4 larger injectors vs. Additional Injector Controller?

[rustrocket]

For my turbo ka build, i'm pondering if i should upgrade to larger injectors (680cc?) or add another injector and use an AIC? What are your thoughts on this?

Thanks

[SR240Z]

wouldnt it be easier to just run the larger injectors, since you are going to be running a standalone of some sort im assuming

[thehelix112]

If you install and control and additional injector you are relying on the manifolding for correct fuel distribution and to no puddle the fuel. Upgraded injectors is the proper way to do it.

 

Dave

[ProjectSR20]

I agree with helix. You would have to make sure that your fuel is atomizing correctly, otherwise it will form into droplets that are larger than ideal, thus hurting you power output and possibly causing a lean condition. This is along the same lines of why I decided not to do a 4 barrel swap on my L24.

[Clifton]

You won't have any more of a problem with fuel with an AIC set up as carbed guys have. Injectors spray pretty fine and the air is moving pretty fast on boost. My power was pretrty good with it:smile:. I've run an AIC on 2 cars and a truck. I just took an HKS AIC on off my 73' Z. I could never get it lean enough up top without being too rich on the bottom, or vice versa, PITA compared to the safr I have now. I would go with larger injectors and an safc or safr. You can pic up those piggy backs used pretty cheap too.

[rustrocket]

Thanks for the advice. Upon researching the safr and safc, i found the MAP ECU. Have any of you guys used this? check it out : http://www.performancemotorresearch.co.nz/

[cheftrd]

The problem of the AIC is not one of atomization, but one of distribution. Dry-flow manifolds (most EFI) do not distribute fuel evenly among the four cylinders. A good AFR can show in the down pipe if one cylinder is rich and one is lean. Proper AIC operation needs one additional injector in each runner. If you're worried about idle quality with big injectors, buy engine management that has staged injector capability.

[ProjectSR20]

The problem of the AIC is not one of atomization, but one of distribution. Dry-flow manifolds (most EFI) do not distribute fuel evenly among the four cylinders. A good AFR can show in the down pipe if one cylinder is rich and one is lean. Proper AIC operation needs one additional injector in each runner. If you're worried about idle quality with big injectors, buy engine management that has staged injector capability.

 

What would some of the ones on the list with staged injector capability?

[cheftrd]

What would some of the ones on the list with staged injector capability?

 

SDS

Haltec

Motec

DFI

TEC3

and lots of others.

 

Two injectors per port. Idle on 440's but have 880cc worth of injector per port. Four injectors run up to about 30-40% duty, then the other injectors come on line.

[mobythevan]

I just installed 850cc injectors on my Talon 4G63 engine. I believe MSnS also supports dual staged injectors. I am not going that route because I talked to someone tuning 2 liter four cylinder engines with 800-900cc injectors and got some tips on smooting the VE table at idle and lowering fuel pressure a pound or two for fine tuning idle. So I am going to try that and see how it does.

[Hugh]

Unless you're going to make a crapload of power, reasonably big main injectors will cover everything.

 

Staged would be cool if you need 1000cc's or more per cylinder, but chances are you won't make that kind of power. (unless you're planning for 600+ or something)

 

Running an AIC (like a Rebic for example) is an outdated tuning style. It works ok, but not so great. It's too touchy and volatile.

 

I would keep it simple and get large main injectors.