I finaly went to the dyno, but I came out with numbers lower than expected.

These first couple of runs where from the winter tune.



The A/F ratio came out to about 13. WTF, this is suppost to be the WINTER tune.

This is the normal street tune.



This tune ran a little richer, running just under 12.

I find it odd that the winter tune came out to be leaner than the normal street tune, doesn't seem right. Maybe somebody from JDM can chime in bacause I got the tunes from them

My biggest problem is the power. The best run I made was 405.74 hp and 477.51 tq. I was expecting in the area of 420 hp or so. I know heat kills power, but it couldn't be that bad could it? You can see what the conditions were when I made the runs. Help me out here, could something be wrong?

 

i bet the ported eaton is killing your PEAK torque numbers. Happens alot. Did it on my truck too.

The heat makes a big difference too.

Are you tuned on the new SCT software??? If not..........get it.

 

I was gonna come down there but my son wanted to see Herbie. I had to do the family thing. At;east you got over 400!

 

What can help with that, more boost? I got the 9100 Microtuner, got it around the time it came out.

 

with 4lb, apten port, cold air, throttle body, chip, silver bullet exhaust I made around 425hp/517tq. Definitely with your mods I think your numbers should be higher. But then again, diff. dynos will produce diff. numbers it seems.

 

I wouldn't be disappointed with those numbers. I went to the dyno about a week ago and was expecting to make 400 and left there with 380whp. You can't believe everything you read cause all trucks are different.

 

I think looking for 420 was a little too optimistic. I've been through 4 dyno days of 16+ trucks each, and generally your combo does 400-410 on a street/93 octane tune. If you got a race tune for 100+ octane, you might have made your goal.. All dyno's and trucks are a little different, so don't worry about being 2 or 3% off what the best trucks put up.

As for the winter tune, you need that adjusted. I'm sure the timing is set a lot lower though, so it probably isn't something to be too worried about.

-Mark

 

When I got my truck dyno'd at total performance my af was 13 as well, just with a ported eaton, cai, and T/B. I think their wideband bites the big one.
Just my .02


Nick

 

even on a winter tune with minimal timing, power should be significantly higher with a 13 a/f ration.

My numbers with the ported and similar mods was 422/511.

Got retuned on the sct software and went to 437/532. My numbers are STD corrected both times as far as comparrison goes.

This was with a a/f in the 11.8 max area.

 

I'd disagree with your first statement. Lower timing probably cost him 10 HP and 1 A/f higher isn't going to make over 10 back. Your numbers (if running a 4lb pulley) are at the upper end of what our trucks make. That's lucky for you, but doesn't mean his numbers are off.

Where did you dyno at?

-Mark

 

If you suspision the wide band is off, that can make a big difference. I dyno'd on one that was off and not only did I not make the numbers I should have, I was told my injectors probably needed replaced as well as my mass air. The tuner had put all the fuel he could in and still couldn't get the af's out of the 12's. After finding the dyno's widband was off (others had problems)I bought a WBC and found my af's were in the hi 9's low 10's When I went to get re dyno'd my af's were so rich they didn't register. After being tuned on another dyno everything is now correct 11.7 af flat across the board and nothing needs replaced final #'s 433.9 rwhp 513.7 torque SAE. mods 6# lower steg port with usual bolt-ons

 

hey buckstop that a/f curve looks perfect!

 

They take the A/F readings by putting small pipe like things in the exhaust tip that picks up some of the exhaust. Then it goes to a box on the floor with a 02 reader. I don't know how other dynos take it, but this is there way.

 

thats correct, but if the operator doesn't take care of his equipment, clean it and change filters then what happened to me is the result. The dyno I had the problem at not only hadn't cleaned his unit but ther wasn't even a filter.

 

Thats Sal (PSP) magic on the new AFR's