Jim Nowak

Dyno the car and make it ready to drive with the rest of the exhaust would be mimimums. Paint the car, dye the interior, install new carpeting, get some good looking aftermarket wheels, and a GTS fin to make the car more attractive. As is, it is just too unattractive to appeal to a wide audience. A run or two at a dragstrip with some actual times would also be a bonus.

I look forward to your S4 project and wish you the best of luck in selling this car.

tammons

Twin custom SVO T3's on the first two setups. I never could figure out how to stuff a t3/t4 in there. Too tight and besides a bored out pair of custom T3's will make 600 hp. Thinking back I really wanted the same setup, svo trubine section and a step or two up on the compressor side with a clipped turbine wheel but with ball bearing turbos, but that starts getting expensive. Probably a water to air IC too, but now i like life simpler.

My last car I decided to built as a reliable street car and did a euro style on center single T04. Stock those can handle about 450 hp but can be built up to around 550 or maybe 600 with a lot of work. I put about 2 years of daily driving on that setup. On the last one I was just burned out on the whole TT 928 setup, especially around the steering shaft.

The 950 hp guys never would tell me what they were using, but they did say custom twins, and I assumed that was either a T3/4 or a K26,7/8 or whatever hybred. Those guys got huge money for building custm turbo cars

If I ever do another 928 it will be a S4, with throttle body FI and a tec III.
Not sure about the turbo, but after going through the whole twin thing I think I would do a big single custom ball bearing turbo mounted on the passenger side towards the back. Similar to that rayjay setup. That setup actually looks fairly simple. Twins are more exotic though and should spool a little faster.

Are you going to use the same style manifolds.

Herr-Kuhn

Yes...simple manifolds because of space. I think there is room for a T3/T4...but you have to give and take on which ones you use.

tammons

You might want to look at a pair of buick GN turbos. I think those have the bigger t3 exhast housing with a t4 compressor side. Not positive about that though.

DFWX

What did this twin turbo 928 sell for?

DFWX

Turbos with long piping are not particularly good quarter mile cars due to turbo lag. The turbo 944 guys will confirm this. However, they are extremely fast road cars.

FlyingDog

It sold a week or two ago on ebay, but I didn't check the price.

sublimate

IIRC, it was somewhere around $9K.

AFARR

$8,800.

I cried when I saw that...

If I had known how cheap it was going to be.....(I know I can get along on only one kidney...)

Drewster67

Wasnt this car called Gold Member?.

Id Say a Steal at 8,8K - Bump the PSI and make it a track car - after you gut it of course!

m21sniper

"Turbos with long piping are not particularly good quarter mile cars due to turbo lag. The turbo 944 guys will confirm this. However, they are extremely fast road cars."

They are when they're automatics with a sufficient stall speed.

The 928 has a pretty high stall, about 2300rpm....which is plenty to build boost while staged.

Jim bailey - 928 International

Herr-kuhn posted on the Turbo thread....."Two K-24s and 8-9 psig yielded 265 RWHP and 355 ft-lbs torque through 3-spd A/T 4.5 liter on a 100F day...literally, the dyno room was 98.5F and we made 3-4 pulls with minimal air flow across the charge cooler. No detonation or pinging with back to back pulls. Those K-24 turbos are quite small (picked to help spool times because of the A/T). ....." My old very brown 1980 4.5 dynoed at 194.5 HP torque 225 ft lbs stock. So a significant increase especially in torque.

James-man

That torque number is very impressive. Even by S4 standards.

I would guess that his HP curve is flatter and starts higher than my 32 valve. "Area under the curve" probably looks very good.

I believe that Goldmember (automatic) against my 5speed '86.5 (271-272 RWHP) could clean my clock on both 0-60 and 0-100 runs.

Someone got quite a bit of car for the money.

tammons

That entire turbo setup should sell for as much as the car. It was very very cheap.

I called a turbo builder about 8 years ago about building a setup for me. The estimate was 8G min and up for a single, and that was a starting price. That was before i decided to tackle it myself. You could not even imagine how much time he put into building that setup. I know. Believe me its in the hundreds of hours.

Jim Nowak

With such a great amount of torque and relatively low RWHP, this would be indicitive of a power curve that peaks very early and drops off past 5252 very quickly. Picture the slope of a kids slide at a playground and that's what his hp and tq look after 5252 rpm. HP = tq * rpm/5252. Had his torque stayed higher past 5252 rpm his RWHP would have been much greater. In other words, the low and midrange is good but up top it dies quickly.

Picture something like this but less tq and hp: