If you want to correct the A/F ratio, you need to get your car tuned. When I say tuned, not Hypertech tuned, but real dyno-tuned. The mail-order guys on this board do a very good job at tuning also from what I have heard. But before getting a tune, I would get a Cold Air Intake and headers. Those should help your numbers.

 

Yeah I would recommend the cold air intake and the tb bypass mod. Thats good for about 25hp.

 

I have already done the TB bypass, but it looks like a CAI is in my future.
However, would it not cause an increase in my car being lean since I am increasing the air flow?\

 

my motor has 160000 miles and i just did heads and cam, i dont have any problems...


btw my car dyno'd 280rwhp and 314tq with shortie SLP headers cutout, cold air, airfoil, hpp3...

 

There will be a small increase in airflow, due to reduced pressure losses and colder air. That increased air flow will be seen by your mass-air sensor, and reported to the PCM. The PCM will add the extra fuel to go with the extra air. If it miscalculates, the long term fuel corrections, based on feedback from the O2 sensors will make the correction. That's the beauty of mass-air EFI.

You adjust WOT A/F ratio with the power enrichment (PE) tables.

 

if your fans are coming on at those temps, i hope you have a 160thermostat, otherwise, you'll burn em out. With the kind of miles that motor has on it, i'd be pretty happy with those numbers

 

i also think those numbers support your mods.

there are really only a few bolt-ons that do anything for hp and the rest are scams IMO. so the 4 listed below will yield the best results. and of those you have 1.

1. headers
2. catback
3. CAI
4. cutout

 

Thanks again everyone!

I do have a 160 stat, btw.....

Well, I asked on the pullies on this board before I got them and the general concensous was they would help a little. One person even made the point that add all those "little" things up and you get something worth while (not bad advice).

Well, glad to hear my numbers were ok....I was just a little surprised.

So....Fred, on those PE tables, how to I adjust them (higher or lower)? What RPM's? I just do not want to mess anything up, so the more info the better.
Thanks!

 

You need to go on the LT1_Edit board and do a search.... there is a formula that tells you how to alter the PE vs. RPM and PE vs. temp tables to get a specific amount of change in A/F ratio. I don't use the stock PCM, so I don't know the formulas.

 

I only have the mods listed below and i got 274 rwhp and 310rwtq. A CAI so far is the biggest difference i have noticed in doing the small mods to my car.