Paul Waterloo

I had the car tuned on a dyno a little more than a month ago....it wouldn't even run right, and the guy leaned the car way down, it was running too rich, 11 runs later it did 280 HP and 290 lb-ft of torque at the wheels at 15 PSI. I don't think I want any more power right now....no need to turn the boost up, but it still runs a little rich at some points, a little less than 12.5 AFR at some areas. So some could be gained from there.

But the real issue was low throttle applications, the car had a few significant dead spots, specifically at 2500-3000 RPM, the AFR would jump up to 18 or 19 or even 20, I would just avoid those.

Well, I put the car up for sale this week, had an interested party, we drove it a few times, and it has an issue with these dead spots and the AFR at idle since I've got the car is always 10.1.....not good. I thought something was wrong.

Nope, just needed a tune. This morning I played around with the software and figured it out....first the idle in the garage, and then the low throttle tunes on the street. I made at least 20 "local" adjustments to the map. Drive the car with the computer on, the cell that is active "lights up" or changes from a clear background to a blue one....so it's dancing all over the place. While driving, watch the wideband, once it starts leaning way out, figure out the area where the dead band is on the map (by keeping it right there and seeing which cell is "light up"), click on it and pull over. Make "local" adjustments to fuel trim on the map in that area (it becomes obvious what is wrong after doing this a few times), write the revised map to the ECU and do it again.





I got the thing DIALED in at low throttle applications from idle all the way to 6,000 RPM.....oh so cool!!!

It's not hard once you figure out what you need to do....it's just hard to get to that point....it's very, very cool.

BTW, it's a split second piggy back timer.

Here is the AFR at idle.....and it idles PERFECT. No more tendency to want to die or die....it's perfect.

lart951

12.5 AFR is not rich as a matter of fact is borderline lean under boost at high rpms you want to see no more than 11:7-12:1 Max

Paul Waterloo

Thanks....that's pretty much what I am running at 15 PSI. Maybe down to 11:1.

black944 turbo

I agree with Lart on the afs.

So are you keeping her now?

mdj577

Nice! I remember riding in your car. Beautiful and fast. If I was in the market for a 951 right now I would have you at the top of my list.

If you don't end up selling it, enjoy!!!

alxdgr8

Cars definitely react differently on the street and dyno. A dyno is great for full throttle stuff, but you always have to do some street tuning to really get the car driveable...as you found out. Good to hear it's running great!

Paul Waterloo

I just brought it up to a car GTG this morning, OMG, the thing is soooooo smooth! Found so much power from 1,5000 RPM to 3,000 when the boost kicks in. And when it was cold....it ran so f'ing good.

So good, that I'm about 95% sure I'm not going to sell it....at least that's what I'm thinking now. It's a special car and everything is done to it.

User 52121

So.... inquiring minds want to know: what all did you change in your tune?

And glad to hear you're keeping it. We'll have to meet up one of these days for a bier.

Paul Waterloo

Just changed the piggy back signal....where it was too rich (idle), I leaned it out, where there were dead spots on acceleration, mostly at very light throttle, I added fuel. You do this by adding or subtracting from the number presently in the cell, just change it like you would in a spreadsheet, then write it to the ECU with the engine off.