Bret:

Every time I recommend a large injector, I get a raft of **** from a few individuals who feel that the way to size an injector is to run it on the dyno until it can't supply any more fuel, then start cranking the fuel pressure up. When that fails, I guess they begrudgingly go to a larger injectors. Their "proof" that they are correct and I am wrong for using my silly numbers rather than real dyno experience, is that they are making 450+ flywheel with stock 24's, and their engines make more power than my engine, so obviously I don't know what I am doing . I just let my engine run on the grossly oversized 78's, wishing I was smart enough to figure out how to make 500HP on stockers.

The "0.08" factor uses 0.50#/HP/HR and a max of 80% DC. I guess I'm trying to make it a bit less conservative, assuming an 0.48 BSFC and 85% DC.

 

I bought their #37 Racetronix injectors, work fine, set the inj constant a little higher and zero'ed out the PE table, and I had a near perfect A/F under WOT and a awesome A/F from idle to 2700.

Its all in the tuning in particular the VE tables

 

Fred,

I just modified your 0.07 factor by adding in a 15% driveline loss. I hear you though on this

"Their "proof" that they are correct and I am wrong for using my silly numbers rather than real dyno experience, is that they are making 450+ flywheel with stock 24's, and their engines make more power than my engine, so obviously I don't know what I am doing "

BTDT

A 42# injector will not be a problem at all.

Bret