Fuel system upgrades for dummies.

[Gold Digger]

Hey crew, got some questions.

Does anyone have pics of 440cc MK III supra 7M injectors wired into the RB20's? i.e. the resistors wired in.

Also, if I want to use a BOV that does not recirc, what do I need to do this. And if your engine didn't come stock with a recirc type BOV, will venting to the atmosphere cause any problems.

Also, can someone point me in the right direction for learning about A/F ratio's when upping the boost of the engine.

I guess what I am asking, is can someone explain in layman's terms what I need to do to upgrade to 440cc injectors, how to vent to atmostphere, and fuel control and other ECU upgrades?

Thanks.

I have tried searching, but we all know that search engine doesn't really return the results we are looking for, and you have to use the correct wording.

[SeVa-S13]

I'm at work so I can't type up a novel but;I haven't used 7MGTE injectors, so I can't say for sure there, and hearsay doesn't help. =\To run the injectors properly however, you'll need engine management of some sort to scale back the injector pulse width. (what determines how long the injector fires, controlling the amount of fuel)SAFC's, Emanage's, and chipped/hacked ECU's can all handle that, aswell as Standalones of course.

Venting your BOV will cause problems more than likely. Some piggybacks have an feature that's supposed to help keep the engine from going pig rich when venting (SAFCII's DecAir setting), but some people still have problems.I personally just run blowthrough MAFS setups if I'm venting my BOV; it eliminates that problem, aswell as any boost leaks that are before it.

For AFR's, you'll need a wideband of course, as an AFR gauge hooked up to a stock O2 sensor is just a worthless light show. People will argue over what your AFR's should be on and off boost; I try to be around 13-13.5:1 off boost, and around 12:1 on. A working knock sensor and a sharp ear are also useful tools here.

[Gold Digger]

Thanks SeVa.

One question. What is the advantage of having a blow-through style MAFS. I saw the pic of the one on the Datsun. Would the advantage being that it's monitoring air after the turbo?

[SeVa-S13]

The main advantage as far as I'm concerned is what we covered here: vented BOV and any minor boost leaks (there is always minor leakage) before the MAFS are relatively inconsequential.Plus, running an open turbo, or even a velocity stack on the compressor inlet is bad ***. (although pretty dumb if you want the snail to last, ha)

[Carl H]

its not hard to wire in the resistors for the injectors, roy on skylines australia did a writeup which is currently in the faq section of the site on SAU on how to do it properly.as for tuning, you will need a wideband o2 sensor, greddy makes a gauge style but there are TONS of them out there, just look and you will see.as far as blowthru maf only good for large cams/turbo and if you are having reversion problems otherwise drawthru works fine, besides bovs are for ricers.