andy-gts

Nice numbers Ted, I am sure its a fun ride!

Mike Frye

Does anyone else think it's weird that the video shows the front straps holding the car through the wheels?

Isn't that going to do bad things to your suspension?

Rick Carter

I'd like to know how to do this.

BReyes

Nice and easy! At least you make it sound easy. I like the plan to keep it reliable.

High performance and long term reliability is the best benefit Porsche can provide. Good mod the SC. It takes her to another level. Thanks posting some numbers.

As always, now that its sorted what (other car) to do.

Regards,

hacker-pschorr

That's very common, at the track we use the stationary cars to hold the canopies down via their wheels.

If you didn't use the wheels you would most likely tie the car down with the lower control arms anyway. On an S this could put pressure on the lower spoiler.

Cosmo Kramer

Not too much force going backwards, just holds it from bouncing back when it shifts gears. Tow trucks do the same thing.

The switch just ties into the WOT wire going to the LH and the other side of the switch goes to ground. Under vacuum the switch is open, at 0 vacuum it closes and puts the LH into open loop.

One of these switches will work, I just need to contact them to make sure I get the right spec. The have a high/low vacuum port, I guess you can just cap the low port and T a vacuum line to the high port.

http://www.newark.com/jsp/search/pro...-OP&CMP=AFC-OP

PorKen

With a vacuum switch, you'll need a cutout for when the engine is cranking, or the LH may go into flood clear mode.

Check with Alan or someone more knowledgeable, but I think the simplest way to do this, without using a relay, may be to connect the ground of your vacuum switch to the (purple?) starter wire through a large resistor.


A fancier way would be to use the MAP sensor in the EZF. There is a 0-5v output from it on (the empty) pin 21. Use a voltage switch to trigger the WOT.

(Jaycar Voltage Switch)

I'd like to have the frequency switch from there for a road speed trigger.

Cosmo Kramer

The one I was looking at was adjustable for pressure (should have mentioned that!), so if it was set to close at say 1 psi it wouldn't go to WOT while cranking.

PorKen

Oops, I didn't read your post carefully (still nursing my first coffee).

Mike Frye

Gotcha. I've only been to the dyno a few times but I'd never seen it done like that.

When they strap it down they have to tighten up on the fronts and(or) backs to hold it down on the dyno drum. I just thought that was a bad angle. I guess if you can tow a car by the wheels you can pull forward on them without doing any damage.

We now return you to your regularly scheduled thread.

PorKen

Are you logging the WBO2, or just looking at a gauge when you see the 12's? The 'acceleration pump' shot will look like it's getting rich, but it doesn't last for very long.


The AFR curve looks like a typical S3 at WOT with the stock chipset. Close to 14's at 2500 getting richer as rpms go up. Might be able to make it perkier off the line by richening up the WOT map at low rpms until the boost kicks in. Max N/A torque is at 2700.

If dyno guy was in closed loop at the beginning, it would have likely been in the 15-16's (or worse) to start?

mark kibort

the numbers are good, the curves are not that good. flat torque is not what you want. you want flat HP.
that curve is exactly the same as the peaky HP of a GT3cup car. (flat torque curve)

I have almost the exact same HP with a flat HP curve. the effect is a lot more torque down low and more ave HP. is there a way to increase the boost in the lower range and taper it off toward the top?

Mk

Cosmo Kramer

Just looking at the gauge, but it isn't just the accelerator enrichment. My FMU adds about 10 psi starting at 2 hg, but in closed loop the O2 is trying to maintain stoich, but loses the battle somewhat and it ends up in the mid - high 13's. If it is taken out of the equation it will be much better.

My old FMU, a standard Vortech unit, didn't add any fuel until about 2 psi and it was crazy lean at tip in, 15-16 just like you were saying.

Welcome to the world of a centrifugal supercharger! They build boost with RPM unlike a roots or twin screw that give it to you right away.

mark kibort

Its nice that it is smooth and consistant. crossing at 340hp means nothing. Its a peakyHP, flat torque curve. nothing good about it. whats good, is that he is at 370hp! thats good!

AO

Wouldn't we all...

Mine is adjsutable just the ine Ted is talking about.

Basically you use this pressure switch to tell the LH that you are in WOT mode. Don't touch the EZK. Then when you hit any amount of boost it switches to the WOT map and... BAMN! you're at 12.0 AFR. No tip in.

There's a particular name for these switches, but I forget. Toumov mentioned it in a recent (1 month) thread.