Need for Speed: Hitting the 9-second Pass
LS1Tech reader and longtime auto enthusiast Joe Schneberger aims for a speed record.
The quest to be the first or the best by any large speed shop is expected in the competitive world of high-horsepower street cars. The nine-second cars of today are like the 11-second cars of 10 years ago. But admitting this still doesn’t mean that getting there is easy, not by any means. However, when it came to my newest project, I figured that starting with a car capable of high 10-second passes stock is a good place to start. Obviously, I don’t have many of the resources of a large speed shop, so I was going to have to rely more on my experience over the years with building other cars.
I had fast cars growing up, including a 12-second 1969 Camaro and a nine-second, stripped down 1994 Z28. But as I got older, I no longer wanted lightweight race cars.
So, being a GM guy, the 2017 Chevrolet Camaro ZL1 became the first choice for my next project car. At first, my goal was just to see what this Chevy Camaro ZL1 was capable of in stock form. But it also gave me a place to post and have a common goal with many other ZL1 owners.
The car was fairly new and not many mods were even available yet. I watched some shops do builds then I took the stock car into the 11-flat range at 128 mph. It was very fast for a stock car on stock tires, especially living in Florida and dealing with heat and humidity that many of the faster cars didn’t have to deal with on a regular track day.
Going to the track this way got boring fast because the stock tune on this car is very limiting. It’s torque-based, so even with certain bolt-on modifications or drag radials on the car, the ECM and TCM were keeping it from its full potential. Having a much larger goal and now seeing many shops with heads and cam packages being sold in the 750-850 hp range, I knew it was time to start making changes on the car.
The first and quickest thing was to tune both the ECM and the TCM on the vehicle, knowing from logs that the car was closing the throttle stock. I saw potential in just a tune on it, and after speaking to SkidMark Garage, I discovered that a flex fuel sensor was also an easy way to make power.
My goal was just to see what this ZL1 was capable of in stock form. But it also gave me a place to post and have a common goal with many other ZL1 owners.
Having tuned GM cars since the days of IROC Camaros and computer chips, I decided to tackle it myself even though I had no experience on V8 direct injection. What I did have though was two years of tuning the GM LTG 2.0T 4 cylinder turbo. When the V8 guys got direct injection in 2014, I had already had some time on my 2013 Cadillac ATS 2.0T and was known around the community as having one of the fastest stock frame larger turbo setups, and the guy to turn to when someone needed help with the direct injection GM 4 cylinder stuff.
So, picking up on the LT4 with the help of guys on hp tuners forums wasn’t very hard. My progress on my own tune was quick, and I saw the limits on this build were going to come sooner than I thought due to the stock fuel system.
Though the car ran well on the stock parts and E85 tune, I was now getting power-hungry. So, it didn’t take very long before a list of parts went on order. I didn’t want to copy the typical build because that makes you the typical car. I took what I had learned on earlier builds and the advice from fellow enthusiasts to come up with the car’s current mod list.
I stayed away from cylinder heads and a camshaft. Knowing the flow numbers and potential of the stock parts, I thought the car was very capable of 10 flat in the 137 range, and that became my goal. So, a list was put together and I started ordering parts. I created a budget beforehand, and I decided to look for parts that offered a lot of power instead of going for whatever was the popular choice. Some of these selections included: two-inch headers from eBay with a full off-road three-inch exhaust; five-inch cold air intake; 9.55 innovators; west lower pulley; a larger set of heat exchangers; a 95 mm throttle body from a 2019 ZR1; and an old methanol kit I had laying around from my old Cadillac build.
Though the car ran well on the stock parts and E85 tune, I was now getting power-hungry. So, it didn’t take very long before a list of parts went on order.
I had yet to run the car again at the track. So, it was now time to test what I had put together. I still had the car on an ethanol mix (lower though at this point, down to e50 due to the fuel system limits). Going back in the summer heat, I was no longer comparing it to 11.00@127 but 11.40s@122-123, which is what the car ran stock in the heat.
Going back to Gainesville Raceway and its ailing track, here’s the numbers that were achieved: 10.70@131 and 10.50@132. Scrubbing speed times were not stellar, but I did discover that the low side of the fuel system was now not holding its own. So, it was back to Skidmark Garage and a low side auxiliary was put on the car.
Back at the track the car still was not making the power that I had hoped for. The fuel system had its limits, and fighting a high side pressure issue, I dropped the mix on the ethanol to e30 just to get the logs to look OK and be happy with the numbers I was seeing.
Proof is in the Papers
This time there was a better surface at South Georgia Motorsports Park and I managed two 10.50s@133 and a 10.47@134. But it still was not what I thought the car had in it. At that point I decided it was time to go off the ethanol and try some race fuel.
Using some Sunoco pump 100 octane, and this time making a trip down to a known record-setting race track, Orlando Speed World, I finally was able to click off a decent 1.57 60 foot and ran 10.30@134. It was warmer on this day, and with over 300 cars present, there was no trying to let the car cool off, plus there was a lot of turning the car on and off while working my way up the very long line as the sun was setting.
The car finally ran a best of 10.18@ 136. I had been recently told the record for a bolt-on car had been 10.40@132. So, on this day I bested that by a few tenths, and doing this on my own at a test-and-tune was a proud feat.
Within a couple days, the guys at Redline Motorsports went back to work on the previous record-holding car to add methanol to it. They also spent the day on the dyno to come up with a posted 695 whp setup to yet again try to take this top spot back from me.
I do not know exactly how many passes it took on this rented track day, but with a pile of time slips, a full day of changing the tune and working on it, they managed a 10.04@137 from this new setup. And on a lightweight drag pack, they bettered my time by a tenth and a half.
It could have been easy at that point to just go out and buy some lightweight wheels with skinnys up front and match his setup, which would run around $2,000. I could go back to the track with an easy gain on my side, but I choose to change the old and outdated methanol pump to the newest and best technology that most of the Camaro crowd is now running. That is what the car was lacking, because after the swap, the car went to running a spot on .84 lambda to a rich .78. So, I knew that the change was going to be worth a little more power.
I also went from a 40/60 water methanol mix to 100 percent methanol. With the next track day quickly approaching, I chose to take it back to South Georgia Motorsports Park on a rich tune and make the change there. Not a great day, but not terrible: around 650-700da on a Saturday test-and-tune. Following a two-hour drive to the track and a little cool down, the car ripped off its best 60 foot@1.40 and made a 9.93@138 pass.
The log didn’t look all that great; it had a little spark knock, pulled some timing, and was still rich, so a small adjustment and an hour later it spun to a 1.47 60 foot 6.44@112 eighth and a 10.01@140 quarter mile. The car was making great power, but it was overpowering the tires and lost time.
I had now taken back and backed up the best times posted by a bolt on 6th gen ZL1 on stock heads, stock cam, and stock 1.7 supercharger. Being very happy with the mph and now very close to out-running many aftermarket supercharger builds and cars running larger cams, bigger fuel systems, and ported heads, it has become a goal to attempt to get this car into the mid-9-second range around 145 mph before the Florida weather takes a turn and hits us with 3,000 da days again.
My original plans had been to get to low-to-10 flat and go to a larger, much more efficient pd supercharger, like the LT5 GM 2650. Having port injection on it, the direct injection limited fuel system will no longer be the wall to overcome to making big hp. All my original goals around this vehicle was to build a car I can play with on a road course–possibly the Tail of the Dragon in Tennessee–and still have it rip off mid-150 mph quarter-mile passes while still being a daily driver.
Considering that I am a 25-year master technician who is now 45 and who has been building transmissions for the past 15 years, my life goals are changing. Tuning cars and doing builds is a passion, and hopefully a move to Tennessee and opening a speed shop will be the start to turning my goals into a reality. I have a lot of big plans to try to achieve in the next year, but for now a few more parts and a few more tweaks to get this car into the mid-9s and possibly put a stamp on the fastest stock bolt-on 6th gen ZL1 record.
Check out more of Joe’s time on the track on his lt1z350 YouTube channel.