utkinpol

Hi,

could anybody explain in more or less complete details how M96 engine used in 997 cars differs from 3.6L M96 used in 996 cars and what exactly gets done to X51 variation of 996 M96 engine?

Thanks, Paul.

Flat6 Innovations

-Compression Ratio elevated by 1/2 point
-CNC ported intake and exhaust ports
-Altered camshaft profiles with both more lift and more duration
-Altered intake manifold plenum
-Altered scavenge oil system for cylinder heads.

A few other smaller details. Roughly good for 25 RWHP on my dynojet.
I take these to 3.8 liters, do more head work, alter cam timing and throw a few tricks to them and 350 RWHP is common.

utkinpol

Jake,
great info, do you know if x51 996 m96 camshafts are same/similar as stock 997 m96 or is 996 m96 non-X51 is exactly same internally as 997 m96?

essentially I am trying to understand if there is any reasonably cheap way to safely increase 997 m96 redline to 8K rpm and if X51 996 m96 'kit' or 'mod' is something that gets done for that. right now all I have is a softronic flash plus 200 cell cats, engine feels adequate but redline is a bit short. I totally understand it is not a GT1 block and will never be one, but just curious of what can be done to it to make it more 'race ready'.

Please PM me if this topic is too detailed for regular thread, I would be interested to hear what options are there for 997 m96 and how much approximately it may cost. my engine # is 696113xx.

Regards, Paul.

Ubermensch

What are you basing the belief that your redline is too short on?

-Shawn

fpb111

It's something his girlfriend said, not sure what though??

utkinpol

i do not treat any motor as some sort of a holy cow, all engines can be worked on and a lot of stuff can be altered. my engine goes off CPO in 2012 and I will have some fun with it after that for sure. some things can be done, some things cannot be done nor improved, it is all a matter of knowledge, desire and available parts/budget.

obviously there are not as many things you can do to a m96 motor as to gt3 motor, but i would prefer to keep it NA but get it balanced, make it able to rev higher than just to put a sc blower on top of it. again, it all depends of what is doable and what is not and for what we do have parts/kit available.
for now all I wanted to know was what specifically can be applied to 997 M96 engine.
on last dyno graph my flat max Hp section starts at 5970 and goes until 6830 or so. are there any known means to prolong that flat max output section higher into 7200-7400 area or alter the curve so max output power point would move from 6830 something into 7k+ something point?

Ubermensch

I just wanted to make sure you were aware that HP flattens out below your current redline. That suggests there's no particular reason to increase your redline since you'll be putting your motor under a lot more stress to make no more power. Your best bet is just to shift gears at that point to take advantage of gearing. If you had made some modification to generate more torque and extend the meaningful power band, then I would agree that increasing your redline might be useful.

-Shawn

utkinpol

what I have done so far was only basic 200 cell cats, plenum and softronic, it helped a bit to improve air flow and made up curve shape more linear at upper band so it pulls much more equally than stock but for some AX configurations i do run out of 2nd gear and upshifting eats up time, so, well, again, I am only investigating what options are out there.

like i said before - i do realize completely m96 is not a gt1 block and will never be one, still, if anybody went over some research to find out to what degree it can be pushed - it would be interesting enough to hear about.

most i heard so far were works on rods bolts, balancing camshaft, some other quirks but info about all that is pretty scarce and i do not have any certain feel of what real effort does any of that require. most folks seem just to throw in LWFW, put on same stuff I did and run it till it blows, then put on next one. may be it an only way it should be done, i do not know but i guess it does not hurt to discuss it.