How much boost can a stock 3.2 motor take?

[d993]

I have a '87 911 which I turbocharged myself. I currently run 9 psi with a GT40R turbo.
The engine has stock internals, only mods are Mass Flow Sensor package, 944T injectors, and high flow fuel pump.
I can adjust timing, fuel, and control intake temperature.
I just want to know (under ideal conditions, assuming it has adequate fuel, timing control, and sufficient oil cooling and intercooling) how much power the 3.2 can take before the case comes apart or something breaks.
And please, I hope nobody says 350hp is the limit, since it produces considerably more than that now, (as a poor Z06 owner found out recently) and it's been running well for about 2 months (driven and street raced daily).
Thanks for any useable info.

[dickster]

considerably more than 350 - i believe. try a search one or two members are running high numbers.

arent the rod bolts the weak link?

anyways, please post pics and details of your setup, i'd love to hear more about it. how'd you do it? what did you do about fueling and ignition?

(thought i should get in before the synics )

cheers

[thrown_hammer]

When my engine was rebuilt they replaced the rod bolts with raceware and increased the diameter to I beleive 9mm. And please share the setup!

[magilla]

Juan Ruiz's is running 600+ and is still in one piece. I think you have a way to go before the case comes apart.

Do a search "juan ruiz". He has documented some of the stuff he has done to his 3.2.

Good luck.

[juan ruiz]

I just want to know (under ideal conditions, assuming it has adequate fuel, timing control, and sufficient oil cooling and intercooling) how much power the 3.2 can take before the case comes apart or something breaks.



1,000 hp no problem...........

[JeremyD]

Boy - that's better than coffee to wake me up in the morning... Yes, details - damn - and Juan - how's your project coming? I hear on Tamparacing every once in a while about some "porche" in S. Florida that's beating up on the supras down there... I figure that has to be you!

[juan ruiz]

Jeremy964

Thanks for asking, we doing ok, many things have change but I am just keeping a "Low Profile" as not many people share the passion the way we do.

I am redoing a "Few" things and I be experimenting with some "proto type" cylinder head work, I am sure that it will be a complete success just like the "Experimental turbo"

[emcon5]

Originally posted by d993
(driven and street raced daily).
Thanks for any useable info.

For daily street racing, 2 bar should be about right.

Originally posted by magilla
Juan Ruiz's is running 600+ and is still in one piece.

Juan isn't running 9.5:1 compression.

Tom

[Wil Ferch]

9 mm rod bolts ( size) is stock for 3.2....10mm was stock for 3.0.

Fuel / ignition / boost may be realiable for a certain set of atmospheric conditions, but may be too aggressive for hot days, high altitude, ....who knows what else. People doing this will get right on "the edge"...so be careful of ALL the parameters involved.


---Wil Ferch

[masraum]

Um, did you reduce the CR or replace the rings when you did this. Did you do anything with the valve train or rod bolts? Did you increase the rev limit? Did you go through the thing or just tack the turbo onto the outside of the motor.

A few people who went went a supercharger setup from Knoxville on a 3.2 have seen major blowby after several months of use.

[RickM]

Yes....you're limited by the rod bolts and by compression. Seems to me running at 9lbs is on the high end for stock compression.

I too would love to see details on your setup ....with pics if possible.

What did you do regarding the timing? New chip...from who?

Did you use a rising rate fuel regulator.....etc, etc, etc

Thanks.

[thrown_hammer]

Looking thru my stuff you are right. My rodbolts were upsized to 10mm raceware units during the rebuild. stock 3.2's have 9mm.
Also who are the people that have had probs with SOK supercharger on the 3.2? I have thought of going that route myself.

[Roamer]

Wil brings up the most important issues regarding adding boost to the na motor. The stock compression is a little high for boosted applications and can lead to detonation way before you get to the limits of the block. Moreover, intercooling will play an even greater role as you go over 7-9psi. You may also run into problems with excess heat affecting seals.

However, it does sound like you took the proper fueling route with the 951 injectors. You may want to consider upgrading the ignition system with an MSD unit to ensure you don't "blow out your candles" with too much boost.

You should also consider the ancilliary issues very seriously, namely oil cooling and transmission (clutch and gears) issues. I am assuming you have also upgraded the brakes and suspension to withstand the much higher velocities you will be seeing with over 350hp.

d993 Please provide some info on your home-made system, it sound well thought out and many of us may want to follow your lead.

[masraum]

Here's a thread with some info on supercharging and one of the people who experienced blowby after supercharging.

Supercharging a 3.2 - Questions

[Amac]

If your running stock compression, I would'nt go
over 11psi. You may want to try racing fuel, it will
help keep the detonation down.
Be carefull if you have adj. boost.
1 bar is about 15psi, 2 bar is 30psi.
I'm running 2 bar on a 800hp twin turbo, you could
never run that kind of boost on a high compression
engin.
Glade to see the"Junkies" are still around!!
Juan, on my last dyno run I was running out
of fuel at 7000rpm. Made 794/ 652 at the wheels.
I now have 96lb. injectors installed,
waiting for Dyno time.

[juan ruiz]

Amac

NICE , Install one of those "Real fuel Pumps" "Aeromotive" and you be good to go

Just in case you miss it

HP Junkies Project up date

d993

"We are just trying to keep your dream alive"

[anh911]

Hey Juan and Amac (don't mean to hijack) what kind of clutch do you have in those puppies?

[Amac]

I'm running a carbon fiber centerforce with a
alum. flywheel.

[Kemo]

Originally posted by juan ruiz
...but I am just keeping a "Low Profile" as not many people share the passion the way we do.

Juan,

I used to love reading you posts...I dont have the funds to pursue the HP like you die hards...but i love reading about it and dreaming! Feel free to post anytime about what you got cookin under the hood.

[JeremyD]

Originally posted by Kemo
Juan,

I used to love reading you posts...I dont have the funds to pursue the HP like you die hards...but i love reading about it and dreaming! Feel free to post anytime about what you got cookin under the hood.

+1