BLUEBYU

iTrader: (1)

Before my 5.3L TEA head install, I was running approx. 41 lbs at 6400 rpm w/ just the cam. I thought I would see a gain w/ the head and LT setup...but now after getting the AF pretty close I am seeing mid to low 30's at the same RPM. Why is this? Is it because of the lower volume heads?
Any thoughts here are mucho appreciated.

<small>[ April 05, 2003, 11:45 PM: Message edited by: BLUEBYU ]</small>

BLUEBYU

iTrader: (1)

Anyone...I know the hp is there, but less MAF and injector duty to me does not equal more HP.

BLUEBYU

iTrader: (1)

Stumped? Me too.....there has to be someone who at least has an opinion.

Richard@WCCH

iTrader: (3)

My heads and cam car showed a 16% increase in airflow through the MAF. Stock, the MAF flow was 263gms/sec. After heads and cam the MAF reports 305gms/sec. You should definitely see an increase in reported air moving across the sensor at the top of the gear shift. Perhaps check for airleaks?

Good luck,
Richard <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

BLUEBYU

iTrader: (1)

I did not change the MAFS in any way. It is a Granitelli. If it is unmetered air the car would not run/respond like it is now. I think it is due to the head volume change...5.7L to 5.3L. I also may have been running rich prior to the head swap and did not realize it. My O2's were in the range of .93 and injector duty was around 75% at high rpm WOT. This would demand more air than if it were leaned out. I now have RMS "mail order" programming for a H/C setup and am showing O2's around .8 and injector duty about 65%. I am getting a fresh dyno tune w/Edit Monday by Raging Motorsports (btw, the new dyno rocks!!!) to eliminate my MAFT tuning of 6% lean. Am I on the right track here?

<small>[ April 06, 2003, 01:17 PM: Message edited by: BLUEBYU ]</small>

C_Williams

I have suspicions that the GMS, without a screen, does not deliver the correct readings.

That being said, I think getting LS1 edit tuning is the way to go. Please keep this thread updated with your results.

BLUEBYU

iTrader: (1)

Did you go with 5.7L heads? I would know if I had any air leaks....it wouldn't run as good as it is now. The car is strong and runs like a champ! No codes...no KR. Anybody else?
TIA

C_Williams

Do you have a screen in the MAF? A friends car I tuned showed a max of 320 gm/s with -8 trims and after installing the stock maf the meter now reports 355 gm/s with the trims responding downward to -2.

Sounds like you must have un-metered air getting to the engine, especially if you are making more power than before.