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-   -   fuel injecters and fuel pump? (https://www.rx7club.com/alternative-fuels-249/fuel-injecters-fuel-pump-1061896/)

sideways-FC 04-18-14 12:54 AM

fuel injecters and fuel pump?
 
im am going to be getting my FC tuned in the next few weeks and i need to know what size injecters to order. its a large street ported 13b on E85 with a BWS366 turbo and im aiming for like 400-500hp. would i be able to get away with 1800cc secondarys and 750cc primarys? and what am i going to have to do about my fuel pump? coz im only going to have enough money for one 255lph in tank fuel pump. will that at least support 400whp?

Rob XX 7 04-18-14 08:09 AM

I had 1680 and 850s, with a supra pump.
On pump fuel I believe that set up is good for 500hp in a rotary.

Now try to push E85 through it- now its good for 350hp.
I first tried swapping the pump for a 044 only to find out my injectors were now maxed out so swapped them too.

You will not have anywhere near enough fuel for 400hp let alone 500.

You need to seriously address your fuel system before you even aim for 400hp.
You cannot skimp on fuel you will go BOOM

Howard Coleman 04-18-14 09:30 AM

"i am going to be getting my FC tuned in the next few weeks and i need to know what size injectoers to order. its a large street ported 13b on E85 with a BWS366 turbo and im aiming for like 400-500hp. would i be able to get away with 1800cc secondaries and 750cc primaries? and what am i going to have to do about my fuel pump? coz im only going to have enough money for one 255lph in tank fuel pump. will that at least support 400whp?"



rule number 1

fuel system needs to match MAXIMUM turbo power output. you don't bolt on a 575 rwhp turbo and have fuel for 400 hp.

wastegate sticks closed
engine goes boom

your S366 can make 550, maybe a touch more.

550 X 1.92 = 1056 CFM / 14.471 = 73 POUNDS of air

you need to be able to tune to 10.5 AFR to be on the safe side so

you need 6.95 pounds of gasoline

6.95 / 6.35 = 1.09 Gallons Per Minute of gasoline net into the engine.

1.06 GPM is 4126 CC per minute. that's for gas.

adjusting for E85 (82,300 BTUs per gallon V gas at 116,090)

4126 X 1.41 = 5818 CC per minute NET

adjusting for lag and 85% max duty cycle:

5818 X 1.35 = 7854 CC per minute Gross

you need injectors rated for 7854 CC Minimum.

anything less and you will blow your motor w a stuck wastegate.

you need a pump that will do 5818 CC per minute at 25 psi boost.

5818 is 349 liters per hour at 25 psi.

the Walbro E85 pump PN 9000267 will do 93 gallons per hour at 70 psi/13.5V which is
5867 CC/Minute. it is a drop in and not particularly expensive.

it will be essential that you hardwire the pump, use a 30 A fuse and suitable relay.

good luck,

howard

sideways-FC 04-18-14 10:14 AM

so i geuss i will have to go with 2000cc secondarys then. what will i have 2 go with for my primarys will 750cc injecters be enough? and where can i get that fuel pump for e85 u where talking about? would i be able 2 find it on summit?

1NSIGHT 04-18-14 11:08 AM

Pump

At the 550 hypothetical HP Coleman posted you'll need 7900cc of injector.

If you go for 450ish you could just run your 1800cc as primaries and hope they'll be able to run at idle dwell times(like the ev14s can) and get 2000cc for secondaries. That would be less expensive than getting (4) 2000cc injectors and would probably run ok at low speeds.

Im sure somebody will correct me if Im off.

sideways-FC 04-18-14 11:35 PM

1800cc PRIMARYS!!!??? that cant be right?

Rob XX 7 04-19-14 08:11 AM

I run 2000's as primaries and my 850s as secondaries
the 2000s are EV14 they are very stable even when im on my 93 tune

sideways-FC 04-19-14 08:36 AM

so i would be good with 850cc primarys? and why would you run bigger primarys and smaller secondarys?

Rob XX 7 04-19-14 08:54 AM

we felt it would be smoother overall, less transition during regular driving

1NSIGHT 04-19-14 10:05 AM

How did you stage smaller secondaries? what ECU?

I wnat to use my 1000cc ID as primaries and 550cc stock as secondaries

vrx8 04-19-14 10:43 AM

A quick fix if you don't know how to tune transition lol

vrx8 04-19-14 10:52 AM

OP you need at least 1700 pri and 2000 sec. and more fuel pump (Walbro e85 pump for intank or dual 044 external)

sideways-FC 04-19-14 12:26 PM

so at least 1700cc primarys and 2000cc secondarys! holey shit i think im about 2 be broke!

Rob XX 7 04-19-14 12:45 PM


Originally Posted by vrx8 (Post 11721426)
A quick fix if you don't know how to tune transition lol

thanks for your input, im sure my tuner knows how to tune for transition.
I planned the injector sizes from the start that way, it was partially my idea its not like we couldn't tune the car and said "ah fuck it lets swap them around"
The way my car drives is more important to me than WOT, anyone can tune WOT having a car you can drive in traffic without aggravation is key

ECU is a Wolf V500

original poster- why not go for 4x2000's

vrx8 04-19-14 01:11 PM


Originally Posted by sideways-FC (Post 11721474)
so at least 1700cc primarys and 2000cc secondarys! holey shit i think im about 2 be broke!

Lol, it will cost less than a repair for a blown engine. I personally use 4x2000 and made 460@18psi whp. ID injectors primaries idles like a dream at .95 MS.

sideways-FC 04-19-14 01:56 PM


Originally Posted by vrx8 (Post 11721487)
Lol, it will cost less than a repair for a blown engine. I personally use 4x2000 and made 460@18psi whp. ID injectors primaries idles like a dream at .95 MS.

yea i know. what ecu where u running?

vrx8 04-19-14 04:04 PM

Haltech 1000

sideways-FC 04-20-14 03:31 AM

im running a sprint re. hopfully i can get it to start and run decent on the new injecters and everything be for i take it to get tuned.

zachvirus 01-26-15 11:14 PM

i'm looking to run either x4 2000cc or 2150cc primary and secondary injectors, would that Walbro E85 par alone or would an external pump be neccesary still, same goes if i went dual bosch 044 external, etc etc


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