Water Injection Thread

[Tom Sharpe]

Frederic Breitwieser wrote:

> <snip>
> For chassis setup and testing, I'll be using a N/A 4.1L block with an Audi
> FWD transaxle, which will be replaced with the Porsche G50-50 transaxle,
> with a build up to about 500 HP.  This is more than enough for my 2200lb
> target weight :)
>
> I figure 500 HP is more than enough (prolly overkill), and the Porsche unit
> will survive.  A friend of mine runs more than that through it, however its
> top RPM power, not off the line power (grunt) like the buick Engine.  I
> have concerns about 1st gear actaully.    (You are 2.20  correct )

Go for the stage II. You want to be able to accelerate from 100 to 150 like a
CanAm car.  Most transmissions are limited by torque in low gear (& second) on
the output side. Most families have different ratings based upon the low gear
ratio. As long as you don't hook it hard ( and I don't think 2200 lbs will
without tires, soft suspension and weight xfer (last two are bad for a road
racer) will hook up), it will last for ever. if you are worried, just use a
marginal clutch and replace it every year or so. (Or just keep your foot out of
it in low).

I use automatics and let them slip just a little in my 2400 lb street
thrillers. I also use street tires only (no gumballs) and have never lost a
transmission, converter, rear end, drive shaft, axle, or U-joint. ( and it will
pull the wheels!)  I have, however, twisted off a transmission input shaft and
a transfer case output shaft while truck pulling. I also replace the axles when
they show 180 deg. twist.

IMHO If you allow something to give and don't abuse them with the clutch, most
trans/axles will handle twice the rated torque in the higher gears. I worry
about the Porsche more than the Audi as the Porsche is designed for high RPM HP
and the Audi more for street torque. What is the Torque output of the
Porsche?)  Look at the diameter of the output shafts (pinion shafts) and
bearings, pick the larger.

Just my .02

One more thing about Turbo motors.  If your motor sounds funny and you pull the
pan off an there are a dozen pieces of piston skirt laying in the bottom of the
pan, it's detonation. Been there, done that, won that T-shirt.

Keep up the good work!          Tom