I need to figure out exactly what size injectors to get. I will be running E-85 with a power goal of 350 HP and later around 500 HP.

I found looked at an injector sizing chart and it said 713cc would be 495 HP. Would 720cc suffice for 500 hp?

Do I have to use 1000cc since I am running E85?

 

1600cc for e85 and 500whp

 

To elaborate on this the Injector sizing is for the SAME HP with E85 you need almost 1.5x the Fuel Injector sizing.

But for 500WHP I'd say estimate .77lb-hr BSFC(anecdotal from another E85 turbo car), 80% Injector Duty, stock fuel pressure. I'd say 1500CC is the exact number so really this is just an explanatory for DreaMsteR's number.

 

For E85, you actually need about 1.3x more injector than for gasoline. Using a simple equation where 6cc supports 1whp, you can get a rough idea of your injector needs.

500whp x 6cc (per whp) x 1.3 (e85 conversion factor) = 3900 cc total
3900 cc / 4 inj = 975 cc injectors

Given that number, i would go with something 1200cc or larger. Hope that helps

 

i run rc 1000's man im at 98% duty@600hp we turned it down so we werent that close, but on a a1000 fuel pump we were out of pressusre from it or close to e85 is awsome it just requires a little bit more than gas lol. oh that was at 29psi on the turbo as well.

 

Yes I did mess up on my number there. I'd just used to giving the stoich conversion number and forgot we were talking about a turbo car to get a certain WHP. But for tuning where you don't know the max HP you can go 1.5x or 2x the cc than you would for a certain WHP of gasoline? If you go from C16 to E85 you can use the 1.5x the same CC since the HP will probably be close. But going from Pump gas to E85 you'll never know how much more you can get.

Sanman is that WHP or BHP because you're just confuzzling me. 600hp could be 500WHP and therefore 600BHP but I can't tell for sure.

 

^^It could be whp but at a higher base fuel pressure. The general equation i used above is for stock fuel pressure. If one was to bump it up, you could make another couple ponies with the same injectors. Honestly, I run 1000s in my daily and they're fine. If you're looking to make more power than my setup, i would highly recommend a larger set of injectors just to be on the safe side. They'll idle fine if your tuner knows what he's doing...

 

Why not just get a conversion kit i did this to my civic, no injector change and i still have the same horse power, but also im only running an cold air intake, header, 2.5 inch pipe and itr muffler, so im not sure if it will work for your application but i thought i would share

http://www.youtube.com/watch?v=iXajLGqafyk ...... here is a link, i hope it works

 

we arent talking about just running e85 now and then he is more than likely talking e85 all the time this is ez a tune is what is needed, and the base pressure will need to be higher for e85 than for gas so more fuel pump is needed tony from t1 actually had an aswsome chart to show the differance from injector to pump to base pressure from gas to e85

 

^^You dont need to bump the fuel pressure up to run E85, but it does allow you to run smaller injectors for the same power goal. I'm running the stock FPR and still at base fuel pressure on my setup.

Also, those Injector Dynamic fuel injectors are pretty crazy. They flow more than a typical injector from what i've seen...

 

correct but my rc 1000's dont lol, and i have been told many times over that i need more fuel pump on e85 since its 85% alcohal not gas meaning more base pressure im thinking tony even told me that in the thread i pulled that chart from

 

nice info sanman!

 

Sanman, you and i are saying practically the same thing. Most likely, the reason Tony told you to bump the pressure was due to you already having injectors which were too small for your power goals. I'm running PTE1000cc injectors on my setup and dont plan to make any more than about 450whp on them ever. Bumping the base fuel pressure gives your injectors more flow

 

gotcha man


and your welcome noob

 

WOW! Thanks for all the good replies guys. This thread helped me a ton. Anyone use Precision Injectors? I seen some 1200CC on ebay for like $300! I think that's what I may go with . . .

 

I'm running Precision injectors; however, when people refer to them, you'll often see it as PTE (Precision Turbo and Engine) as in post #13 above. By the way, i would stay away from Ebay and rather check out the HondaMarketplace. You'll generally find better deals there AND you're supporting the businesses that keep this site afloat]

www.hondamarketplace.com <---Check the Forced Induction section (both sponsors and Classifieds)

 

well my ef was under the knife this week,and is ready for tune time tonight went from the log mani to a top mount and pt67 so hopefully my lil 1000's will do me proud on e85 lol

 

Goodluck!

 

kool thanx man

 

For sure. I have bought parts here and got amazing deals. I'm sure I will throw up a post when I am ready to buy my parts.