FinanceMike

All top runs were best of 3 on the same dynojet dyno under the same conditions. About 90 degrees and humid.

Stock 411whp and 454wtq
ECU tune 444whp and 481wtq
SC pulley and box tune 449whp and 503wtq

I do not have any cooling mods. I expected more peak hp and tq gains from the ECU tune alone.

Any suggestions?

Dyno of ECU tune vs. SC pulley attached.

Hulk

Get a good HE, You are dropping power pretty fast, ask kustom2k1, he's in palm beach, he has a frozen boost HE, which is good

DVC

13:1 AFR at 4900 RPM....these canned tunes are scary.

Did you get a re-tune for the smaller blower pulley?

FinanceMike

Yes. This was the re-tune recommended by EC for the smaller pulley.

I went with the smaller pulley because my stock one needed replacement and for half the price, I figured why not.

The car feels good but I was told the gains would be larger.

DVC

Be careful. That AFR is a mess.

99lightning

remember thats on the dyno it will richen up a tad on the street its super lean at the bottom where it makes all its torque so thats great for breaking parts and up top that car is in the 10's afr on the street super wonderfull for those plugs. This is how you want it on a blower car coming into wot and across the board.

FinanceMike

I will get a custom tune.

That will fix the safety concerns with the a/f ratio but will it improve the hp/tq numbers at all?

AKnight55

Im guessing by s/c pulley run you were heat soaked, so that could have brought your numbers down

FinanceMike

I should have clarified. These runs were done on different days. May baseline runs, July ECU runs and Sept SC pulley runs.

About 20-30 minute cool down between runs.

berti_00

Who did your tune???

FinanceMike

EC for both the ECU tune and the SC Pulley tune.

Toadster

when I talked with Jerry during SF Dyno day - he said he spent 8 hours on the dyno with the S/C pulley and felt that it was pretty solid

berti_00

Well that makes me think twice about instslling that pulley if EC tunes not good

bstudey01

If he's heat soaked, over 120* intake doesn't the computer pull fuel/timing?? Could this be why the AFR's are too lean?? Or am I thinking backwards and the computer dumps in fuel when heat soaked??

Hulk

When ecu sees the iats are too high it will dump fuel

berti_00

Is this why his afr are messed

Hulk

Well it would help to see what his iats were starting and at the end
Remember he's still on stock cooling

claudiagoul

This is how you want it on a blower car coming into wot and across the board.

e55amgrocket

It pulls timing and adds fuel when IAT's go over 120 and again at 140 I believe it is. I would just have Jerry add some fuel down low in the RPM. Did you log IAT's? I bet That's part of the problem. Do a few 2nd gear roll on's and see how high the IAT's get.

e55amgrocket

I have to disagree with you. These engines (pistons/rings) are pretty sensitive and that's a lot of heat and cylinder pressure created low in the RPM. Recipe for disaster.

99lightning

i said that about the how i have the af in the graph i have posted on a heavy lightning i tuned the other day. You want to talk about a sensitive engine 2valve 5.4 ticking time bomb. that graph i have is how you want that af to look

DVC

I wouldn't let you touch my tune with a 10ft pole. I hope you step up when that guy vents his block on a cold day.

GT-ER

Actually, I've always tuned slightly lean at peak torque and then richen it as power goes up to peak hp. Works great.

e55amgrocket

Works great as long as the engine can handle it. Not sure what kinda cylinder pressure these engine see being lean at low RPM where the torque is but thats where a lot of heat/cylinder pressure is made. I personally don't do WOT runs from 2500 RPM or even dyno pull's starting that low but for peace of mind and longevity i would add some fuel down low.

GT-ER

Oh...and by lean I mean 12.5 or so...not 13's...lol.