hey, i just finished my mod to the fpr and the firt setting was 1/4 of an inch higher than stock and lets just say that was way tooo much cause it was idleing at like 2500 rpms... took it back off and adjusted it to about an 8th if that and it idles fine but if i made it go to the 1/4 diffrence wouldnt it be richer??? or how exactly does that work... i know the higher the platform the more pressure but doesn't more pressure mean more gas squirting out?? and if so shouldn't i make it a little leaner for more power?? well tomorow i will finish adjuassting it so any info you all can provide will be greatly appreciated!!!
chris

 

Yes, higher fuel pressure = richer air/fuel ratio. Generally speaking, making it run leaner than the stock setting (somewhere between 9-12psi) will not make it run better, nor will making it run richer. It usually depends on your mods, including timing adjustments as to whether or not you need to increase the fp. Do a search on your mods to find what fp people are running in conjunction to the mods.
As far as idling at 2,500rpm, that sounds wrong. I run a Holley 670 w/ 57pph injectors on an l03 that has stock innards. It runs rich to about 3,000rpm, even at the lowest fp setting and a chip for 55pph injectors. However, once my engine warms up, the idle is at 750rpm, regardless of what I have the fp set at(it still runs rich when warm). Try doing the diy AIC adjustment and see if that helps, because you can't tell whether or not your running rich mearly by the idle.

 

whatz an aic adjustment??? remember i am new to the chevy game i was a nissan man!

 

Ah.....I'm glad you've seen the light
IAC is Idle Air Control. There is a tech article on how to adjust it on this sight under technical articles. Try it and see if it works.
Also, keep in mind iac's do go bad as well, so if the adjustment does nothing, than it is possible your iac is bad.

 

and check that you didnt smack or bump the 4 wire harness that plugs into the IAC. I broke one of the wires loose and the thing idled nearly to 2000. Had to jerry rig it with alligator clips, a pop rivet and electrical tape while i was waiting for a replacement to come in.

 

it works fine now after i adjusted the pressure back down. i am still not sure why it did that? but i turned it down to between the stock setting and the setting i had increased it to and it works great!!