bumping up fuel pressure to [email protected] idea???

[NJdsmguru]

I'm currently running RC 550cc injectors, 2g mas, afc, Walbro 255 fuel pump, and B&M fuel pressure modifier. My current turbo Trbochargers.com TDo6 Godzilla flows 650cfm @ 15psi ,along with my fmic, and addition of hks 272 cams. I'm going to be definately running lean. So i figured I'd bump the fuel pressure to 55 psi w/o vacuum line connected to add some more fuel until I can afford some 660cc injectors and a real AFPR. With fp bumped to 55psi injectors 550cc injectors
output should be bumped to around 622cc. Gonna keep the boost lower than 20 psi on pump gas. Good idea?????

 

[1fast97gsx]

sorry ... can't help much .. but I have some 650s for sale

 

[90AWDTalon]

I've been running 50psi for quite sometime now. When I was still on my stock injectors I was running 60psi. Just remember when decideing what base fuel pressure to run to add your boost to it so you know what you're total fuel pressure is and if your pump can handle it.

I came up with 671cc with your proposed setup.

sqrt( 55/36.9 ) * 550 = 671cc

 

[NJdsmguru]

you came up with 671cc for my proposed setup. I'm not going to be running more than 22 on C16. I'll keep boost like 15-16 during street use on pump gas . Thanks man for your help.

 

[smokinstorm]

I've got my fuel pressure cranked up as well because I'm still on the stock injectors. Just get ready for the car to run extrememely rich until the boost comes on and also be significantly weaker in off boost situations. If you stand behind my car at an idle, it actually sounds like there are cams in the car. The fumes will make your eyes water. Can I recommend this to others? Not really. It's a crutch to get you by until larger injectors are in the budget though.

 

[kpt4321]

Originally posted by smokinstorm
I've got my fuel pressure cranked up as well because I'm still on the stock injectors. Just get ready for the car to run extrememely rich until the boost comes on and also be significantly weaker in off boost situations. If you stand behind my car at an idle, it actually sounds like there are cams in the car. The fumes will make your eyes water. Can I recommend this to others? Not really. It's a crutch to get you by until larger injectors are in the budget though.

If you tuned the car right, it would not have a single one of those problems.

 

[kpt4321]

On the original topic:

If you need to bump the pressure, go ahead. However, larger injectors are always a better choice. Keep in mind that the higher your fuel pressure is, the less the pump will be capable of flowing. If you go too high, then you'll end up losing fuel flow.

You also don't want the fuel pressure too far above 80 psi under boost.

 

[NJdsmguru]

I know that about fuel pressure being over 80 psi. That's why i'm going keep boost under 22 psi on c16 race gas until i have enough money for 680cc injectors.

 

[smokinstorm]

If you tuned the car right, it would not have a single one of those problems.

If I had any device with which to tune the car, it probably would be tuned right. Unfortunately for me, I ran out of money before I could afford the AEM and larger injectors. It's coming though.

 

[FASTSPOOLINGST]

I have PTE 680cc injectors w/ FMIC, 255 pump, Aeromotive AFPR, and blowthrough set up. I am running my ext. wg at 17 psi. I also have the MAFT new version..no afc. My base is set properly (high trim 99.5-100.7%) and my O2's cycle right at around 100% when cruising, but no matter what, i can't get the idle good. My car runs perfect while driving, but at idle is a different story. I did leak checks, fixed the two that I had, but it still does it. A friend suggested raising the fuel pressure with my set up.

Before, I was set at 38psi with line disconnected. The car would go off the chart lean at idle and eventually die. I raised it to 41psi with line disconnected and it idled a bit better and didn't die, but still choppy and lean. I was worried about turning it up anymore, i am scared i will damage my injectors.

What do you guys think about my set up and what is a common setting for the 1g's with similar set ups. Any info is welcomed.

Thanks