I am sure there is some formula for #'s an hour but I don't know it. They are going to a tad over 100% duty cycle now that my car is making some power. I am not sure if it is the injectors or the aeromotive eliminator pump that is maxed out. The car is making close to 800 rwhp right now. The pump is listed to handel 1,150 I believe at the crank but that really means nothing. I also have it on 16 volts so it should be working overtime. I have some 160's to put on but I was just curious if this sounds like the injectors are done or the pump. Thanks for any help!

 

a buddy of mine maxed out a brand new eliminator with 620rwhp on a blown cobra..

-42lb injectors
-fmu 5:1 disc?
-8 feed
-6 return
-20psi

with the larger injectors you dont need as much fuel pressure as he did, but i'd say your pushing your luck with that pump.

 

sure that wasn't just a A1000 pump? The eliminator is supposed to be good to over 1000hp forced induction while the A1000 is around 650 rwhp typically.

 

he had an a1000 (used) at first and it went lean at 4200, so he bought the eliminator.

keep in mind he was running a VERY high fuel pressure with the fmu, so it was reducing the flow of the pump some.

 

I'm not qualified to answer the question regarding your combo, I just wanted to offer you these charts.

Take note there are 3 different tabs at the bottom with different information.

http://paradox.shacknet.nu/dave88lx/formula/383/injectors.htm

Well fuck, I just realized I only went up to 42#/hr injectors, sorry. Yes there's a fomula, quick google search will bring it up.

 

My 72lbers checked out @ ~950HP, running them at 45psi static on a 1:1 regulator.

 

ok ok,should have just got bigger injectors then? why did he want to keep the 42s?

 

he didnt believe me when i told him that the fmu was a band-aid for the smaller injectors, him and my 5 other buddies thought it was the only way to reference boost...needless to say they were ALL new to boost, and wouldnt listen.

IMHO-i wouldnt trust the a1000 or eliminator pump at 800rwhp, unless you have a disposable j/y motor (hes pushing at or near 900fwhp if the pumps rated at 1000fwhp any glitch in the system or voltage drop and BOOM) i think 100hp from the max is too close for me to handle.

 

I think you are right about trusting that pump. I have bigger injectors to put in but I was hopeing the pump would not need to be replaced. It would probably be wise to get a Weldon 2025 now I guess. Anyone need a Eliminator pump with only 37 pass's on it?

 

I agree with the A1000, but the Eliminator can/will support in excess of 800rwhp. My Eliminator has been in place for 3 years operating @ this power level and beyond.

 

I'm using the eliminator pump at 840 rwhp!!
No problems here either!!

 

So if you guy's are not having problems with that pump then I guess I can assume the injectors are maxing out??? The A/F is good even when the duty cycle is around 110% but I feel it will not be safe to add any more power untill I figure out why the duty cycle is so high. I guess I can just try the bigger injectors but they will not tell me if it is running out of pump since they will only be seeing like a 40-50% cycle. Like I said the pump is also seeing 17 volts going down the track so it should be pumping more fuel then at 13.5.

 

I am having the same problem, but I fear I do have too small of an injector. I have a weldon under the car and I know that isn't the problem. According to the f.a.s.t I am at 107% duty cycle and this is with 50lb injectors, A/f of 11:1 and 4psi of boost. I just bought some 83lb'ers so hopefully this will solve my problem. Hopefully.

 

A Fuel pressure gauge will tell you a lot...Pressure not falling...means pump is keeping up.

I run my 72's at 55 psi static (makes for a real good low end) Only pumped 10 lbs on top of the pistons..20 psi is right around the corner...Eliminator here also...really like the quality and quietness( for an inline) pump.

 

Your right about the fuel pressure guage.....unfortunatly I am not a skilled enough driver to look down at the guage during a 5 second run. The fuel pressure is set at 45 psi static though.

 

As rear wheel hp, I have seen almost 1000 on my buddies 16 lb liqiuid to air viper.Running an eliminator.

Truestreet, check it on a dyno run...may save a motor...could be clogged filter, collapsed line or stopped up/to small pickup in tank..Those big inline pumps need a big (as little restriction as possible) on the suction side.

I have plenty of time to check out all my gauges on my 5 second run...That also includes dropping the hammer(clutch) and pulling 3 gears...5.20 at 136mph...1.14 60'

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i assume weve established that the eliminator will support 850+rwhp

dont mean to hijack but...

do you think the extra 20-25lbs of fuel pressure would kill a pumps rating by 200rwhp? im just trying to figure out why it wouldnt keep up with the car i mentioned above, it was definitely the pump too, cause a weldon 2035 fixed the problem.

 

was looking at the flow sheet on aeromotives site and it looks like as pressure increases the pumps flow drops dramatically. if im looking at it right in my situation the 90lbs of fuel pressure needed put the pumps flow around 200lph. which i highly doubt would support 650rwhp

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Absolutely..

90lbs of rail pressure is the perfect catalyst for a system failure, the fuel pump doesn't matter much at this point, since the fuel injector's performance will suffer when subjected to very high system pressures.

 

slow 95, why would you put 90 psi on the pump anyway...an fmu...imo, a bad idea. You sure they are 72lb injector?