m21sniper

Part of what you'd need to do to get the car to run right at high boost with twin turbos would get you a long way toward achieving that 500 N/A HP to begin with.

Namely, a tremendously free breathing intake(including heads and cams) and exhaust system.

I have no idea where one would fit two TA-44s sized turbos under the hood though, they're pretty big units(probably about twice the size of K-27s). A rear mount -90 trim compressor turbo unit would get it done though. -90 trim turbos are friggin' huge though(similar in size to a bus or semi tractor trailer turbo unit), so even then it'd probably be a tight fit.

Someone with way too much money for their own good needs to try to hit the 1000hp mark.

Tony

AS Marc and Normy said, its TQ. Perhaps the question should be "Max pratical TQ through street tires"

Dont worry Andrew, if any thing you will go through a clutch faster than normal and thats it IMHO. Ive seen you drive a 5spd

300-400ftlbs of rwTQhooking up at 2000rpm with drag radials is gonna stress stuff, no doubt about it. As long as the tires give way, as they most likely will using street tires, the shearing ,twisting and stress wont be nearly as pronounced on the internals....axle shafts... etc as it would if if the car were to really hook up..

Youre getting a "boostard" huh??

Jessa

What fails first in the 5-speed?

AO

OUCH! You cut me deep, Tony!

I'll know 100% on Saturday. You still flying? If not, feel like coming out to SanDiego? Should be fun.

tammons

On an Engine dyno i dont think it would be a big deal. Build the engine right and bolt on the right turbos, and use the right engine management system and thats it. These guys down here were close, although a competative shop said that they tended to exadurate their numbers somtimes.

Exaduration or not, just the fact that they broke everything in the drivetrain multiple times with no final trans solution tells me its going to take a custom drivetrain from the clutch back to handle that sort of power. The drivetrain alone would probably cost more than a decent S4.

Yes more money than sense, but there is a lot of that down here too.

One fellow shipped a brand new 993 turbo to a porsche turbo builder shop straight from the dealer to install a mega expensive setup mostly for bragging rights. That shops top of the line 930 engine was in the mid 5 figures with a lot of exotic materials.

hacker-pschorr

A friend of mine is very interested in having this done. Does anyone know who to contact about these parts, or who does the rebuild?

IcemanG17

Hacker
Steve Pappin from the LA area had this transmission, but he recently sold the car (not sure)...he still posts to the list under pappy??? I belive it was quite expensive....about $7K, but almost indestructible! Maybe greg brown knows more about it?
Brian

Gnarly 928

I've blown a few 5-sps with around 450 rwhp and similar torque numbers, but that was while racing. I also ran a full seaon without breaking any gears after I cryogenically treated the internals of my latest tranny build. Marc T. says Cryo is B.S., but so far it's worked for this tranny. (could very well be luck or coincidence) I think the boosted cars last because they aren't driven at "full tilt Boogie" for sustained periods. Even George Sunnen, out at the Gamblers Run or Silver State, he probably only hits full throttle for perhaps 5-10 minutes during one of his runs of 1/2 an hour(100 miles at speed) The street driven autos? They are probably lined-up just perfectly for a "show of speed" then given the gas for a few seconds at most, in a straight ahead direction, usually..
There are very few gearboxes that will reliably live with over 400lb/ft of torque, especially if used in a car with lots of traction like you'll have on competition tires with a big footprint. I looked into a sequential six speed from a famous european racing transmission maker, but they only make one capable of handling the torque numbers I produce, and it was near $50k. I also looked into having gears made by Paul Guard, the 911 gear guru. He wanted $18k to make some gears for my tranny. When someone actually runs an auto "booster" car at the track successfully for a season or two, I will believe the Urban Myth that an auto is stronger than a 5 speed. For now, I'd say if you want an unbreakable tranny, you maybe can get one in England for just $50K, and maybe in just about one year's lead time...If you believe the supplier's estimate for delivery..
Don Hanson

m21sniper

When you compare what a GM TH400 or Ford C-6 can take abuse wise compared to a typical manual(T-10 or T-5, etc), i think it's safe to say that yes, autos are potentially much stronger.

Herr-Kuhn

I don´t see anything superior in the 3-spd AT in a 928. Goldmember´s is holding up with 355 ft-lbs at the wheels though.