What are you guys running for fuel delivery and what sort of duty cycles are you seeing on pump gas and race gas. I have 780s right now but feel I might be pushing them close to the edge on race gas, what do you reckon? Walboro too but everything else is stock.

Scorke

 

i have ams 1000hp fuel system and rc1200cc injectors.

 

I'm seeing upper 80's for duty cycles on PTE 780's on a 50 trim, stock block and head, cammed, with AMS Vsr, Walbro, on pump gas with a/f's of low 11's. Redline set at 7800. I think you'll need bigger injectors at a minimum.

 

What power/boost are you seeing those duty cycles at?

Scorke

 

IA Performance went with the recommendations of David Buschur. He recommended the dual pump system and an adjustable fuel pressure regulator. I have a 2.3L, Stage 3 head and GT35r. Before this was only a single Walbro 255lph and 1000cc PTE's it was running in the upper 90 duty cycle on 33psi of boost.

 

Really upper 90s at 33 psi, what power were you putting down?
I am thinking 1000's are the way to go, I don't want to mess wit the duel pump, fpr maybe.

Scorke

 

360 whp on a conservative DD, or about 410-420 whp on a dynojet. This was at 22#'s boost.

 

Jesus i have made 490 480 on my 780s on topspeeds dynojet at 30 psi. I had room to go, im thinking 9 somethings.

Scorke

 

563hp and 513ft/lbs on a Mustang Dyno, don't know what that is on a dynojet! WIth the new pumps, fpr and new clutch I think low 600's is possible.

 

im at 441whp on our mustang.... 850 cc's... im at about 70-82% IDC... depending on the rev range...

this is on pump gas... I also have 1000's in the cabinet, and will be going to the upgraded walbro for now (the modded one)

cb

 

yeah, tell me about it. Either the DD is extremely consevative (overly consevative), or maybe my wideband was reading conervatively, or my system is whacked out. I did get another set of new 780's on the off chance the first set wasn't flowing properly. Same result...... upper 80's on duty cycle. I'm running about 47'# base fuel pressure to boot.

Per RC Engineerings injector calculator, it predicts my injectors almost perfectly at a bsfc of .65. But alot of people seem to make more hp on smaller injectors and lower duty cycle than my example.

I'm sure you've seen this, but here's a convenient link for others

http://www.rceng.com/technical.htm#WORKSHEET

 

Yeah damn, sounds about consistent with what I ahve heard abotu 780s. I feel like 850-1000's will be a good comprimise for what I am looking to do, maybe 950's.

8urvtec sounds like your setup worked pretty damn well.

Scorke

 

Scorke, that is all before the twin pumps and fpr! The new stuff is suppose to be installed next week, we will see new numbers I am sure after they retune!!!!!

 

i have 1000cc's in my car now, and its seems to be alittle overkill to be honest for pump gas. i think i over shot it with the that size, But, i think that i might be in the market in for a set of 880s... Im on the stock ECU.

If your running AEM the injector driver isnt as efficent, which might yield the need for a bigger injector, if your running the stock ECU too, then i would suggest 880s

 

AEM or not I have heard from a few big time tuners the Injector driver box is a pos and is pointless.