f20kills

Anyone here have a 3mm installed and tracked heavily? Or any opinions on boosting a motor with 13:1 compression for the track.

I will go FI eventually and want to get opinions or peoples experiences. Even if it not a track car any info is good
Thanks!

Kenny_Stang

I've been tracking my car for over a year supercharged and on the stock head gasket, other than you have to ensure you have proper cooling (bigger radiator, better heat exchanger/intercooler, and oil cooler) it's performed flawlessly. With that being said, I'm a relative newbie, so I'm not pushing the car as hard as others might.

f20kills

Unfortunately my current compression is 13:1. I feel like it can be boosted at the ratio (e85) but Id like to lower it if I can without having to do too much.
Thicker head gasket seems like the easiest way for now.

DefSport

A thicker HG reduces quench area in the combustion chamber, which generally increases the likelihood of detonation. The lowered CR might be a net benefit, or it still might be impossible to run on track with FI.

The main issue on track is that even if your IATs stay constant, everything else heats up, and you get more knock. I've never seen a tune that had phantom knock on the dyno or the street not knock like hell on track if the driver is doing anything more than toodling around. You've generally got to back off a couple of degrees of timing and deal with the lower power.


Is your pump gas 91 or 93 octane? That makes a decent difference when you're pushing the limits of the fuel. But E85 is definitely the easy button here. It'll do 13:1 with safety if the setup isn't insane as far as power levels.

f20kills

I run 100 octane since I can buy it at the pump and at the track. We have 91 here in SoCal but I decided not to tune on that. I have no problem boosting 13:1 as long as it's possible. I just don't know how these things work for tuning. I'd run a SC at 12psi making probably 350 to 400.

f20kills

I should mention Id run e85 for track days....maybe use 100 if its possible on 13:1 compression.
Do you think 100 is possible with 13:1 on track?

Im not trying to push the limits on the motor and tune....just being able to boost it on track will make me happy lol

DefSport

E85 will do better than 100 unleaded for that. Can you run E85 100% of the time? If so, that'll work out.

f20kills

If its the safest way, I can make it happen. Just not easy lol. Id like to tune for 100 also but not run it on the track. I can get 110 easier than e85 too...I have that option as well. Whats your thoughts on 110 leaded?

Sounds like I can boost with 13:1 as long as I use the right fuel and good conservative tune.

Kenny_Stang

At the end of the day, the most important thing is going to be the tune. Regardless of what octane you are running, with the right tune you should be safe, but you may not make crazy power. With a track car you have to be more conservative with the tune, and not go for the highest possible #'s on the dyno. I asked my tuner to set the car up to be safe and to sacrifice power for longevity and reliability. That means pulling significant timing as the IAT's climb (and detonation becomes more of a concern). That being said I have ran the car in 90+ degree weather in Texas, on the track without issue on 93 octane. The IAT's were in the 150's, but coolant never topped 210, and oil was ~260. Another idea would be to run methanol injection, this would give you some additional buffer against detonation and also cool the intake charge significantly.

King Tut

If your current head gasket is fine I wouldn't swap a gasket just to run boost. A good tune and E85 should be no problem.