sydneyACE

So I wanna go FI on my C5. I do HPDE's about twice a year, and the car is my daily driver. I would like to know what everyone's opinion is here. Which FI option do you guys think is best suited for track use (Pos. Disp. SC, Centr. SC, or Twin Turbo). I already have an idea, but I would like to see what the road racers out there think. I'm definately leaning towards Centr. SC because I think it's characteristics would be best suited to track days. I think lag would be an issue with TT, and the torque of a PD SC will probably cause traction issues. What type of FI set-ups are you guys running? What are the pros and cons? I know most people say NA is best on the track, but I think FI will be better for me because of the car's uses.
Thanks in advance!

Solofast

Centrifugal superchargers really only work at top end, and in a RR car you want power coming off of corners to reduce lap times. While the lag has to be considered, midrange torque is more important than high end power....

Forced induction for a track car is really not a very good idea unless you mod the entire engine to handle the additional heat generated by the supercharger. If you just hang on a SC, unless you keep the boost very low, realibility will suffer. Better to go with more displacement than a SC system from a reliability standpoint.

C6-CYa

I track my Maggie at HST events and the only problem I ever had was throwing the belt. Put on a high strength tensioner and haven't had a problem since. The Maggie has plenty of torque down low to rocket out of corners. She gets hot but has never overheated in 20 minute sessions. Stock clutch has lasted about 13K miles.

0corvette pilot

when my C6 had a vortech supercharger on it, it would overheat in 10-15 minutes with air temps above 80. Had to remove the supercharger to keep tracking the car.

I think a liquid cooled maggie might work, but anything with a big intercooler blocking the radiator is going to kill you.

0EPP

Check out what we did on this C5 to make it work.
http://www.exoticperformanceplus.com...Car.php?car=54 Bob

BrianCunningham

Looks like my build only it's a C5 instead of a C4

sydneyACE

I've looked through that build before. Great work! I know the heat issues can be dealt with, but I'm on a super budget. I plan on saving up some money for a SC kit, put it on, and DRIVE. I'll probably keep the tune and boost levels very conservative as I can't afford a forged bottom end for quite some time. Just kinda courious from a "power delivery" standpoint which options usually work the best. I know NA is the prefered option for RR, but I don't think I'll be as happy with that on the street (gas mileage, drivability). I'm not trying to make it into a race car, I just want to be able to take it from street to track without having issues (besides changing brakes).

AlwaysInBoost

if you're only planning on tracking the car a couple of times you will have no problem with a centri SC. How hard you drive the car will effect how hot things get for. you can keep things cooler by installing an external oil cooler and dewitts blower rad. I have those two mods on my procharged Z06 and haven't had a single over heating issue in the 7 events I've done this year. Two weekends ago @ Thunderbolt I was seeing oil temps in the low 220 range and coolant temps around 210.

sydneyACE

Thanks, that's the kind of input I'm fishing for! Which kit were you using? (intercooler style) I wasn't really leaning towards a PD, a hood equals another $1k... but if that will work better for me then I'm not gonna overlook it.

My car has extra short gearing (3.90's in the rear end w/ a Z06 trannie), so it's not hard to keep it in the high RPM range.

Anymore track experience with a SC?

sydneyACE

Thanks! I do run it really hard. I was just looking at some of your youtube videos actually. I will definately look into a radiator. Which SC kit are you using? (intercooler style) I've been leaning towards the A&A kit.

kenw

I have a 06/A6 with the APS Twin-Turbos. The engine is stock except for the APS kit plus Com. Cam lifters and springs. Dynotech (DTE Powertrain) did the install and Phil set it up with 7lbs boost. (507hp/512trq) The only issue I have had is engine oil temps, after about 20 minutes its running 280 so I usually back off the last few laps. The power has not been an issue since the turbo's spool in around 2200rpms and the torque curve is very flat. Even though I have ZO6 rubber I do have tractions issues and have to be careful, mainly on the straights.

I also have a 2000 C5 that is set up for the track but the power of the twins is hard to pass up.

Most will say and I agree FI is not well suited overall for excessive track use.

Good luck with whatever you chose.

brkntrxn

Personal experience:

When I started open tracking several years ago, I had a 554rwhp Mustang Cobra with an intercooled ProCharger (centri). Having the power was great, but it was actually a handicap when trying to learn the basics of road course driving. After battling heating issues for several years, steadily decreasing the power levels, and blowing two engines in 12 months, I finally succumbed and sold the blower and went naturally aspirated with the last engine. Best decision I ever made for that car. I was suddenly able to run full sessions, not work on the car between sessions, and enjoy my weekends.

With that said, the 03 Z06 I now use as my track car will never get forced induction. I don't ever want that headache and money pit again. Sure I miss the power, but the higher maintenance and cost is just not worth it to me.

If you are only going to do two events a year, you may be fine. But once you start driving the car hard, you may start encountering heat issues.

My .02

SweetSavannah

My FI experience was in a 427TT, 710RWHP, 790RWTQ.

Quick answer: NO!!

Here's why:

1. Heat. Unless you can find a way to extract it, you'll burn things you didn't think possible.

2. Drive train components: They'll fail (clutch, diff, tranny) once you get north of about 600 RWHP; the higher you go, the quicker they'll fail. You'll also need every cooler known to man.

3. Driveability: You'll need to retrain your right foot exiting corners, especially in a TT car. Once you lose traction, the turbo(s) will spool and you'll snap faster than an alcoholic at a liquor convention.

4. Lap times: I'm 1-2 seconds faster at LRP in my 550 RWHP NA Z06 than I was in the TT car.

Of course, there's nothing like that W H O O S H! when you're going straight, but, for me, the trade-offs weren't worth it.

sydneyACE

I've started to consider a Pos. Disp. more now after doing more research... It seems they have better reliability than Centris. Plus the use of the Air/Water intercooler could be beneficial because it could be mounted in a way which doesn't obstruct the radiator. I dunno, I keep going back and forth on this issue.... Help!! but seriously, keep the opinions coming especially from those that have been there. What did you run? What were the problems associated with your set-up? How did you cure these problems?
Thanks to all who have povided input!

sydneyACE

bump

mdk

the next car I build wont be forced induction. I love the power, but the heat from forced induction is a battle. I built the car as a street car, forged the motor with lower compression, upgraded cooling, dry sump, coilovers, and adj sways. I went to my first track event last year and was hooked ever since, save your money for track mods, your going to need it.

AlwaysInBoost

I'm running an F1 procharger w/8-rib setup, making 700whp @ ~14.5psi on striaght 93oct. I was using the standard A&A single FMIC, but recently upgraded to their ram-air intercooler.

urslooow

had a sc'd c5 that I liked to put on road course. I would advise against it. do a cam if your main fun would be roadcourse. The heat build up is huge, even with a be cool radiator, oil cooler, trans cooler, still had issues in Fl summer/ late spring. also unless you address it the belt can slip off. this is not a super budget option. most sessions are 30 min and your car won't last as you drive better.

sydneyACE

Was it just me, or did the forum go down for a while? I was having withdrawals at work without it. LOL
So, I guess I wasn't clear enough in my original post. This is primarily a street car, I only do HPDEs twice a year, I'm planning on supercharging it regardless. I just wanted to know which FI option would be best suited for occasional track use. I've narrowed it down to Centri. or PD, and thanks to contributions from Alwaysinboost and others, I've seen that the heat can be dealt with (with proper equipment). So, would the low-end of a PD be better for the track, or the linear progression of a Centri? Does this just boil down to preference? Could the IATs of a PD be significantly reduced by using multiple heat-exchangers? Or perhaps by using ice in the reserviour during sesions?
Thanks again for all your input!
As I stated earlier, I know NA is best for the track, but this is not the car's primary use. I'm not trying to be bull-headed, I've just been planning on going FI for a long time. I think it's a great way to get power for the street.

sydneyACE

Bumpidy, Bump, Bump