I have done it, will be tracking the car in two weeks so I'll have better opinion then. But for now, it seems ok, I dont see what all the fuss is about as of yet.

 

Reporting back about a year after the mod....the car runs great with no kind of PSM or ABS lights going off. The car gets slightly higher gas mileage....5-1mpg. This is by far one of the best mods I've done to the car.

 

Bump for the new members...

 

I'm ignoring blingking as he has absolutly no idea what he is talking about. He needs to read up on definition of "threshold breaking." When ABS kicks in, you already passed it. That's why it's call "Anti Lock".

Is there any news from heavychevy? How was the track feel with the front disengaged? Did you remove everything or just the center drive shaft? Did you do it yourself? Any shimy? Does your front tire wears even less? Is anyone on PS2 Cup and did the conversion?

 

I only removed the shaft, but watched s it was done, isnt hard to do at all and I helped put it back on when I changed back to AWD (so I guess that gives you a clue as to how I feel about it).

Positives:

Turn in much better

Negatives

"MY" car was slower in a straight line by a good amount.
The car is less stable on high speed sweepers


I lost a good bit of straight line speed from my AWD by just removing the shaft, I am the only one who reports this though, but not the only one who doesnt like the car as RWD. The understeer in the car is still present but greatly reduced. The turn in/push issue can be fixed by adding a rear sway bar which I have done.

It's not a big deal IMO, still not a GT2, you'll have to change motor mounts, get LSD, and lose lots of weight to get to that area. This car is not meant for RWD for a couple of reasons.

#1 The steering is dull and meant for luxury, a true driver needs feedback or else having RWD especially with more power is down right dangerous. The GT2 has a much better drivers feel and people still consider it a death trap in the wrong hands.

#2 Because of reason #1 you cant turn the PSM off while trying to drive on the road course especially on non communicative r-compound tires (unless you drive slow, I dont) If you have driven a road course and push your car you would know that the PSM comes on anyways, and having it on is a hinderance if you like to 4 wheel drift and use slip angles and such to your advantage.

So IMO if you are going to street or drag race, put slicks on the car etc, by all means do it (the whole conversion), but for anything else the car was still designed as AWD and you would have to change way too much to get the real feel you need.

Here are my lap times by tire and drive train setup.

March 07' 138.8 AWD, PZero corsa bald, hot sunny
May 07' 136.6 RWD Hoosier R3S03 (brand new, first use) , hot sunny
July 07' 137.9 AWD Hoosier R3S03 (on last leg 6th track day, 17th-22nd heat cycles), Wet track

 

I recently performed this mod. I removed the drive shaft and the front axles but not the diff. yet. So far the steering feels great. Much lighter, more direct, etc... I also added new Eibach sways at the same time as well as a Tequipment bar so a lot was changed simultaneously but the car overall feels great handling wise. Less roll and apparently less front end push.

My issue is with the PSM coming on A LOT now... This is likely due to the fact that I have a Stage 4+ so when the power hits, it reigns me in. I'll be taking the car to an autocross hopefully soon where I can finally play with it a little harder and see how it feels when really pushed... I'll report back then. Also, I have not done any custom alignment for this setup yet so that may contribute negatively as well...

 

If a AWD sends 5% to the fronts, doesn't a converted AWD still think it's sending 5% HP to the fronts (and thus bleeds off 5% of the total)?

 

There is no torque split in the trans. It's just a straight axle front and rear. The Viscous coupling in the front diff takes 5~40% of the torque as the liquid change viscosity when input shaft speed up more than the output (front diff in our case) and put it down to the wheel. Porsche designed it for the front to just be there to help out. Take all that out, there is nothing to take the torque just a spinning shaft.

 

I had a Gaurd chromoly LSD installed several months ago along with the 24mm H&R rear sway bar. It reduced the understeer considerably.
I have yet to have the PSM kick in since the LSD installation.
Before LSD, PSM kicked 2-3 times or more per outing.
(running PSS9, F&R carbon fiber strut braces and 315/25/19 PS2's)

I am strongly considering the RWD conversion with upgraded front sway
bar and GT3 straight links. Open for Pro's, Con's and opinions.

 

So you're runnning LSD with AWD?

 

Yes, now for 1000+ miles. I have it set on the 40/60 setting, it has an alternate 50/80 setting for track use or 13" slicks.
I was upgrading the clutch to a 4100lb Sachs w/ceramic disc and
it was only 3hrs more labor + parts. This is when I also installed the 24mm
H&R rear sway bar and the Agency Power sway bar links.
With the LSD installed I don't think I actually need the AWD.

What is your opinion on the larger front sway bar with straight adjustible
GT3 end links?

 

I only have the rear, dont have any oversteer problems. I would get one if you go RWD though.

 

I'm glad I skipped to the back of this thread and read Heavy Chevy's post... Good to get the perspective of someone tracking their car the way I use mine...

I'll be staying AWD!
Mike

 

I'd like to see some RWD guys that actually like to take turns on the track at the same time. Most of the ones here are big HP straight line only guys. But this car is difficult to drive in RWD, especially at our power levels. I'm sure the LSD helps with the constant PSM you'll get without it, but the steering is way too soft, if you lose it, you wont know until it's too late. And you still dont completely eliminate the understeer because with removing the front drivtrain you take away something the Turbo needs and that's weight at the front of the car when turning.


BTW did anyone see the Turbo racing SPEED GT @ mid ohio, there was a quick glimpse of it. Dont know if it was 996 or 997 though.

 

Guys, as some of you know. I had a 996 Turbo for 2 years, hated the AWD and PSM even though when I bought it I thought I would like it, it was a boyhood dream of mine to own one.

So I took a bath and sold it and got a GT2.

Problem is, this rear seat business is going to be a problem for me sooner rathre than later. When we have kids, the GT2 is going to become worthless, because I can't put a baby seat in the back.

I konw it can be done, but to risk possible insurance coverage problems on my family is just selfish.

So, I have looked into the possibility of converting a 996 Turbo to GT2.

I can live with the weight and the thicker carpets and what not, but what I can't live with is PSM.

So, here is what I think is needed:

1. GT2 harness.

2. GT2 DME (which means GT2 turbos)

3. GT2 front carrier.

4. removal of front transfer case and half shafts

Please add other required parts.

Maybe, just maybe it can be doable...

Plus the Turbo insurnace is light years cheaper than the GT2. And yes, I am speaking from experience.