nuclearfishin

Finally got the car on a dyno today and confirmed my suspicions, the car runs as good, if not better on pump gas than it does race gas. The race gas file is green, pump file red. It's a giac tune. I data logged a bunch of numbers but haven't had a chance to go through them yet. Will post durametric files when I get a chance.

jaycm3

good numbers..any tiptronic tune or stock tip programming?

nuclearfishin

Stock tiptronic programming although someday I may consider a tune for that, I just haven't met anybody that has it and would like to get honest feedback first.

nuclearfishin

As a side note, does anybody know why rpm's drop off sooner on the race profile compared to pump? I would think it should be just the opposite.

AudiOn19s

How did you swap between fuels for the different runs?

MKIVdan

Very nice! what is your fastest ET with this set up?

elite1

I'm not familiar with dynos but, I thought I would see more with your setup.

By no means am I trying to discredit anything but, you ran some really decent times over a year ago.


Timing may have to do with your drop off for file comparison.

nuclearfishin

I agree 100% which is why I wanted to get some numbers on the dyno. I was running right around 11.1-11.2 with the pump profile and about the exact same with the race gas profile. This session confirmed my suspicion that I wasn't really making any more power on race gas. From about 5700 rpm's and up, I'm making more power and torque on the pump gas profile. I'm hoping the durametric numbers will help answer why.

nuclearfishin

I ran the first 3 runs on the race gas profile and then switched the tune to the pump profile with the same fuel, 100 unleaded. The main difference between the two profiles is the timing is advanced on the race gas profile.

jaycm3

What octane are you running while utilizing the race file?

nuclearfishin

It was 100 unleaded but I added a quart of VP octane boost which is supposed to raise the octane by another 8.

AudiOn19s

Interesting. It's my understanding that the GIAC tune works similarly to the OEM tune in that it will adjust timing within a defined range up to a certain point until any knock is detected. My understanding is even on the stock tune the car will maximize timing / power up to around 96 octane and then not advance any further.

...thus I'd bet your pump gas tune numbers were a good bit healthier with 100+ octane in the tank then they would actually be with just 93 in the tank.

Macster

If my reading comprehension isn't completely in the toilet if green is race gas and red is pump gas the green HP number is higher than the red HP number.

Looks like race gas vs. pump gas while both HP and torque start up at higher RPM they go up quicker and remain higher and flatter with the race gas.

The drop off at higher RPMs could be the race gas might be a bit stale. A fuel test in EVO some years ago found race gas in a stock turbo-charged car was ok at lower RPMs but really came alive at higher RPMs and just blew the pump fuels into the weeds.

Data might shed some light on the drop off too.

MKIVdan

in my opinion the power seems right. The 450hp - 468hp was to all four wheels right?

CincyScott

As an aside, the dyno at TiC reads low usually. They use it more for seeing improvement/loss than for sheer power numbers.