msobota

I'm going to be brief because I worked (along) on the 993tt until 3am - but here is the dyno run.

The buildup -

Powerhaus K24 Turbos - modified for Autothority
New ECU
Apex Boost Controller - (boost to 1 bar)
Hi perf exhaust
Cleaned out Cats

Before the upgrade - 380hp on the dyno
After - 500hp on the dyno

But - The car seems to have trouble sustaining the power. We had the 5 bar fuel pressure regulator on the car but noticed the mixture was too rich - returned to the 3.8 bar stock part and the power shot up sinificantly and stabilized to a greater degree.

I am ready to pick the car up - satisfied - but would still like some suggestions on how we might tweak the setup to hold on to a greater degree of the power until 7000 rpm.

Mike Sobota

msobota

I posted the photo to webshots - follow the link.
You will need to paste the link together to be one long line in your web browser.

Mike

http://community.webshots.com/script...93900973SHnhlN

viperbob

A few questions. What octane fuel did you use? What ECU do you use? I am not familiar with the Apex boost controller. Does it have an adjustable selection to keep the wategate closed tight until a certain boost level? In order for some of the boost controllers to not spike past the selected max boost, they start bleeding off some of the pressure real early on the way to the max boost or 1 BAR in your case. This may account for little to no gain on the curves until 4000+ RPM. It may also explain why you can not sustain that level.

Nice overall gains though...

Q

What was the air / fuel ratio when it was too rich ?
What is it now ?
....I can't quite read it on the dyno sheet

Q

SPR

that's weird you should be running that 5 bar regulator. I would say you have some weird ecu? Do you have the stock diverter valves? How are the k24's modified maybe their wastegates are malfunctioning or setup weird. also using a boost controller after the ecu is usually not the best thing to do.

vrus

If you are running the stock diverter valves, get rid of them.. They are plastic and cannot hold boost very well.. Pick up a set of the billet diverter valves (Bailey or equivalent); it will hold boost alot better.

Also, you should be using the 5BAR FPR.. the stock one does not provide enough fuel pressure to meet the requirements of your power level..

Did you have a Fuel Pressure gauge hooked up while on the dyno? Or an Air/Fuel gauge? Careful you do not lean it out. You will end up with a very expensive rebuild on your hands.

KRA993tt

Mike

you have a PM

msobota

So - The final power buildup is:

K24 Turbos - w sport compressor wheel and clipped exhaust wheel
Cartronic ECU w Autothority software
BMC high flow air filter
Bailey Billet Diverter Valves
The boost is 1 bar.

The air fuel mixture was reporting around 100 and down into the high 90's with the 5 bar regulator and the power was in the mid 400's. Once we returned to the 3.8 bar fuel pressure regulator, the power came up to 500 and lasted longer and the fuel air reported around 120. Sorry I cannot be more specific. The next day, we removed the APEXi boost controller with no change in power.

I would like to see the power hold for longer into the higher RPM's but the car is a joy to drive and the torque is unbelievable. Having 500 rear wheel horsepower and 525 ft lbs of torque at only 5000 rpm is very nice.

Thanks for all the input.

Mike Sobota