TURBO FOR 2.8L?

[GARY TUCKER]

I have just finished a total performance rebuild of my 1988 Fiero gt 2.8L...I used forged pistons with a compression ratio of 9.5:1 and am thinking of getting a turbo that is put together by a guy in NJ named Dennis Laguria...anybody know if this compression ratio is too high for a turbo?

[geoffinbc]

It will be ok as long as the boost stays in check. Keep the air charge as cool as possible with a nice intercooler and run good gas and you will be alright.

Remember that companies sell supercharger kits for new vehicles where compression is already in the 10's

[Rhedalert]

Re: TURBO FOR 2.8L?

I have just finished a total performance rebuild of my 1988 Fiero gt 2.8L...I used forged pistons with a compression ratio of 9.5:1 and am thinking of getting a turbo that is put together by a guy in NJ named Dennis Laguria...anybody know if this compression ratio is too high for a turbo?

Go for it....what kinda cam is in it?

[SappySE107]

Damn it, I know that name (dennis)....but I dont know why right now.

The compression ratio is fine, but it depends on some other factors such as quench. If Mick is around he could explain it better than I can (or someone else who knows quench, piston to head clearance...).

[z24turbo93]

haha.......9.5 compression might be a little too high. If you are going to run turbo it would have to be at like 3-4 psi. If you want higher you will have to go with race gas. But go for it

[SappySE107]

Odd, there is someone around here with 9.6:1 running 12 PSI on pump gas. Where are you getting your information?

[z24turbo93]

i got most info from v6z24.com, some from raven, some from curtis walker..............i know he isn't wrong maybe they left out some details. But frank with the 3.8 turbo has to run race gas if he wants lots of boost. Don't want to say they don't know there stuff because i know they do..........and where is this guy running 12 psi with that much compression on pump gas? just wondering

[z24turbo93]

he sappy i know the website that makes the turbo for the 3.8 camaro......http://www.forcefedfab.com/, i don't know if you have that info or not i just seen you were looking for it under the forced induction section of the website.

[Rhedalert]

I thought the figure to look at when using a turbo is the actual compression, not the ratio? I need mild enlightenment

[SappySE107]

Yes, cam timing is going to effect this a lot. Mick (mechanic) has the 3100 fiero running 12 PSI. That is why I wanted him to explain the quench, because the Gen 3 engines despite having higher compression are better with boost.

I um...never look for anything having to do with 3.8 liter engines. They are iron heads, which its different for boost and NA.

Anyway, back to compression, I have no idea what the dynamic compression is between roller and flat tappet designs. Curtis is using iron heads and low compression. Frank...3.8, doesn't matter much to me from any standpoint other than it has a turbo. Computer tuning is also going to dictate the boost. Properly tuned you can throw more air into the chamber without knock. Knock is really bad with boost.

[Guest]

z24turbo93, Please don't put words in my mouth, since I will be one of the first to say that high static compresion when tuned right can work very well with boost, the key words here are "tuned right"

[z24turbo93]

yeah curtis said if it was timed right it would handle it. So it shows how much i know on some of this.

[DarkKnight]

AFAIK, you can run high boost on a ~9.0CR (on pump gas) as long as you retard the timing, run rich, and use one hell of an intercooler! Still, it might end up being cheaper in gas to use high octane, as running rich will end up killing fuel economy. (and cause quick carbon buildup)

[El-Stupido]

i thought that guy with the 12psi fiero used tgp pistons and had a 9:1cr. but its been a awile for me.

the 2.8 turbo ive got waiting in the wind is going to have about 8.9:1 but the "60 trim" t3 turbo's will only push about 6 psi (about 7 for the "super 60"). the turbo is a little out of its efficency range so a real good intercooler will be needed.

dont the big timers use propane injection to boost the octane of the fuel and cool the charge?

[z24turbo93]

what you talking about??? only 6 psi from a t3 what the hell is wrong with it...........or is wrong with your set up?