how lean is too lean?

[JayRolla]

Thats what I thought because than my tune would be all messed up. I guess thats my lo throttle issue right now but my before the wire went loose the tune seemed the same. So I heard you say glenn I can change a switch on the back of the AEM EUGO so I can feed the ecu with the wbo2? Would this change the reading on the wbo2 also?

Hmm...... maybe i should tune a tad leaner in the lo throttle areas. Doesnt running leaner like that help clean the combustion chamber of carbon depsites.. Long as i dont knock id def perfer e leaner tune on this old motor with all its blowby and what not.

Too bad you dont have e85 in your area because the stuff cleans the motor so well. There is a old thread on rmdsm.org where a guy took an old 150k mile motor and ran e85. If I remember right he pushed the stock 6bolt hard as hell on e85 till he broke a rod in about 5k miles. After tear down the motor looked perfectly clean. You could see inside the intake mani where the fuel sprays and it cleaned everything to a shine. Stuff is awesome, no carbon build up at all.

 

[Ravenous]

This is a great thread guys, gas mileage is definately something that gets overlooked on these forums. I would like to try to get up to 30mpg on E85. I think it can be done with the right tuning and mods. Shoot, if pneumo can get 53mpg on gasoline it should be completely feasible... Right?

 

[wishihadatalon]

Wow I didn't see that mileage. I saw the epa ratings and dismissed it. The 45+ is very impressive.

 

[xxShaneOmac]

Im driving at 14.7afr 2.7k rpms in 5th gear.

I leg off the gas completly to just coast or downshift or what ever reason and my afr drops to 11's and then is back up 1/2 second later.

So this seems to be what you are explaining.

Altho ARRGG I just see $.10 $.20 dropping everytime that happens.
At $4.89 a gallon for supreme I feel like I should't let off the gas! .

 

[Black_Bullet]

Im driving at 14.7afr 2.7k rpms in 5th gear.

I leg off the gas completly to just coast or downshift or what ever reason and my afr drops to 11's and then is back up 1/2 second later.

So this seems to be what you are explaining.

Altho ARRGG I just see $.10 $.20 dropping everytime that happens.
At $4.89 a gallon for supreme I feel like I should't let off the gas! .

I hear ya, I take a lot of corners fast just because I dont want to let off the gas; or loose mommentum.
I hate when ppl who are driving in front of you almost come to a damn near complete stop to make a simple turn.
Im one of those ppl though if I see a light changing red in front of me, even if its still a bit down, I will just let off and coast all the way till I reach the light even as cars are passing me because Im hopeing it will turn green again before I come to a complete stop .

I skip gears sometimes to limit shifting, like Ill go 1st 2nd, 3rd, fifth .
I skip gears a lot, and when driving I try to keep my acceleration at one position, I dont back on and off the throttle a lot because it burns my gas, just try to keep your foot steady, and put your windows up on the highway
( URGH I have no A/C)
and obviously you want to stay out of boost...
Extended closed loop operation also helps a lot if you hit the highway a lot and like to drive a little fast like I do ( 80-85mph average speed.) This feature is normally done by ecu eprom chip...

Oh and if you have the will power to turn your boost down, then do it, I found that driving with the mbc all the way loose for the least boost possible, even if I didnt boost at all, there is a gain in mpg because the turbos spool slows down a lot, were as when im driving around on my 25psi tune Im going into boost by accident anytime I give it gas in 4th or 5th gear. I get full boost of 25psi by 3300rpms on this thing, and I can actually see the benefit on a bigger turbo for the lag.