Hey Steve finally came over to do some research haha


What makes the 997 better at putting more power down at the front if its the same pieces as the 996?

 

When I had my 996TT, It was pushing 650BHP and the car had significant suspension work done to it. I converted it to RWD as I did the GT2 front bumper/aero conversion. The difference transformed the car. The steering was so much lighter, the power delivery was amazing, and the car just felt more nimble.

The whole time I had the car in AWD, it never felt "nimble" and steered heavy. It was fast, sure, and I could dial out understeer, but the "feel" was night and day.

Mike

 

Craig (his 6sp name also) found this out years ago.

The axles are a problem around 900hp, but I'm pretty sure that the system never crapped out. He had a upgraded 9ff tip trans though...

try searching for posts by "craig"

 

Im AWD with stock axles.

 

997's unit has a clutch in it the is controlled electronically. Really puts power down not a guess.

 

I agree that the car is much faster with it off on the track, if you forget to turn it off, you are reminded real quick that something is wrong
If mine was my track weapon all the time, I would convert it to RWD for sure but for a daily driver and the few times I've been caught in the snow it seems to work fairly well, I've have a UMW stage 2A never had it dyno'd, so I don't know HP

 

I wonder how much power you really put to the front. I cut my viscus coupling open. it was like 25-30 plates, like motorcycle discs but very thin. there was no friction material on them. there was no pre loading springs or anything that added pressure to the stack. I was told that the oil is the key, as it heats up it gets thicker that gives more resistance on the discs and makes it harder for them to slip. Its a sealed unit and when I cut it open on my lathe boy did that oil stink!!!

 

PSM is never fully off unless you unplug the pre charge pump.

 

Steve, Adding camber greatly reduces the amount of useful tire that is in contact with the ground going forward. It how ever does do wonders for turning grip. So guys who run a GT2 alignment with rear wheel drive and no lsd on the track or aggressive street driving, not straight line stuff will say the car just blows the tires.

 

I have only had my 996tt for a few months, but have had it out on the track 6 times. It is the first awd track car I've had, and I bought it as a daily driver/backup track car. I was surprised and impressed with the turn-in and cornering on what I expected to be a heavy feeling car. Others who are experienced with 996tt's and have driven it attribute this to the suspension setup, which was done by GMG. I am used to much lighter cars on the track, but I like the feel of the awd system, and it doesn't feel heavy to me. There are a few corners that it really helps pull through, and this car keeps pace with much lighter cars through the turns. I can and do throttle steer in most situations much like my rwd cars.

I may look into it at some point if I really want to lighten the car, but for now I really like the awd system on track. BTW, I used the PSM for one session on track, and never again! I thought I would have swapped ends by now without it, but even at an aggressive pace this car is very forgiving.

I have not driven newer awd systems on track, so my perspective is limited. But my impression so far is that the 996 awd system works very well with a good suspension setup.

I am having bigger Tial turbos installed, with supporting mods, with hopes of ~600 whp. I plan on tracking it this way for a while.

 

I run 600whp AWD... 18' Toyo R888's... I chirp 2nd & 3rd gear, I am never at a loss for traction outside 1st gear.

 

Mike, I have to admit that the steering feel improvement is something that I would really like to try. As I don't have ready access to a GT2 I think the only way I'm going to get to experience it is if I convert my own car to RWD.

Thanks for more good information ttpopo...appreciate it.

Jag,

Having seen your car in person and being local to you, I should pick your brain a lot more about this point. Clearly your car has enough power to overwhelm the stock system (if any can) so I'm really keen to hear how your traction is when you're really laying into the throttle with big boost. Your input would be very worthwhile since I'm not planning to get anywhere near the level of power you are making.

Thanks Tim...that makes a lot of sense. So, effectively you're saying that even when I lower the car it would be smart to stick to a 996TT alignment, rather than going to the more aggressive GT2 alignment (for straight line traction, that is). Right?

Great feedback, thank you very much for taking the time to reply.

LiNks, I'm most likely to build my car to about the power level you're at, so definitely appreciate this information. I will probably end up in the low 600 whp plan if I can follow my current mod ambitions. Thanks again!

 

Steve

Anytime. Call me at 253 332 4879.

Jag

 

I run RWD with a Wavetrac diff on a k16 billet car @ 1.4 bar with EBC 4.5" intercoolers, fueling mods and Aquamist HSF4 system and a bunch of other suspension and engine mods around 580-600WHP . I went to RWD drive out of a whim to try it out and will never go back. The cars steering is light and with the LSD and GT2 slave mods the car is just a blast to drive (predictable and a proper 911) . I came from a 964 Turbo and the car now just feels like a 911 should to me.

 

my research found this. those that are long time porsche owners and road race want rwd so they have the feel and expectations of the porsches they owned before with the power of todays cars. drag racers want rwd for weight savings and ability to run drag radials in the size they want without fear of trashing the front diff.
this is my first awd car. when i ran the twistys it made me "feel" like a better driver than i really was.( im by no means any kind of road racer) i went rwd for a simple silly reason. it was FREE! i wanted to try modding this car on my own and with the diy and the help of the forum i tackled the job. now the car feels lighter in front, more nimble when i turn in and i can do a small burnout at the track to clean the tires off.
it was a worthwile mod for me and of course i can go back with a couple hrs work