Tuning 981 Models - When 400hp is not enough

ralphmusic · Dec 24, 2015

For the ultimate in power..

I wonder what you have to do to the suspension and brakes for this monster?

ralphmusic · Jan 17, 2016

As posted in the Cayman section, DeMan Racing in the USA have their 4.0L conversion running.

http://rennlist.com/forum...deos-and-feedback.html

Motorhead · Jan 17, 2016

So, where does the 520hp banner come from Ralph? I can see "only" 443.59 (wheel?) horsepower.

Even so, not too shabby..!

Jeff

ralphmusic · Jan 20, 2016

One assumes the 520 is calculated crank hp

Motorhead · Jan 21, 2016

Circa 80hp transmission loss Ralph? Sounds a bit excessive to me.

Jeff

ralphmusic · Jan 21, 2016

Motorhead said:
Circa 80hp transmission loss Ralph? Sounds a bit excessive to me.

Jeff

Perhaps it was hyperbole gain?

tscaptain · Jan 21, 2016

That doesn't look like an awful lot of torque (366 ft lbs) from a 4.0L turbo with 520bhp? The new 991 turbo has 540bhp and 520ft lbs (from a 3.8)[

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ralphmusic · Jan 21, 2016

Alan,

It is not a 4.0L, it is a 3.4L with a single turbo running at 4psi. On the HP v Torque, HP is calculated crank (wheel HP + transmission loss determined on run down) whereas Torque is wheel ft lbs.

The more interesting work on power is with three 4.0L projects, two are longer stroke using modified Porsche 4.0L crankshaft, stronger rods and different pistons. The third which is 4.2L has larger bore plus a custom crank, rods and pistons. Two of these projects are running in road cars. Effect reported is similar to the 997 GT3 4.0L which is a big increase in low down torque and another 40HP over 3.8L "donor" tune.

Ralph