Ok, thanks. What fuel psi is the LT1 usually run at wot? 42-45? thanks again

 

I thought it was 43.5

Can someone verify?

 

The stock FP regulator is indexed to manifold vacuum. IOW, you can think of it as a 1:1 FMU. Base FP is ~42, but it will go up at WOT due to less manifold vacuum (more pressure). So, you will see a higher FP at WOT. But when calculating fuel jet sizes use the base FP. The change at WOT simply compensates for the change in manifold pressure and maintains the delta P, which is what drives flow. On my car, where the base FP is 55psi I have to use smaller fuel jets to avoid an overly rich mixture. The FP rises up to near 75psi at full bost, but just as with an NA car I calculate jet size on the base FP.

In any case, the difference in calculated jet size for 42 v. 43.5psi would be minimal.

Rich Krause

 

FWIW, like Rich mentioned, NX lists a pretty rich fuel jetting.

I get O2 values similar to running NA when I use 52/28. The 33 jet gives close to 1.000 readings!