I have a 2000L with mods including a 2Ib pulley and a chip burned to suit.

Air/Fuel is below.

3900 12.2
4000 11.9
4100 11.8
4200 11.9
4300 11.9
4400 12.0
4500 12.0
4600 12.0
4700 12.0
4800 12.0
4900 12.1
5000 12.1
5100 12.2
5200 12.2
5300 12.2

I intend to change to a 4Ib pulley and dyno again to check the air/fuel before and if getting a re-burn. Is this a good idea? What is the air/fuel most going to change to with an additional 2lb's of boost?
I live at 5000 feet altitude, I was told higher air/fuel ratios are ok up here because of the thinner air. Any coments?

Thanks

 

Is there a tuner in Albq? who is doing your dynos? just curious.

 

I don't know but you sure do have some sweet azz A/F curves right now

--Joe

 

Thanks guys

Went to Dyno Edge in Albuquerque.

The chip was mail orderd from JDM. Gave him the location details, mods and the fact that best gas here is only 91 octane.

So any takers on the question about will the air/fuel change much with an additional 2Ib's of boost when I add the 4 pounder?

 

You are walking a very fine line right now. Myself I would fatten it up a little even with your current setup. I would rather give up a few hp to save the motor.

 

Nice to see a fellow Nem mexican on here. A/F look pretty good for our altitude. What were the power numbers? Im running a 4lber and chip right now myself. Havnt dynoed it yet. Send me an IM and maybe we can talk a little more and share some knowledge. Take it easy.

 

Bro, 12.0 is to lean..

Fatten it up to about 11.4 for safety. Hate to see you blow that motor. Tell your tuner you want a towing program which adds a lot of fuel.

 

If you add more pulley it will Lean up the A/F a bit and put you over the edge, you will have to richen it up for that.

I agree with Silver Bolt, be safe. I have mine tuned for 6-7 lbs of extra pulley. A 2-3lb upper and a 4lb lower, BUT I only run my 4lb lower in the winter just to assure a richer tune. I also run "2" ranges colder than stock (Denso IT-22's) to be even more safe.
The funny part is the truck runs awesome this way too
Ran a 12.8 and that was without Slicks, Bars, the Upper Pulley, Plasma Booster, Accu-Fab Throttle Body, etc.... I run only 15 degrees of timing on the street, and 17 at the track, on pump gas. My A/F was tuned to stay low 11's on street, and 11.8 on the track program at WOT. Never any detonation even now with week after week of teens, 20's and 30's we've been getting here in Long Island.

BE SMART
BE SAFE

 

Talk to a good tuner and go with that. The reply's you will get on the board are from people that live at sea level or close. We are at 5,000 ft. Right off the bat, our trucks are making 20-30 percent less horsepower and torque than sea level. They can take more boost, timing, etc.

 

Thanks thunder, Nice to see another high altitude L. I talked with my tuner today. He confirmed what I was thinking, That we can indeed take a higher a/f up here in the thin air.

I looked through a/f posts and found yours. Are you still running that chip? If so any probs? Also i guess like me you are running 91 octane gas here?

 

After i made that post I called my tuner of choice and had a lengthy talk with him. He confirmed what I was thinking about being able to use a more agressive chip up here in the thin air. He also agreed that my 13.6-12.9 A/f was a little too agressive. He reburned my chip for a 12.0- 12.2 A/F and 4 lb pulley. I have been very very happy since, no more pinging. Ive been meaning to put it back on the dyno but just havnt had the time. When I do Ill let you know how it goes. Yes im using 91 octane. Ive contacted a few other L owners in the area. If your interested, we should all maybe get together.

Drop me an email.
pagarcia@sld.state.nm.us