prscarf

ok gents here's the question:

i have two of the same chips except one has a bpw of 142 c/w a tuned ve table to match. i also have another chip, which should be used for my displacement engine, of 115bpw c/w with a much higher numbered tuned ve table. now, heres the question what problems are concured if you use a higher bpw and just compensate with a lower ve? i have used both and can maintain a close 128 for both, though it actually runs nicer with the higher bpw. everthing else on both chips are exactly the same. plug cuts are a nice light copper colour at 142bpw. the lowest number on the 142bpw ve table is 38 and high of 79.

383 stroker, 64cc 23deg trickflow alum.heads c/w weiand xcelerator single plane, adapter, cam is an extreme 4x4 comp. Cam. 12-235-2 grind ( .447/.462 lift, duration 210 218 lift @50, 111 lobe separation) . unit has hypr. Flattop floating pistons, eagle cast crank, 5.7eagle rods, bal.to 0.5grams, 10.2:1 comp. Headers c/w 2.5” flowmaster exhaust. 16147060 pcm, $85def
454tbi 80lbinjectors

Grumpy

See which one works best at the temp extremes. <g>

prscarf

again, because the weather is getting cold, the 142 runs better for morning starts.

Grumpy

Again?, OK

Extremes has an s at the end.

Starting to sound like your mixing cold start AFR with VE table.

Grim Reaper

I agree with Bruce, if increasing your BPW really helps with cold starting, then it sounds like you need to work on your "Cold Start AFR" tables and possibly your "Cranking Pulses".

You may find that "tuning" for the cold weather and not using the proper tables, that you may have "hot start" problems due to excessive richness.

As for your "best" BPW, you should try and use a value as close to your real value - same with Injector Constant for port injection.

prscarf

cold crank is not a problem and my open loop afr is very close to the close loop afr when it goes into close loop, i don't notice the change. it just runs smoother with the 142bpw. its almost like it the engine is starving with the 115