5 Mods That Stood Out on an SCCA "B Street" Corvette
Here are the top 5 mods I noticed on this Corvette that got the once over for better autocrossing in SCCA "B Street" class. Surprisingly, these simple, streetable, mods make a big difference on the tight, technical, parking lot autocross course.
Let's Autocross the Vette!
A few months ago a friend of mine rang me up and said, “Want to drive the Vette at an autocross?”
“Are you kidding me?” I replied. “Of course!”
And just like that, I was headed for SCCA Solo 2 competition at the big empty lot of asphalt at California Speedway. This isn’t just any Corvette though. The C5 in question underwent a complete overhaul to dominate an SCCA class called B Street (formerly B Stock). Because this is a class for street driven, nearly stock cars, it is a good place to look for hints at where you should start your improvements, even if you never compete.
Bridgestone RE71 Tires
MCS 2-way adjustable shocks
Single adjustable shocks are great, but when they go both ways it’s even better, and for SCCA "street" classes you can't convert to fully adjustable coil overs, so this is it. These adjustable dampers (rebound and compression) make a big difference, but having said that, you absolutely have to know how to tune them, and tune them correctly. This means testing. The shocks in question were dialed in for the car and course, and it was apparent. Turn in was very direct and bumps were handled without any problems. The whole goal here is to get the tire back in contact with the road as quickly as possible, while controlling spring oscillation. This translates to being able to get on the gas really early for better acceleration out of corners, and dropped lap times. Worth every penny.
Alignment
Having a fast car means nothing if you don’t have your caster, camber, and toe just right. This car has been setup custom by a shop that specializes in competition racing alignments. Alignments are not an expensive modification, but they are tune that maximizes the suspension components, stock or otherwise. I could feel the difference in grip coming off of corners, and turning in, very noticeably. It’s all about working that tire and finding the right balance as the wheel steer and the suspension compresses in corners . Check your tires and monitor the wear patterns. This car showed nice even wear characteristics on all four tires and had great traction on corner entry and exit. The alignment is the only mod here that will negatively impact your street driving, because you may wear through tires faster, but it is worth it to have the car aligned before an autocross or track day, and put back to stock specs a few days later.
Strano front sway bar
Here’s the thing about sway bars: the right set will improve everything on a vehicle. Like alignment, these are pretty inexpensive mods that can absolutely transform a car. Going into corners this thing felt level, planted and extremely confidence inspiring. This car has a front bar custom sized for the tires and shocks it’s running, which made steering and front end grip go from decent to magnificent. If a stock C6 Z06 and this modified C5 lined up against each other at an autocross my money would be on the prepped C5. It was really that good of a car, and so much of that comes down to this front sway bar. Testing is everything, or finding a tuner or shop that has already done a lot of cars set up like yours.
Borla stinger exhaust and X pipe
The LS is already known for power and grunt, but more is better, right? This exhaust combination drops more weight than an actress at the gym, while adding torque across the board. By balancing out exhaust pulses (more on this in future articles), the x pipe raises net output from the engine. It’s a subtle but noticeable change that allowed this car to stay in a single gear the entire course. Autocrosses are short and tight compared to race tracks, and every time you shift you lose time in a manual transmission car. The ability to have a whole course covered by 2nd gear, with virtually no flat spots in the powerband, was a big factor in being able to focus solely on hitting apexes, steering work, and early throttle application.
Final thoughts
In summary, these are great modifications to make to a base Corvette that results in real world gains. No fancy or expensive engine work, no super costly race tires, just proven parts that give you immediate results. How much does all of this cost? Dan told me he spent about $17,000 on the car and another $4,000 to $5,000 in parts, having done most of the labor himself. Just one more reason I love the C5!
For help with service and mods on your car, check out the how to section of CorvetteForum.com