I have a track use only caged 2005 AP2 with a stock no engine mods with with about 15,000 miles on it. Last summer I installed a Password JDM intake and an AEM2 ECU in an effort to find more speed. Still do not have the speed I would like and I am looking a FI. What is the S2K form's general consensus on FI? Turbo or Blower? Build from scratch or buy a kit? My tuner is recommending turbo with some custom made components.

 

Drive line needs to be enhanced too as well as the fuel system.

My limited experience with the two systems indicates a supercharger provides smoother power increases in places like corners rather than a surge of power when the turbo finally decides to spool up. Other than top speed on straights mid-range power is most important. Either method can be handled with experience. I'd think the experience of local drivers at your track(s) is key; they're your measurement point. If you trust your tuner his recommendation should carry some weight assuming he has success with both systems. If he's a turbo-only guy it's like asking a Chevy dealer about Fords.

-- Chuck

 

Until very recently, if you wanted torque you had to go turbo. There are now two PD superchargers. I'd explore those before considering tracking an aftermarket turbo car. One uses a TVS unit, the other a whipple. They have differing degrees of "polish" but both will easily get you 400whp on pump gas. On race/E85 I wouldn't be surprised if you got close to 500 whp. However at that power level with all that torque, I'd research the longevity of your drive line components. Good luck on your project.

 

I would avoid the Turbo for several reasons, partially because of boost lag unpredictability causing more effort/focus from the driver running the car on the edge at all times successfully to be fast, and added heat management/reliability and cost. Centrifugal Supercharging is better in all of these regards as long as you are good with staying at a reasonable bump in power in the 400-450whp arena. The trq output and delivery will also be kinder on the oem components if this is important to you. The positive displacement options mentioned will get around some of the short comings of turbo drive-ability and heat management, but overall wear and tear on drivetrain parts will be about the same. Also remains to be seen really how these two options which are still in their infancy of beta production will do in the rigors of track work. Unless your willing to be a bit of a Ginny pig, I wouldn't see these as viable options for a couple years yet until we get to see some kits out there working for a while.

Reliability to me is the number one aspect, you have nothing but aggravation and despair if you invest in a track day to not know if the car is going to hold together long enough to make it through a few sessions or the whole day. SOS supercharger is what I would go with today if I was looking for a reliable FI option. Out of the box KW is not reliable. Turbo is not reliable enough, to many variables and things to go wrong along with the added drivetrain abuse and then the drive ability issue with boost lag/power delivery as mentioned.

That's my view on FI for the track. Its going to come down to how much expendable money you have to throw at random problems and wasted track days, and your general threshold for dealing with these issues. Mine is pretty low. Id rather focus more on utilizing my driving to not have to cover up mistakes then having max trq out of a corner. A centrifugal sc retains all the character you are used to of the NA power delivery, but its like adding 2-3 times the displacement depending on how much boost you throw at it, its really ideal for track work in my book. Some added mid range trq for the improved motivation out of the turns and a lot of top end hp to get you down the straightaways.

 

Interesting perspective guys, thank you.

 

im super in favor of turbo, IF, you have a good tuner. a sos s/c or rotrex kit is "easy" and the power is typically more than enough for most. the power delivery is very linear and fairly easy to modulate. that said both turbo tech and more importantly tuning tech is so much more advanced now than years past. sure if you tune for the basics and a turbo does take alot of "driving". but with advanced boost control techniques like boost by tps, speed and gear you can have the best of both worlds. i never have "boost lag" on track. i think its a slight misconception from those that have never ran turbos. the problem is quite the opposite actually and even in part throttle sweeper im able to reach max boost pressures which is technically more power than i want so it becomes a bit of a peddle game. that said you can run boost by tps which will limit part throttle boost pressures and ramp higher boost levels in as more throttle is applied. your can also ramp boost in with speed where in 4th/5th you have more grip as speed increases as well as setting higher boost thresholds in the upper gears where your going to be running down the straits. again this approch takes a far more indepth form of tuning but overall will give you a much broader powerband, more torque and just a much more efficient setup. all heat related issues are easily addressed, i know i have done 4-5 hot laps at 75% (shakedowns) with 105* ambient temps and never saw over 200* ect's. this past fall i went for my first real pushing 10/10ths laps and was doing 2 hot laps(all the re71s are good for) ambient temps in the 60s and never saw over 195ect's. i dont feel there is much added drivetrain abuse when power is properly ramped in aside from the fact you can run considerable more power than the average 350-400whp s/c. that said i still tuned for around 400whp on track, its alot of power to play with out there. as i get more comfortable i may ramp in more in the upper gears for more strait line speeds if needed. for now the power is plenty

edit: one note to add, i do think s/c is the easy and more strait forward option for the average guy. its typically more than enough for most people. but a turbo kit can be made to be a better option when properly designed and setup but takes a far more in depth skill set.

 

I'm a newb when it comes to pretty much everything turbo. What kind of hardware is necessary to run/tune that granularly?

Can it be done via FlashPro? Does it require full standalone? Are there extra sensors/hardware necessary to tune to that potential?

 

smaller wastegate spring (4psi or similar, remember you can always add boost but you cannot go lower than wastegate spring pressure) and a 4 port boost controller. im not sure on what boost control functions the flash pro incorporates. i know aem v1/2, haltechs. etc most all ecu options have boost by tps, speed and gear.

 

I personally decided to go with a borg warner EFR turbo charger. I went with the 7163 which should make over 500whp with little to no boost lag because 1, its an efr and 2 its only a 57mm turbo.