Tell me why I shouldnt get the 255lph...

[FourG63 97GST]

Originally posted by DCJ98GST



What are you saying that it is better to get the injectors first?

It seems like most people get the pump first?

yes, for the same reason. I prefer to run upgraded injectors on stock pump than ungrading the pump forcing the fuel through stock 450s.
So, Ill be going fuel management, then Injectors, then pump.

Discuss, I want to hear other opinions on that.

 

[Dieselboy]

Seems like a reasonable idea to me

 

[MaineDSM]

Originally posted by FourG63 97GST


yes, for the same reason. I prefer to run upgraded injectors on stock pump than ungrading the pump forcing the fuel through stock 450s.
So, Ill be going fuel management, then Injectors, then pump.

Discuss, I want to hear other opinions on that.

Hey, whatever works. But if your pump can't provide enough fuel with stock injectors, I don't see why it could provide more fuel with bigger injectors?

You have to upgrade whatever is the bottleneck.

I agree that fuel management is the best thing to get first. The equipment is useless unless you can control it. (That's what she said. )

 

[L2RTSiAWD]

I have a 255HP pump. It is not whiney what-so-ever.

It did overrun my FPR. Got a spoolinup with a 1G rail for about 150, problem solved.

 

[RockfordGST]

what about on a 2g
is a walbro 255lph to big with
big16
safc
550's

 

[JET]

You will need an AFPR. Get the Denso 190lph and you don't have to worry about it. If you have to get an AFPR anyway, you might as well get a supra tt pump.

 

[DCJ98GST]

I want to hear more opinions about wheather to upgrade the FP or the injectors first. Any other opinions?

 

[jayntguru]

I have always done:

pump, rewire, injectors.

Doesn't anyone search or use the tools anymore?

http://2g.dsm.org

Specifically, look at the "go faster" link.

 

[DCJ98GST]

Relax.

I know; that is what I thought, but If you were to take a second and read the posts above, people were recommending a different order.

 

[L2RTSiAWD]

Getting injectors first would make your idle suck with no afc becasue you would be dumping all sorts of extra fuel in.

 

[2GTsiAWD]

I am at that point now....I have the 255HP, but felt I should have gotten the 190 pump. Too late.. So now it was a matter of finding a regulator. Which I have now. The Aeromotive.

So now I can at least get the pressure back in line at get rid of the stumbling that I get.

As far as injectors are concerned....I'm going to look for an injector that's not going to require something else to keep them in check. It's ridiculous. Change this and you have to add that. Geez. Tuning a Grand National wasn't this hard. Hell you could run stock injectors until you were in the high 11's.

16G - Got it
Fuel Pump - Got it
AFPR - Got it
What's next???

Wonder if the injectors out of an Evo would work and not require a device to tune???

 

[G-Ell]

I don't recall if the typical 550's most people use are rated at 80% duty cycle or 100%, but if we assume 100% to stay on the pessimistic side (assuming that the pump and the injectors are both rated at the same pressure:

550cc/min per injector * 4 injectors = 2200cc/min (assuming you were
running the injectors wide open, which you're (hopefully) not).

190 liters per hour is 190,000 cc/hr, or 3166 cc/min.

Even after accounting for the pressure losses and all the fuel lines and what not, a 190lph (that's actually putting out 190lph) should be plenty for 550cc or 660cc injectors. Cutting it kind of close if you've got 720's.

 

[Eclipseturb1384]

Im going for the big 16g turbo and wondering if the walbro 255lph, aem fuel rail and the rc 550cc fuel injectors would be ok with this... would i run into any problems?

 

[doug]

Originally posted by MaineDSM
You have to upgrade whatever is the bottleneck.

Yeah, and the main bottleneck is the banjo bolt on top of the stock fuel filter and the filter itself. Get rid of those and you can run the stock pump easily.

 

[DCJ98GST]

According to this, 550's can support 325 hp at 85% duty cycle

hp = 325
# of cylinders = 4
duty cycle = 85
BSFC = .55


http://www.smokemup.com/auto_math/fuel_injector.php

 

[irn__man]

Originally posted by L2RTSiAWD
I have a 255HP pump. It is not whiney what-so-ever.

It did overrun my FPR. Got a spoolinup with a 1G rail for about 150, problem solved.

L2RTSiAWD ,


Did you do the Fuel Pump Re-wire Mod? I had no problems with my base fuel psi (43psi) with my 255HP pump, 1G fuel rail with CAS FPR, until I did the re-wire mod. Now I can't lower the fuel pressure below 46 psi.

If you did do the re-wire I have the exact same setup, what base Fuel Psi are you at?

thanks

 

[MaineDSM]

Originally posted by doug

Yeah, and the main bottleneck is the banjo bolt on top of the stock fuel filter and the filter itself. Get rid of those and you can run the stock pump easily.

Wrong answer. People run 500hp with the stock filter and banjo bolt. You may help out the stock fuel pump a bit by replacing those parts, but not enough to run a big turbo.

Do it right: Supra fuel pump, AFPR, big injectors.

 

[MaineDSM]

Originally posted by irn__man


L2RTSiAWD ,


Did you do the Fuel Pump Re-wire Mod? I had no problems with my base fuel psi (43psi) with my 255HP pump, 1G fuel rail with CAS FPR, until I did the re-wire mod. Now I can't lower the fuel pressure below 46 psi.

If you did do the re-wire I have the exact same setup, what base Fuel Psi are you at?

thanks

Thats because the 2G fuel return line is too small. You can just get some 3/16" line and run it from your AFPR to the return fitting on the tank. Problem solved.

I had to undo the rewire on my Supra pump because of the exact problem you are having.

I guess 1Gs don't have this problem, because their return line is slightly bigger. Damn 1Gs.

 

[irn__man]

Originally posted by MaineDSM


Thats because the 2G fuel return line is too small. You can just get some 3/16" line and run it from your AFPR to the return fitting on the tank. Problem solved.

I'll give it a try, but first I may just run some hose from the fpr to a gas can. To see if it is actually the return line.

Did you upgrade your fuel feed line to the fuel rail?

thanks for the help

iron

 

[Trctnless]

I run a Ported Big 28from FP with a Rewired stock Pump and stock injectors w a GM MAF, set 10% RICH MID?HIGH (Still no fuel cut) (technically the pump is unidentified as I think the previous owner may have upgraded it ) ((I'm getting a 190 anyway for peice of mind but only after I get 550''s))

Currently I run 93oct/ 16 psi w/ supra SMIC 1G TB and all other ICP upgrades. 3" exhaust /no cat. My datalogger and EGT's show me that its still ALL good and running rich. 1.04 @ WOT 19-21 deg ADV @ 6900 RPM Timing only gets pulled for a bit @ 4500 to like 11deg then advances nicley.

The car is primarily and autoX car... I'm aiming and expect mid 12's and don't plan on using an AFPR to get there..

 

[MaineDSM]

Originally posted by irn__man


I'll give it a try, but first I may just run some hose from the fpr to a gas can. To see if it is actually the return line.

Did you upgrade your fuel feed line to the fuel rail?

thanks for the help

iron

Me and a couple of other guys did exactly that. Ran a line to a fuel can to test it. That how we found out the 2G return fuel line is too small. Then I asked Buschur, and he confirmed it, and he also said that problem doesn't happen on 1Gs.

I did not upgrade the fuel feed line. I figured Bushur doesn't upgrade it on his 500hp cars, so why would I on my 300hp POS.

 

[irn__man]

Originally posted by MaineDSM


Me and a couple of other guys did exactly that. Ran a line to a fuel can to test it. That how we found out the 2G return fuel line is too small. Then I asked Buschur, and he confirmed it, and he also said that problem doesn't happen on 1Gs.

So, 3/16" fuel line is what you went with for your return line? For some reason 3/16" sounds a little small also. What size is the stock 2g DSM fuel return line.

thanks

 

[doug]

Originally posted by MaineDSM
Wrong answer. People run 500hp with the stock filter and banjo bolt. You may help out the stock fuel pump a bit by replacing those parts, but not enough to run a big turbo.

The SteveTek site seems to disagree. "SteveTek" himself has told me that even just replacing the stock filter and fuel line from there to the rail will give 90% of the benefits of replacing the entire fuel line from the tank to the rail with -6AN.

 

[MaineDSM]

Originally posted by doug

The SteveTek site seems to disagree. "SteveTek" himself has told me that even just replacing the stock filter and fuel line from there to the rail will give 90% of the benefits of replacing the entire fuel line from the tank to the rail with -6AN.

I honestly think that "SteveTek" site is a load of crap. After reading that site, you'd think a fuel pump upgrade would never be needed. Which is a load of hooey. Nothing about that site makes any sense.

 

[doug]

Maybe, I don't know. I'm not going to take anybody's word as gospel-- I'll try out different setups for myself and see what works. I am, however, curious to see how well a rewired stocker with the -6AN fuel line from filter to rail works. I've got the fuel line in, but just need to rewire the pump now.