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-   -   How much whp w my injectors (https://www.rx7club.com/alternative-fuels-249/how-much-whp-w-my-injectors-1036240/)

ChrisRX8PR 05-25-13 01:31 PM

How much whp w my injectors
 
Deciding between

1000cc pri + 1680 + 720 2ndaries.

Or

1000 pri + 1680 + 2000 2ndaries

I'm not looking for more than 600whp. I have enough turbo and fuel system etc.

Thanks.

Chris

RXTASY57 05-25-13 01:42 PM

Can you run 6 injectors? If you can, you have enough injector.

ChrisRX8PR 05-25-13 02:34 PM

Yes i have six installed now...like the first option i posted.

Thoughts?

Thanks.

Chris

BLACK MAMBA 05-25-13 02:49 PM

6 1000cc should do it, if going with E85 4 1000 and 2 2000

ChrisRX8PR 05-26-13 01:18 PM


Originally Posted by FC3S1991 (Post 11477511)
6 1000cc should do it, if going with E85 4 1000 and 2 2000

I dont have 6 1000cc injectors. I have the first comination of 6 injectors i posted. I want to know if that combination is enough for up to 600whp or if i will have to swap the 720s for 2000s. Does anyone know the math for a rotary on e85?

Thanks

Chris

RXTASY57 05-26-13 01:35 PM

You can get 600 RWHP on the injectors you have if you run gas.
You would need a little more to run E85.
I am running 4X2000 ID injectors and I run out of fuel on E85 around 30 PSI which is somewhere between 600 and 700 RWHP.
E85, you just add 30% more fuel to everything.

Howard Coleman 05-26-13 08:33 PM

"Does anyone know the math for a rotary on e85?"

it takes 145,537 BTUs to make 600 at 10.0 to one AFR

E85 contains 80,767 BTUs per gallon (assumes 83% eth, 15% gas, 2% filler)

you need 9200 CC/min of E85 nominal (gross) to get 6800 CC/Min into the engine to make 600.

9200 X .85 (max inj duty cycle) X .87 (lag) = 6800

this capacity allows you to run 10.0 to 1

you can make 600 w a bit less if you run leaner than 10 AFR or raise your rail pressure. it is good to be able to tune rich if you need and also to have some reserve for pressure loss.

howard

RXTASY57 05-26-13 08:40 PM

10:1 is too rich with E85.... Make more power at 12:1 and no detonation whatsoever.

ChrisRX8PR 05-26-13 10:38 PM

Thanks Howard/RXTASY. I decided to use the 2000cc injectors instead of the 720cc. As it sits now I have 1000cc primaries, and 1680+2000cc 2ndaries per rotor or 9360cc of total injection for the engine. Its probably safe to assume that I will not need another upgrade, ever...lol

Cheers!

Chris

Howard Coleman 05-27-13 08:22 AM

"10:1 is too rich with E85...."

i agree. i think it is wise to build in some over-capacity as to fuel and therefore picked 10.0 to do that.

howard

elturbonitroso 05-27-13 05:41 PM

how much h.p will 7200cc of injection would make.thanks

BLACK MAMBA 06-07-13 08:42 PM

There's a guy here in the forum that dyno 689hp with 2 850 primaries and 2 1600 secondaries on E85, just raise the fuel pressure like he did

BLACK MAMBA 06-07-13 08:44 PM

I have 2 1000 and 2 2000 and looking to switch or maybe mix 50/50 with 93, what you think this combo is capable off running dual stealth 340 pumps?

audoetuk 06-22-13 08:58 PM


Originally Posted by FC3S1991 (Post 11489467)
There's a guy here in the forum that dyno 689hp with 2 850 primaries and 2 1600 secondaries on E85, just raise the fuel pressure like he did

Hmm. REW?

sleeper7 06-23-13 06:54 PM

running two 1600s for primary, four 1600s secondary with two 1000s secondary. Fuel pressure above 45psi key on engine off.

9000 rpms = 6 ms under full load. 11.5 afr. No power difference from low 11s afr to high 11s afr

151mph in the 1/4 mile, 2650lbs with me. No dyno numbers

Just to give you a idea.

recently replaced the 1000s with 1800s. Now the power can be turned up. :nod:

Everyone talks about 30% more fuel is needed when going E85. seeing more in the 35/40% range.

RX-713B 06-23-13 08:32 PM

Call me a dummy but how can one raise the fuel pressure? I've never done that.

RX-713B 06-23-13 10:27 PM

And maybe someone can help me dial in the right fp.

vrx8 06-24-13 08:16 PM

^^ What? do you have a fuel pressure regulator?

BLACK MAMBA 06-24-13 08:21 PM

1000/2000 injectors here, just raise my base fuel pressure to 60psi and I'm seeing 10.2afr at 25 psi, will pull some fuel out and raise boost to 28 psi.

Once that's done will re dyno the car to compare to my 28psi 590hp tune in gas

RXTASY57 06-25-13 07:56 AM


Originally Posted by RX-713B (Post 11503047)
Call me a dummy but how can one raise the fuel pressure? I've never done that.

Should be a post on top of the FPR with a nut on it.
Take the vaccum line off the FPR and start yer car. Adjust the nut in or out until you get the desired base fuel pressure, then put the line back on and tighten the nut. Yer done!


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