anyone here do e85

[RALPHIE]

Basic physics - if you increase the output flow, you will drop the pressure, all other things being equal.

 

[jcthorne]

All other things are not equal. There is a pressure control element in the loop. Injection pressure remains at setpoint unless the capacity of the system is over run.

 

[B.M.F.]

it is my understanding that the stock fuel pumps in a GT are rated to flow 255 LPH each. can anybody verify this for me? the fuel pump that i just put into my 2001 Camaro SS is a 255 LPH pump. this pump is designed to support up to 600 rwhp and 700 rwhp with a boost-a-pump....

so that means in a Ford GT application it should support up to 1200 rwhp without boost-a-pumps and 1400 rwhp with boost-a-pumps.

i think the problem with the GT is not the pumps but the returnless style fuel system. when you put bigger injectors in, the fuel lines get maxed out according to my local mechanic. he says the fuel rails can handle it but the fuel lines can't. apparently at some point the fuel lines go into a 2 into 1 configuration between the gas tank and the fuel rails. this is the bottleneck according to him. can anybody tell me where this takes place? does this happen right after the lines come out of the tank or just before the fuel rails? i would think that this would take place right before or after the fuel pressure regulator? before the fuel rails would make no sense because they would have to split apart again to feed each of the two rails.

sorry but there is no way a single 255 pump will support that type of power and esp on e85. The Gt fuel system will NOT Support more than 700rwhp on e85 PERIOD THEE END. IF the GT system will only support a supercharged gas motor with boost a pumps to 1000rwhp MAX, just do some simple math and devide 30% from that and that's what its good for on Korn.

For instance the guys running the GT500s are using 3 465lph pumps to make 1200whp..You can not have enough fuel system with e85, if you think you have enough you probably don't.

I tried both factory pumps, a return style system and a 3rd big pump Magnafuel efi pump (supports 800rwhp on e85) and I ran out of pump at 1400rwhp. Then I put a boost a pump on that magnafuel pump alone and made my duty cycle go down (77%) and I was running 58 lbs of base and close to 100 with boost. Then I put a belt pump on it and with the regulator set the same, the injecotor duty cycle went down to 54% due to the volume of the pump compared to 3 electric pumps. You cant always look at pressure and think your ok.

ALso in cars with gas tanks in the rear and pushing fuel to the front you lose volume when the car is moving due to the weight of the fuel in the line and the distance it travels.

Ive been playing with e85 longer than a lot of people and no most of the ins and out of it.

hope some of this helps.

 

[Fast Freddy]

sorry but there is no way a single 255 pump will support that type of power and esp on e85. The Gt fuel system will NOT Support more than 700rwhp on e85 PERIOD THEE END. IF the GT system will only support a supercharged gas motor with boost a pumps to 1000rwhp MAX, just do some simple math and devide 30% from that and that's what its good for on Korn.

For instance the guys running the GT500s are using 3 465lph pumps to make 1200whp..You can not have enough fuel system with e85, if you think you have enough you probably don't.

I tried both factory pumps, a return style system and a 3rd big pump Magnafuel efi pump (supports 800rwhp on e85) and I ran out of pump at 1400rwhp. Then I put a boost a pump on that magnafuel pump alone and made my duty cycle go down (77%) and I was running 58 lbs of base and close to 100 with boost. Then I put a belt pump on it and with the regulator set the same, the injecotor duty cycle went down to 54% due to the volume of the pump compared to 3 electric pumps. You cant always look at pressure and think your ok.

ALso in cars with gas tanks in the rear and pushing fuel to the front you lose volume when the car is moving due to the weight of the fuel in the line and the distance it travels.

Ive been playing with e85 longer than a lot of people and no most of the ins and out of it.

hope some of this helps.

well then you need to tell that to Greg-TT on this site and not me :thumbsup because he told me to my face at Mojave that his 3.4L Whipplecharged GT made 851 rwhp on E85 with the stock fuel pumps on a dynojet....

thanks for playin sir, but you did not answer either one of my two questions in my post....

 

[Fast Freddy]

Basic physics - if you increase the output flow, you will drop the pressure, all other things being equal.

i assume you are referring to the output flow of the Bigger injectors here and not the output flow of Bigger than stock fuel pumps?

based on this intel one would need to raise the fuel pressure then.

 

[Fast Freddy]

All other things are not equal. There is a pressure control element in the loop. Injection pressure remains at setpoint unless the capacity of the system is over run.

assuming the pumps are not maxed out then what i understand you to say here is that either the onboard computer will adjust the fuel pressure regulator or the fuel pressure regulator itself will adjust to compensate for the Bigger injectors? if this is not sufficient then one would need to set the fuel pressure higher manually or by means of the computer than the stock 58 PSI? i wonder if 58 PSI is sufficent for Bigger injectors?

 

[B.M.F.]

assuming the pumps are not maxed out then what i understand you to say here is that either the onboard computer will adjust the fuel pressure regulator or the fuel pressure regulator itself will adjust to compensate for the Bigger injectors? if this is not sufficient then one would need to set the fuel pressure higher manually or by means of the computer than the stock 58 PSI? i wonder if 58 PSI is sufficent for Bigger injectors?

the more pressure you run the less volume you get from the pump and most injectors are based off a 43lb base so you can run less than 58lbs on any injectors and most oe base fuel pressure is below 40lbs.. That's a lot of power out of a 3.4 whipple...Stock motor? wonder what his inj duty cycle is??? Maybe he can chime in.

 

[BlackICE]

hint √2

 

[peiserg]

this would be for my daily driven fgt. not for occasional use. if that's the case, i can just stick with ms109

 

[jcthorne]

assuming the pumps are not maxed out then what i understand you to say here is that either the onboard computer will adjust the fuel pressure regulator or the fuel pressure regulator itself will adjust to compensate for the Bigger injectors? if this is not sufficient then one would need to set the fuel pressure higher manually or by means of the computer than the stock 58 PSI? i wonder if 58 PSI is sufficent for Bigger injectors?

There is no mechanical fuel pressure regulator in the stock system. The pumps are electronically modulated by the computer to maintain a programmed pressure. As long as the pumps do not max out, there is no compensation, the fuel pressure remains the same in the fuel rails where it is measured regardless of size of injector. Once the injectors flow more than the pumps and lines support (the pumps are at 100%) the pressure drops off as the system is now outside the control range. Hope that helps.

 

[Fast Freddy]

the more pressure you run the less volume you get from the pump and most injectors are based off a 43lb base so you can run less than 58lbs on any injectors and most oe base fuel pressure is below 40lbs.. That's a lot of power out of a 3.4 whipple...Stock motor? wonder what his inj duty cycle is??? Maybe he can chime in.

he said his long block was completely stock. he had drilled holes in his airbox and was running a 3.0" pulley. i can't remember what his exhaust mods were though....

 

[Fast Freddy]

this would be for my daily driven fgt. not for occasional use. if that's the case, i can just stick with ms109

i would never run E85 in my GT full time. i would just have a tune to use at the track for it only....

 

[Fast Freddy]

There is no mechanical fuel pressure regulator in the stock system. The pumps are electronically modulated by the computer to maintain a programmed pressure. As long as the pumps do not max out, there is no compensation, the fuel pressure remains the same in the fuel rails where it is measured regardless of size of injector. Once the injectors flow more than the pumps and lines support (the pumps are at 100%) the pressure drops off as the system is now outside the control range. Hope that helps.

ok now we are getting somewhere. thanks for the help JC :cheers sorry for all of the drama guys but some of us just don't have the money or the time to take a chance of burning our motors up due to incorrect data :willy

 

[tmcphail]

That is why you put the right people in place that have a firm grasp of the control system so you don't have to.

 

[B.M.F.]

That is why you put the right people in place that have a firm grasp of the control system so you don't have to.

This^ it's not rocket science to run e85. There are tons and tons of oe cars out there that run it that are not flex fuel vehicles.

Torrie have you done many e85 cars?

 

[Fast Freddy]

That is why you put the right people in place that have a firm grasp of the control system so you don't have to.

Thanks for tuning my GT Torrie :thumbsup

i have done some research on the 255L pumps that reside in our GT's and here is what i found out. at 58 PSI the flow rate is less than at 43.5 PSI. also the flow rate for a NA engine like my '01 Camaro SS has is Higher than in a Boosted motor like our GT's have. this is why i can run a single 255L Walboro pump to feed my 600 HP 402 CI LS2 stroker motor because not only does it not have forced induction but it operates at a lower fuel pressure which increases flow. that being the case i would assume that my GT is tuned by you to operate at 58 PSI? and will not function properly at 43.5 PSI because it is a boosted motor? i was just curious because the flow rate of our pumps goes up when utilizing a lower fuel pressure. either way i would not attempt to run E85 in my GT without Bigger fuel pumps based on the intel i have sourced on the net here....

http://radiumauto.com/media/techarticle-page.php?Radium-s-Ultimate-Fuel-Pump-Test-87

 

[Thugboat]

Sheeesh! Lets bring back the Holley HP750 Double pumper and be done with all this! Y'all are making my head hurt! haha

Larry

 

[tmcphail]

Thanks for tuning my GT Torrie :thumbsup

i have done some research on the 255L pumps that reside in our GT's and here is what i found out. at 58 PSI the flow rate is less than at 43.5 PSI. also the flow rate for a NA engine like my '01 Camaro SS has is Higher than in a Boosted motor like our GT's have. this is why i can run a single 255L Walboro pump to feed my 600 HP 402 CI LS2 stroker motor because not only does it not have forced induction but it operates at a lower fuel pressure which increases flow. that being the case i would assume that my GT is tuned by you to operate at 58 PSI? and will not function properly at 43.5 PSI because it is a boosted motor? i was just curious because the flow rate of our pumps goes up when utilizing a lower fuel pressure. either way i would not attempt to run E85 in my GT without Bigger fuel pumps based on the intel i have sourced on the net here....

http://radiumauto.com/media/techarticle-page.php?Radium-s-Ultimate-Fuel-Pump-Test-87

View attachment 31675

Your car from the factory and within its current state works to target a commanded 39psi desired pressure drop across the injectors. The only reason why someone would want to increase this is to essentially make the injector larger then it is at the expense of fuel pump DC

 

[Fast Freddy]

Sheeesh! Lets bring back the Holley HP750 Double pumper and be done with all this! Y'all are making my head hurt! haha

Larry

Larry - I have reached the point with my GT where if I want more power either i put Bigger fuel pumps in or I go Twin Turbo. Unless I can find a way to add one or two more fuel pumps externally outside of the gas tank to boost the stock fuel pumps. I am not sure if this can be done though and how one would plumb everything to properly interface with the stock fuel pumps? If somebody knows I would be interested....

 

[tmcphail]

Larry - I have reached the point with my GT where if I want more power either i put Bigger fuel pumps in or I go Twin Turbo. Unless I can find a way to add one or two more fuel pumps externally outside of the gas tank to boost the stock fuel pumps. I am not sure if this can be done though and how one would plumb everything to properly interface with the stock fuel pumps? If somebody knows I would be interested....

Soroush has a neato setup that uses 2 external pumps and a reservoir. It's a pretty cool system and I am fluent in how to make it work calibration wise.