to help develop and promote their new LSX block. โI had a Nostalgia Pro Street Nova with nitrous for a couple of years, but I really didnโt accomplish the goals that I wanted to achieve with it,โ he says. โBut life moves on, and in 2009 we did a fifth gen Camaro with an LSA crate engine and a 4L80 โ so basically a ZL1 before that combination officially came out, and it ran 10.30s at 4000 pounds.โ
Lawrence came on board with Holley at the end of 2010 and quickly assembled a team of hardcore racers to assist with the EFI motorsport program, which in turn led to Holleyโs involvement with Chevroletโs modern COPO Camaro program, the ARCA racing series, and NHRA Pro Stock, along with efforts in circle track and off-road disciplines as well.
โWhile I was racing Daren Poole-Adamsโ COPOs in 2016, I got to talking with Jesse Kershaw from Ford Racing,โ he recalls. โHe told me about a car that was unfinished and had been kind of languishing โ just basically moving around from one shop to another. It was a 2010 Mustang body in white kit โ car number 004. Watson Racing had already done all of the work on the roll cage and all of the prep to make it a Cobra Jet. I told him I would give the idea some thought, but by the time I called him back about the car, he told me heโd already sold it.โ
Fortunately for Lawrence, the buyer had unrealistic expectations in terms of the costs involved in making the Mustang into a competitive drag car and backed out of the deal a short time later. โSo I jumped on it right away, and over the next few years I pieced together the parts for it while still racing Darenโs COPOs when I had the time. Eventually I just decided that I needed to stop racing these COPOs and get my own car done.โ
After sending the car out to be painted at Turn Key Automotive โ the same shop that paints the COPOs โ Lawrence set to work piecing Cobra Jet Mustang together, sourcing the Strange rear end and various components like the fuel lines, dash pieces, and other Cobra Jet-specific odds and ends from Watson.
โDave Zimmerman from Team Z was involved in the Cobra Jet program at one time, and I had worked with Dave on my Nova previously,โ he notes. โI gave Dave a call and a got hold of the rear suspension pieces I needed from him. I also met Jimmy Ronzello, who had been a Ford test driver for the Cobra Jet back in 2008 and worked in their engine lab. I generally like to do my own engine development stuff, but I knew it would take me a lot longer to get up to speed without Jimmyโs experience with the Coyote engine program. So we started collaborating in 2019, basically sharing knowledge as the car was being developed.โ
In the meantime Lawrence sourced a G-Force transmission along with a twin-disc billet clutch from Charlie Westcott at Militia Racing Products and bolted up a Holley Dominator EFI system, along with a Racepak digital dash. โThereโs a lot of data logging capability in there that you would not normally see in a car at this level,โ he says. โI have data points coming in that guys with cars that are three times as valuable donโt have. Not only is that helping to make the car more competitive, it also helps me improve my knowledge of these platforms in order to provide better support to our customers.โ
The car made its debut at the 2020 Cobra Jet Reunion, though early teething problems with the carโs setup ultimately ended Lawrenceโs weekend early. โI had an issue with the installation of one of my cams and Jimmy showed me the error of my ways,โ he says. โSo we fixed that and made a few more passes before the end of the year. We basically got it down the track enough times to figure out the game plan in terms of what needed to be worked on.โ
Early in 2021, he took the car down to Florida for some seat time at a few NMRA events. โI jumped in on any test sessions that were available,โ he notes. โSeat time is very, very important when youโre going to be racing against guys that have hundreds and hundreds of passes in their Stock Eliminator cars. Rick Jones helped me out with my shock data and we sent the shocks Strange to be dyno tested and re-valved because my shock velocities were way off. In the meantime, I worked with Charlie to get the clutch sorted out โ we tried some different discs, along with different ratios. Iโve got two different G-Force G5R five-speed transmissions with different gear sets, and we honed in on rear end ratios that worked the best with each of them. After that it was figuring out shift points and launch RPMs.โ
Under the hood of the Cobra Jet is a NHRA 2012-spec 302ci Coyote V8. โTo work with the rule set the valve lift can be more than like, 470, and it has to be the stock 2012 intake and throttle body size,โ he explains. โThe camshaft can be any duration, but the pistons have to be NHRA approved โ theyโre about 12:1. The heads are un-ported, you can go with a 50cc combustion chamber, and the headers are off the shelf Hooker Blackhearts.โ The combination puts the car at an NHRA-rated 325hp, which equates to 486 horsepower at the wheels on Lawrenceโs chassis dyno. Peak power comes in at 6800 RPM, but he says he typically shifts between 8000 and 8400.
In Stock Eliminator FS/H the minimum weight is 3258 pounds, while FS/I class rules set that number 3420. โI was able to get a class win with the car at the Sports Nationals in Columbus earlier this year, but that was in an orphan class,โ he quips. โThings really started coming together at the NMRA/NMCA race in St. Louis. The car was set up for FS/H and weighed in at 3280, and because of the wonderful air down there I ran a 10.11 at 135 mph.โ
That was fast enough to become the carโs quickest pass to date, but Lawrenceโs record-setting performance was actually made with the car prepped for the heavier FS/I class. โThe car weighed in at 3430 and went 10.27 at 130 mph at the Fall Classic at Indianapolis,โ he says. โFor FS/I, it was basically an open record โ the minimum to set a record in FS/I would have been an 11.15. Knowing that I could beat that number, I decided test the car at the NMRA finals in Bowling Green two weeks beforehand at FS/I weight. The additional weight of the car meant that I needed to work on my clutch setup. It was pretty warm at that event, so the numbers werenโt stupendous, but it allowed me to gather really valuable data for Indy.โ
Despite a rained-out test day on Friday at Indianapolis, Lawrence managed to break the record on his first attempt the following day. โSo we had two qualifiers on Saturday morning, and you have to claim that youโre there to make a record attempt,โ he says. โThey run you single after everybody in your class in both rounds, so we waited until 80 or so cars were done.โ
The first pass was a 10.34, which was good enough for the record, but Lawrence knew there was more in the car. โWe went back and looked at the data and the air was kind of weird because it had a lot of moisture,โ he says. โI figured since weโd already set the record we basically had nothing to lose, so I made a slight change to the tune up, raised the launch RPM, tightened up the front struts a little bit, and went up on tire pressure. And thatโs when it ran the 10.27.โ
Tech inspection required the team to pull the cylinder heads off of the Coyote, which meant the harmonic balancer, front timing cover, cams, and exhaust needed to come off as well. โThey ran the full gauntlet of tests โ they poured volumes on our intake and exhaust ports, along with the chamber, and they checked the part numbers on the pistons, heads, and the manifold. They also checked dimensions on the bore and stroke, the camshafts, and the throttle body, along with the carโs wheelbase. It was thorough.โ
Lawrence and his team had already decided beforehand that if the car ran the number he was gunning for and was subsequently pulled apart for tech inspection, they werenโt going to put it back together for the race. But he says it is likely thereโs more left in it. โWe went back, looked at the data and said, โoh โ look at this, and that, and that,โ he says. โAs racers weโre all optimists โ otherwise we wouldnโt be putting ourselves through all of this!โ
Although the team has identified some specific aspects of the car that can be further refined, Lawrence is also quick to point out that he doesnโt plan to make too many drastic changes to this proven combination. โStock Eliminator is basically a bracket race โ I do not want to mess with something thatโs predictable and consistent. And so far it has been glorious.โ