EFIDynoTuning Forum

no , should be no more than about .1 less than fn875 for your idle rpm

not uncommon but so long as its not a major correction

Fn875 is set to 1.00

Reading the parameter comments on Ithbma I converted the maf flow at idle from kg/hr to lbs/min and came up with .918, so that’s what I set it to. Does that sound right?

What effect will this have? Because I’ve run this car for years with it set at zero? lol

I’ve got everything dialed in nicely but just have a problem with heat soak for some reason. I’ve noticed my iat’s as high as 140 on those hot restarts. I decided to play around with FN300 ACT lambse multiplier. I have it set to add fuel above 110 degrees and it’s helped that restart tremendously.

thats odd most engines dont heat soak like that

where is your iat located?

Yea it’s always been this way since I’ve turbo’d it. I’ve done things to help the under hood heat over the years and it runs fantastic overall. But the delayed hot restart has still been a pain and is the only thing keeping her from perfect.

Iat’s come from my pmas maf

I dont understand, what is a delayed hot restart?

You have to hold it in the crank position for a long time?

Or are you meaning it cranks and stalls ?

the act multiplier is global, you dont want to use that as youll hose down the engine when it gets hot out and temps climb while making a pull

No I meant after it sits like I described earlier in the thread, the heat soak issue.

I realized that and figured it would be something I’ll have to keep an eye on.

Is there a better way to do it?

You never described what its doing though. The first post you said it was lean and stumbly adter sitting an hour. Third post you said adding enrichment makes it rev higher.

If its lean and stumbly after it sits yet revs too high when fuel is added then youve solved the problem its obviously needing that fuel.

Im not uderstanding what your wanting to achieve or adjust for if youve already fixed the problem?

Sorry guess I haven’t described it well.

I’m wanting to find a way to add extra fuel only at startup when iat’s are excessively high.

The ACT fraction for startup enrichment would be the only logical way.

You could set it to .8
youll loose overheat protection though.