80lb injector duty cycle on e85

Lstruck03

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Hey guys, I have been talking with alot of tuners lately and it seems the general consesus is that 80lb injectors will not support 700whp on e85 without a return style system. And from what I have been told, even with a return system, the duty cycles are in the mid 90's.

So, for those of you who have 80lb injectors and are making good power (close to or over 700) post up your combo (blower size, boost amount, fuel system) along with your tuner and your injector duty cycles.
 
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vladSVT

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2.8H Kenne Bell (20psi on gauge) 3.25 upper and 2lb lower.

80lb FRRP injectors, ford gt pumps, 8an line, 40amp bap @ 40, dual fpdm, returnless fuel system, i made 694rwhp, my pumps are close to maxing but my injectors have plenty of room (not plenty but they are in the mid 80s if I recall corectly)

I am pretty sure if your fuel system is up to par (unlike mine) your 80s should support around 750rwhp pretty easily
 

HotStart

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Hey guys, I have been talking with alot of tuners lately and it seems the general consesus is that 80lb injectors will not support 700whp on e85 without a return style system. And from what I have been told, even with a return system, the duty cycles are in the mid 90's.

So, for those of you who have 80lb injectors and are making good power (close to or over 700) post up your combo (blower size, boost amount, fuel system) along with your tuner and your injector duty cycles.


As long as they flow identically, a return system won't support anymore than a returnless one. What you do need to know is what delta pressure and A/F ratio they are running. An injector that flows 80lb/hr at a deltaP of 43.5psi will flow almost 94lbs/hr at a DeltaP of 60psi. Also, if two engines both make 700hp, but one is at an A/F ratio of 7.9/1, and the other is 7.2/1, the leaner of the two will obviously need less injector capacity than the engine operating at 7.2/1 A/F ratio.
 

sn94cobra

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my 80's are on the edge with return setup.

I have 80's, twin walbro pumps, -8 feed, -6 return, fore rails, fore F2 reg with 60 psi base pressure, BAP, wire upgrade.

With this setup on E85 with 2.3 whipple and 2.75 pulley, I made 658 on 23 degrees. My injectors are in the high 80's till 6K rpm than starting going into the 90's.
 

Lstruck03

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^ thats what I was thinking.

I plan on the new fore rails and the bosch 105's for my all out e85 tune.
 

mustangcobra98

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105s sound like a good option for you guys wonder if i could get away with them too? but I'm wondering how far i should go with my fuel system. I just bought a 2.6L over in the market place and and wanting to go with corn since i'm going to have to upgrade my fuel system anyway. I've already got an N2O system on the car. thinking around a 75-100 shot possibly. right now i've got 60pounders, obviously got to go bigger no matter what i do, 40 amp BAP, dual gt pumps and stock lines and rails.
 

USACHMP

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i cant say enough, if youre gonna upgrade the fuel system go return style. you could run those pumps still and go with atleast 80s.
 

LTHL VNM

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Fore Returnless system with Mega Driver Module
Triple pump hat
3 Ford GT pumps
-8 Fragola lines
rails
80lb injectors

22-23psi and i'm not even at 80% for pumps or injectors
i don't even get into the 90's on spray
 

cbr repsol

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i was told by tuner 80's were not enough. Ive seen many do it but it seems some people are having trouble. Im going return with twin 400's, bigger blower 2.9 or 3.4, and 21-23 psi. I was hoping for at least 700rwhp for now. Should i just get the 105's and call it a day?
 

04sleeper

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i was told by tuner 80's were not enough. Ive seen many do it but it seems some people are having trouble. Im going return with twin 400's, bigger blower 2.9 or 3.4, and 21-23 psi. I was hoping for at least 700rwhp for now. Should i just get the 105's and call it a day?
It all depends on how much pump you have feeding them.

There's more to it than "Are 80's enough?"

I would say with the twin 400's, the 80's will be plenty.
 

GodStang

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If you are looking for more than 700rwhp than going Return style is the way to go. I learn that after spending $2K on MDM and Fore triple hat and pumps then about 200 miles later I switched out to the Return style system.

As far as power you can get with 80s depends on pumps feeding it and how good your tuner is. Everyone feels that the tuner they go to is great because their light modded car is drivable. That is far from what makes a good tuner. There is maybe and I repeat maybe 5 great tuners for our cars world wide. The rest can get you there with canned tunes that they claim are theirs and they switch from car to car and set you to go. You find one of the true tuners and the 80s will be enough to get you into the 700s. On a return system into the 900s.

On a return system 80s have made 800rwhp on E85 many times and 80s have made 900rwhp on E85 before. So are 80s more than enough yes without a doubt. Can your tuner tune a car to do it. Most likely not.

This was learned from tons of money spent and trips to shops with nothing fixed.
 

cbr repsol

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Sorry I should of specified I was going return with 400 pumps. There was so much talk about return ,I thought everyone was talking return set ups.

@godstang where can I get my car tuned really well on e85? I advised tuner about 80s would be enough as many have done it here and he dissagreed with me so I think u are right about finding someone who can really do it properly. Any help would be great.
 

04sleeper

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With the return fuel system you just set your base fuel pressure at 50 psi (with vacuum off) and tune the 80's normally. It's in a returnless system that you have to raise the fuel pressure in the tune.

I have tuned several car with 80's and all of them drove like stock.
 

sn94cobra

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With the return fuel system you just set your base fuel pressure at 50 psi (with vacuum off) and tune the 80's normally. It's in a returnless system that you have to raise the fuel pressure in the tune.

I have tuned several car with 80's and all of them drove like stock.

I agree, My 80's drive perfect.
I have my base fp set at 60
 

Lstruck03

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It all depends on how much pump you have feeding them.

There's more to it than "Are 80's enough?"

I would say with the twin 400's, the 80's will be plenty.


If that's the case, then 3 gt pumps should be plenty as well.

I really need to get my e85 tune done.. I'm gonna go broke between race gas and o2/widenand sensors.
 

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