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Old 03-08-2009, 10:14 PM   #1
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Default Injector question

Searched some but didn't find what i was looking for. In a different situation from the other threads i saw.


I can get some purple top rx7 injectors that were recent cleaned and 2 flowed at 548cc and 2 flowed at 588cc, that lead the owner to think their not purple top lol.

I was just looking for 550cc injectors but can a 550cc purple top flow 588? I figure having more can never hurt, but just wonder if I'll run into a connection issue if they're different.

Any thoughts?
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Old 03-08-2009, 10:22 PM   #2
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Im pretty sure it can flow a bit more. just my .02
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Old 03-09-2009, 12:07 AM   #3
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my 550's did 552 and 566 according to injector rehab.
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Old 03-09-2009, 12:13 AM   #4
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Yeah, even matched at 2%, your still looking at what, 10cc's +/- at best, so I wouldnt think 20-30psi is a big deal. Im sure they are all the same injectores. As long as they are all purple and all have matching plugs, it should be good to go.
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Old 03-09-2009, 12:49 AM   #5
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If they were all flowing 588 or something like that I wouldn't be worried about it, but as is two of those injectors are flowing about 7% more. I would be worried about the cylinders that are running 7% leaner than the other two. If you keep your tune relatively rich and don't have to pass any emissions tests it would probably be OK, but why not just try and get 4 matched injectors and not have to worry about it.
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Old 03-09-2009, 12:54 AM   #6
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yeah that's a terrible match. my purple tops tested out to like 1.1% variance. you cant tune each cylinder individually and your wideband only gives you the average AFR.... so having those poorly matched injectors is like a death wish for 2 of your pistons.
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Old 03-09-2009, 10:23 AM   #7
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Quote:
Originally Posted by therieldeal View Post
yeah that's a terrible match. my purple tops tested out to like 1.1% variance. you cant tune each cylinder individually and your wideband only gives you the average AFR.... so having those poorly matched injectors is like a death wish for 2 of your pistons.
Only if you're a fucktard assflute and tune to some stupid AFR that's not 11.5:1.

I just pull the plugs and look for lean-ness after a dirty 4th gear pull where I turn the car off and coast down to a stop. Then pull the plugs and see if you have a lean burn in any cylinders. If like this, then you're ******* up, par for the course with your pathetic virgin existence. lol You can easily tell if you need more fuel or not.

Everyone can keep talking **** about my "super fat AFR" and act like a ------. I don't care, my motor is still raping and spitting.
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Old 03-09-2009, 02:11 PM   #8
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I figured if all the injectors could flow the needed amount that it wouldn't matter that two of them are flowing higher. Or is it percentage based?

Could I just have these injectors recalibrated to '550cc' ? I do realize its more efficient if you have a set of matching injectors, but if I can grab these, having them recalibrated for $20 a injector I'd still come out ahead vs some RC injectors.
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Old 03-09-2009, 02:28 PM   #9
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I would just put the two higher flowing injectors on cylinders 3 & 4 to compensate for poor coolant flow.
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Old 03-09-2009, 03:54 PM   #10
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I wouldnt run a set of injectors with that much varience. Ive seen that style of injector flow anywhere from 550 to 600. You ideally want to be within 2%, 3 is doable, but anything over that i would not recomend on a Turbo Setup.
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Old 03-09-2009, 09:46 PM   #11
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different injector flow = different AFR in each cylinder = different amount of power coming from each cylinder. meaning its not going to run very smoothly either.

7% variance on 11.5:1 afr = 12.3:1
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