Gernby

iTrader: (1)

Huh? Are you talking about the Innovate Motorsports LM-1?

lobuxracer

iTrader: (2)

The basic concept is the ideal mixture is 14.7:1. However, it isn't possible to run that lean at WOT because you need a rich mixture to do two things: reduce combustion chamber temperature, and ensure you are not too lean and cause detonation. They work hand-in-hand.

The leanest I've seen an NA engine run at WOT without signs of detonation was 13.4:1, and it was a carburetted engine with no feedback, not fuel injected, running on oxygenated fuel. You need to have a lot of things working right to run this lean.

The OEMs all default to very rich at WOT because it ensures you will (almost) never run lean and detonate. Most turbo engines default to about 10:1, and NA engines 11:1. This means if anything goes wrong - fuel filter clogs, injector(s) clogs, fuel pump fails to deliver enough fuel, etc, the engine won't have severe damage from detonation and they won't be buying you a new engine under warranty.

Unfortunately, there is a lot of power lost to running rich. IME, one jet size rich or lean on the bikes I tuned means about 2% difference in trap speed in a 1/4 mile, which also translates to 2% hp difference. One jet size is a lot less than the difference between 11:1 and 13:1.

So, tuning the fuel to run at the ideal mixture for the engine is going to make more power than stock for sure. Here are the caveats/warnings:

1. Using an air/fuel measuring device that does not measure each cylinder individually may lead to running rich in some cylinders and lean in others without your knowledge and may lead to detonation in the cylinders running lean. Detonation results in severe engine damage (AMHIK).

2. Using a wideband O2 sensor may not give you the most accurate picture of your air/fuel mixture if the engine is misfiring (may appear lean when in fact it is too rich).

3. Changing fuel after "dialing-in" your a/f ratios may result in running too rich or too lean - it is critical your solution includes the ability to adjust target AFR automatically if detonation is detected.

4. If you do not heed the caveats/warnings, you could literally destroy your engine - crack the block, burn holes in a (the) piston(s), crack a (the) piston(s), break a (the) ring(s), etc. These are extremely expensive repairs, and the reasons why most people leave the tuning to experienced persons who have both the knowledge and the equipment to tune the engine as a complete system.

LSCJJ

iTrader: (3)

any news on this? its been a year! lol

nabbun

he's been using it for a long time now. that's about it lol

Gernby

iTrader: (1)

It's still running in my car, but it hasn't been "self tuning" in over a year since I don't have my WBO2 sensor installed in my HKS exhaust. I would love to spend a couple days to get it totally working again, but the new job, new wife, and new baby are higher priority.

maxnix

Good work, but with only an virtually unnoticeable 6 ft. lbs. of gain, it stands best as an example of how well Lexus tuned the engine originally.

Gernby

iTrader: (1)

It certainly wouldn't be fair to say that there was "an virtually unnoticeable 6 ft. lbs. of gain". Where did you see that in this thread? The only dyno test that I did was a couple days after I got it running. I spent weeks after that optimizing it, but never got back to the dyno before installing my HKS exhaust (removing the WBO2 sensor).

bad co

dont wbo2 let you run a 75% 93 and 25% e85 to get a higer octane fuel mix?

Gaugster

The OEM A/F sensors (Multi-Wire O2's) can make adjustments for using more ethanol. I ran what amounted to E20 in my vehcile and could see the fuel trims adding more fuel to make up for the lower energy that is in E85.

I think that Grenby has a aftermarket WBO2 that was installed near the rear of the vehcile. He just did not get around to adding a bung in his axle back.

Kurtz

iTrader: (1)

And unless you're in japan and had TOMs reflash your ECU you'll see no benefit to a higher octane fuel anyway.

Gaugster

This is probably true but I intend to find out for myself on the IS somtime. I want to try E30, E40 etc... just to see how the car reacts. At some point the fuel trims will max out and a CEL will be triggered.

I have read where other types of cars will advance the timing and actually get better gas milage then when using all petrol. It's rare and I doubt that us Mid-West ISx50 folks are going to be that lucky.

RocketGuy3

iTrader: (1)

Why would the car advance the timing with an all-petrol fuel? I thought ethanol increases the combustion resistance of the fuel...

2k2 R1

wow...guys, you see how much things change within an year. This man got a new job, new wife, and a new baby

Gaugster

Sorry, I had a typo and wrote "the" instead of "then" (or should be be "than"??)

Anyway, E85 is rated at about 105 octane so the fuel can handle more timing advance, Higher boost etc... There are a bunch of forums dedicated just to this fuel.

lobuxracer

iTrader: (2)

More base timing != good. Sounds like this fuel could use a different combustion chamber design to work well. Needing more base timing does = less efficient.