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Limits of stock fuel pump?

Posted: Fri Feb 28, 2003 4:49 pm
by 91White-T
I remember someone saying in another post that it's good for 15-16psi, just wanted a few more opinions before I try that...

Posted: Fri Feb 28, 2003 5:05 pm
by boostjunkie
Looks like another boostjunkie's in the making . . .

NEED MORE BOOST!!! :twisted: :twisted:

Posted: Fri Feb 28, 2003 6:05 pm
by 91White-T
11psi just isn't enough anymore... :D

Posted: Fri Feb 28, 2003 7:42 pm
by boostjunkie
I know what you mean . . . 16.9psi is starting to bore me :twisted:

I thought milehi would have some input on this since he's worked on a turbolegacy and I thought he tested the limits of the stock fuel pump.

Posted: Sat Mar 01, 2003 4:32 am
by mile hi
I'm here, I think that the limits of the stock pump is probably around 250 crank hp we were running 318 at the crank and were being limited by the fuel pump. The pressure started to fall very fast at WOT near redline. this was with stock injectors. Seeing the results leaning out can possibly bring I would get a 255lt per hr pump.
AL(CO)
al@iwtu.net

Posted: Sat Mar 01, 2003 9:34 am
by -K-
It's never "enough" boost..... more I want more....

Posted: Sat Mar 01, 2003 1:00 pm
by LegacyT
Yeah thats what my father said. The stock pump is good for many more ponies than what the motor runs stock. This case being roughly ~80-100hp. But ya, If you have power hungry dreams go for a Walbro 225lph or the like.

Mark,

Posted: Sat Mar 01, 2003 4:28 pm
by 91White-T
Ok, so what would be a safe amount of boost to run?

Posted: Sat Mar 01, 2003 6:43 pm
by mile hi
You have an intercooler and if it's an air to water like mine (Liberty) I would say 14-15 and 20 for short bursts that is what I do but I would watch for lean out at the top end. Our 500 hp Impreza is running a stock EJ22t Block and is running 30 lbs with all out mods including a large amount of fuel. To me this and the fact that we have not seen a large amount of EJ22t failures means that the basic block is pretty strong.
AL(CO)
al@iwtu .net

Posted: Sat Mar 01, 2003 6:53 pm
by LegacyT
Are you sure you can "lean out" a fuel injected engine? On a carbed motor I can see it happening, but on an engine with an ECU, will it allow the engine to run lean? 91White-T, the Stock fuel pump is even better than a stock WRX pump. So it's good for maxing out the stock turbo (16 psi). And good for roughly 250hp.

Mark,

Posted: Sun Mar 02, 2003 6:51 am
by mile hi
It is possible it's just that they can not deliver enough volume to keep the pressure up and when the pressure falls I would imagine that the spray pattern would be the first thing to suffer and then the amount would have to drop. I noticed a difference in My Impreza\ turbo legacy with the 255 lph pump as it had a pump for a EJ18 in it when I got the car. I also noticed it at the strip with my XT loyale with a EJ22 engine that was turning 8500 rpm.
AL(CO)
al@iwtu.net