Insane Street Turbo C5 goes 8′s
When you combine a stock-appearing C5 and 8-second time slips, you get our attention. The man is Mike Romain, and he owns one amazing C5 Corvette that has recorded several performance “firsts” with the car. Currently the car is the quickest and fastest A4 transmission equipped C5 Corvette in the country! Even, prior to that mark, it was the first naturally aspirated C5 to break into the nine-second zone with an automatic. The car has an extensive following on Corvette Forum and has had several engine/transmission combinations over the years as it has strived for the 8-second range.
Finally, last November at Atco, NJ, during a test and tune track rental, Mike ran a personal best 8.874 seconds in the quarter mile at 155.29mph — setting the record with a turbo kit from STS Turbo.
When he first started modifying the car, Mike’s first goal was to be the first nine-second street driven C5 in the tri-state area (New Jersey, New York, Connecticut). He accomplished that and the C5 drag race scene became real competitive. “It’s very competitive in this area, we have a lot of shops here and in the beginning no one had ran in the nines.” said Romain. “I race the car locally in the New Jersey Corvette Challenge since 1999 as well as racing it up and down the east coast, I don’t own a trailer, it is a 100% true street car with full interior. I’ve driven the car back and forth to Florida several times, it’s as reliable as a stock C5“.
In late 2002, after converting the car over to an automatic transmission, he dipped down into the nine-second mark with a nitrous set-up. After having issues with the nitrous combo, he switched over to a naturally aspirated engine, a Cartek built, LS6 headed 441ci C5R based engine. “I ran that set-up for a while and then Julio at Cartek asked me to try an Cartek STS 76mm T4 turbo set-up. Cartek has done a lot of R&D on the rear mount STS turbo system for another customer with a GTO. On Mikes project C5, Cartek combined their knowledge of turbos with the STS universal single turbo kit.
“They sold me on the STS, saying that my car could run mid-nines with a very simple set-up using the stock exhaust manifolds. Cartek had a spare turbo around their shop that they installed using STS’s universal rear mount kit. They put the STS kit on my car and it went in the nines pretty much off the bat,” Romain recalled. “After that a lot of people really started paying attention to the car and I ran a personal best 9.33 e.t. at 149 mph.”
Mike credits the performance and drivability to the Cartek tuning/power and the 4L80 automatic built by Rodney atRPM Transmissions in Daleville, IN. RPM built the first 4L60E and current 4L80E transmission and driveline in his C5. Rear end updates include hardened out-put shafts, stock C5 axles, custom RPM transmission brace and RPM built 3:42 gear rear-end.
Suspension updates include; adjustable QA-1 shocks in the front, Bilsteins shocks in the rear. For tires, Mike runs a skinny radial in front and Mickey Thompson Drag Radials on the rear. Mike prefers to not hassle with changing to slicks at the track so he rolls 70 miles down on the drag radials at highway pressures. When he arrives at the track he adjusts them down the race pressure and runs it.
Running with a turbo, the automatic transmission is the hot ticket. Others have tried to talk Mike into running the stouter Turbo 400 3-speed, but Mike has been very adamant about the car being streetable because he wants to drive it to the track. Mike used to own a trailer, but felt driving a car to the track and back would be more impressive. Mike drives 70 miles one way to his favorite dragstrip and that requires an overdrive, thus the GM metric transmission is the perfect street to strip set-up.
Going back to the most exciting part of the car – the nasty turbo — Mike wanted to step it up the power in 2007. The guys at Cartek built a LS-2 based engine and agreed to increase the turbo size to a 88mm T6 turbo. To accent the new turbo, Mufflex Performance increased the size of the turbo plumbing. To handle the new power, RPM Transmissions provided a stouter 4L80E transmission.
Rick at STS has worked closely with Mike on the air-to-air intercooler. His custom built STS intercooler unit is very large and runs frame rail to frame rail to assist in cooling the air charge. Over the 2006-2007 winter, Mike contacted the late Leo Barnaby of Never Lift Racecraft to help modify the transmission tunnel and torque tube to fit the 4L80E. With Mike and Leo in NJ and RPM Transmissions in Indiana, trans parts were sent back and forth to finalize the new set-up. After 3 converters, Mike found Midwest Converters in Illinois to build him the perfect lock-up converter for his unique set-up.
Mike ran the early part of 2008 on a mild- tune and ran low nines. In November of 2008 he turned up the wick to 18 lbs of boost and ran the 8.87 e.t. at Atco, NJ. “I finally got my 3700+lb pig in the 8′s and I did it like I wanted to, on the same wheels and tires I drive on every day, the car was driven to and from the track (145 miles round trip) on my radials”. said Romain.
Mike knows the car has more in it as on the 8.87 run it was running off the TIAL wastegate with the maximum boost at 18lbs without any type of boost control. It was tough for Mike to find the sweet spot at launch so plans for 2009 include an adjustable boost controller.
Weight is the big hurdle with his car. The 4L80 is 100 lbs heavier than the 4L60E and the larger turbo and piping adds pounds. The C5 weighs 3778 lbs with driver. And it’s pretty impressive to see the car move down the track. The C5 has an NHRA certified roll cage and plans are to add a parachute for this year. Mike drives the car as much as possible weather permitting and puts about 7,000 miles a year on it. The Corvette gets over 20 mpg in fuel economy, not bad for a 1,000 horsepower combo.
For 2009, Mike plans to continue racing the Corvette in the tri-state area.
Updates to the car include adding a parachute to help slow the car down from it’s eight second runs. Engine updates will include a boost controller, upgrading the cam to a solid roller, adding a set of custom 1 7/8” shorty headers and a new set of TFS/TEA six-bolt heads. The boost control updates should help stage and launch the car more consistently so Mike can concentrate on driving the car down the track. Once at speed the improved engine performance from the cam, heads and headers should put him solidly in the eights and dip into the mid-eight second zone in the right conditions.