Injector Size

[SXYSOL]

hey all got a question...

i'm planning on turboing my b16a in my delsol...i planning on running 6-8psi with new computer etc...

i'm wondering what size injectors are recommended on such a set up??

and does anyone know what size series 4 13B RX7 injectors are??

[Weq]

m pretty sure, around 440cc? just google.

[poid]

should be 440 or 550, rotary people will know.

440's and up should be fine. Larger sizes (within reason) will allow you to upgrade later without having to change them again

[WPN.22R]

i was advised not to use rotary injectors coz of their spray pattern. they dont actually spray, its more of a 'jet' straight spray.

have you already bought the computer?

[SXYSOL]

nah no computer yet...lookin at a microtech...what do you guys run??

[WPN.22R]

microtech LT8 great and easy to tune. does the job well.

[SXYSOL]

yeah mate said the exact same thing...

[BLKCRX]

440cc injectors with a good ecu will be more than enough.

I used to run 550cc on 7psi on my b16 crx delsol, and they sit around 40% on max rpm / 7psi they max out at aorund 18psi on 9000rpm.
Now im running 1000cc with Hondata as the ECU and there more than enough for anything so far.

Regards James

[z3lda]

1000cc, how much petrol do u use up on a trip to the local milkbar?

[BLKCRX]

I get 400km out of 35L of fuel which is better than most factory stock Honda’s this every day driving boosting a little now and then, injector size has nothing to do with fuel economy if your ecu can control the injectors 100%

When on long freeway drives i get a good 450 - 500km out of 35L of fuel. Its all to do with how well your car is tuned.


Regards James

[INASNT]

1000cc, how much petrol do u use up on a trip to the local milkbar?

yep with a good computer you can make a car with 1000cc injectors idle like a stocker. They only start flowing more once you tell to to through the comp

[TODA AU]

Rotary injectors are no good...
Wrong spray pattern...

[WPN.22R]

like i said!! rotary injectors no good for this typ of set up!!! :o

[pornstar]

they lost 5 kws between identical setups at 9 psi... stupid rotary useless mf injectors

[TODA AU]

like i said!! rotary injectors no good for this typ of set up!!! :o

So you did... :lol:
Well, you said you'd been advised...
Having been there & done that I can say so with absolute certainty... :P

[pornstar]

i can say with almost 90% accuracy that Adrian from toda cannot hold his beer :P well thats what razztech ppl say ;)

[SXYSOL]

what would be the best injector to run?? havent had a real lot to do with injectors so not real sure but it as simple as swapping between diffirent models of cars...would type R integra injectors be any good??

[BLKCRX]

Type R injectors are the same size as your current injectors ;)
how much boost will you want to run ? how much power do you want to make.. these are the kinda questions you need to answer so you can choose a injector.. but in short get 720'cc unless you go to a hipo engine 720's will be more than enough.. just get a [acronym:73257695d0="Engine Control Unit"]ECU[/acronym:73257695d0] that can control them correctly... so you keeep driveability. As for brand just get RC or semens, or delfi or delco.


Regards James

[SXYSOL]

thanks for that info...i'm only planning on running about 5-8psi so i would've said 720 are huge...man wish i wasnt in tassie and could just go in and see someone and get all the info i need....

[tinkerbell]

try this technical worksheet: http://www.rceng.com/technical.htm#WORKSHEET

[SXYSOL]

thanks man

[BRU51N]

if you wanted the injectors to spray like jets you could just cut off the heads on the standard injectors and the spray pattern would be all ugly but would feed heaps through..
cheaper option and backyard style to high flowing them in other words.

i wouldnt do it thought..

[Civic Type R]

what would i need for a fully worked JDM ITR motor ?
atm i have a stubburn Mugen ECU - which is proving to be a REAL hassle and i am running a stock Civic VTir fuel rail and pump.

.... help ..

[fueltank]

what would i need for a fully worked JDM ITR motor ?
atm i have a stubburn Mugen ECU - which is proving to be a REAL hassle and i am running a stock Civic VTir fuel rail and pump.

.... help ..

Unless the mugen ECU can be re-tuned your options are next to none.
Bigger injectors without a re-tune and it won't even idle right, if at all.

Try bumping up the fuel pressure if you are running lean or get a new ECU + injectors.

[DynoDave]

thanks for that info...i'm only planning on running about 5-8psi so i would've said 720 are huge...man wish i wasnt in tassie and could just go in and see someone and get all the info i need....
I have a few Tassie customers and they just put there cars on the new ferry to Sydney I tune there cars and they go home again and I think it costs them $395 for the trip on the boat.That might be your answer and I get down there 4 times a year racing so I can always help you out when I come down if that helps.
Regards Dyno Dave

[SXYSOL]

yeah sweet thanks for that...

if i was gunna go to sydney i'd just go to melbourne and drive up...much cheaper option... the boat to sydney is a bit of a rip off...

when are you planning on coming down next???

[shmivic]

rotary injecs are a different impedance to honda no go hunt down a set of prelude h22a injectors as they ar direct fit and same impedance also 440cc

[shecomb]

Standard H22 injectors are not that high. There more like 330cc

[ProECU]

If you're going to use RC eng injectors, I would recommend using 440's over 550's if they were the choices you have.

The 550 RC spray pattern is not ideal

[Weq]

pelude injectors are 280cc

[shecomb]

If you're going to use RC eng injectors, I would recommend using 440's over 550's if they were the choices you have.

The 550 RC spray pattern is not ideal

How about the 750cc's?? Do they have a wide angle? Like 35 degrees?

[BLKCRX]

Use 550 Low impedenace injectors and the spray is perfect ;)

550 are fine for a b18c7 up to around 14psi

[ProECU]

I wouldnt use low impedence injectors as you increase the cc of the injectors.
The Resistor blocks work well for small volume injectors, however has issues with larger injectors

I would try to avoid buying 550's off the bat, but if this is your only choice, they're still definately workeable.

Definately try avoid the resistor block solution at all costs with large injectors.

[BLKCRX]

lol oh no i don't agree there, iv tuned many cars from 440cc - 1200cc with resistor pack makes no difference to the output of the injector.



hmm even on my car I’m using 1200cc injectors now with a resistor pack.



Also Toyota Supra 550cc+ injectors are all low impedance injectors that use resistor packs, like wise with the 550RX7 injectors.



Regards James

[ProECU]

Thats OK James, I forgive your lack of attention to detail and electronics knowledge.

[BLKCRX]

hehehe ;)

[ProECU]

In all fairness, what James says is correct, however larger injectors take more time / current to open/close. A resistor box is not a good idea, but it is workable if you tune this out!

Ev