injectors/afc question.

[turboweege]

can an old style afc (-30% to 30%) turn down dsm 450cc injectors low enough for a turbo setup on my 90? or should i buy some smaller ones or jdm?

[encasemyheart]

270cc injectors come stock, you would be able to control +- 30% on the 450cc injectors, that means the lowest they could go with the old style AFC would be 315cc, so no.

The newer one at +-50% would be fine, you could control the injectors to 225cc.

[turboweege]

well what about after adding things like headers, exhaust and intake, would that warrant the extra cc's? and also would they work for when i go ka24et???

[oi138]

No you have enough fuel w/ stock injectors to warrent roughly 200 rwhp.

[huguetpj]

No you have enough fuel w/ stock injectors to warrent roughly 200 rwhp.

As long as he is using a RFPR. Stock injectors with stock fuel press won't cut 200rwhp.

Now if your going with bigger injectors I wouldn't recommend using a RFPR. If you can tune it down to 315cc it might work. I beleive Adam was runnning 310s in his KA24ET without any fuel management. It was rich at idle but he says it worked.

You can always try it out and if it doesn't work change AFCs.

Intake makes no real difference in a turbo setup (except for making the compressor's work easier), and headers are not used in a turbo setup.

[oi138]

I was just making a point to the fact that intake, header, and exhaust (i don't think he has a turbo yet) will not warrent extra fuel the stock injectors can't handle. That's why I said roughly.And the stock fpr is a rising rate.

[Matthew]

Once you go turbo, 450cc - 30% should be fine. If for some reason you can't get them to idle or you still run rich, you can also lower the fuel pressure with an adjustable regulator.=Obviously, you have no businnes running 450cc injectors (even at -30%) on a non-turbo car. Even with bolt ons, you shouldnt be maxing out stock injectors, It's once you start running a higher compression ratio that you'll need the extra fuel.My concern is, arent DSM injectors low impedence, while 240sx injectors are high?

[huguetpj]

Quote »I was just making a point to the fact that intake, header, and exhaust (i don't think he has a turbo yet) will not warrent extra fuel the stock injectors can't handle.[/quote]

You're right, but he did say "turbo setup" and I didn't read the only I/H/E part jeje :pface But for only I/H/E changing injectors it really not worth it.

Quote »And the stock fpr is a rising rate.[/quote]

Yep 1:1, I meant 7:1 or higher, sorry for the confusion

[sil80drifter]

Can impedance be changed with resistors added onto the injector wires? I am planning on getting 460ccs from a 2nd gen RX-7, and I won't be runnig beyond 10psi on a t04 (most likely t3)., so the HP numbers should match their capability well. Btw, if anyone can get ahold of an 87.5 (mid year model) 1st gen RX-7 GLE-SE, they have 2 760cc injectors (only two because they are so big)... so u need two 1st gens to get 4 injectors. Don't bother with the non GLE-SE models, they are all carbureted (no injectors). But it'd be worth it...760cc!! whee.

KA-ETs rule!

I'm makin one this summer too.

sil80

[oi138]

You're right, but he did say "turbo setup" and I didn't read the only I/H/E part jeje :pface But for only I/H/E changing injectors it really not worth it.



Yep 1:1, I meant 7:1 or higher, sorry for the confusion

Yeah i know what ya meant i just come off as an *** sometimes. lol

[huguetpj]