largest injectors
#1
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i read yesterday about the 305cc or 330cc injectors on the standard 1.6 ecu(1991 model) will run.
do you have to do any mods......
if so is idle ok and will you see any power gains.
i have the 1.8 injector at present in my 1.6 greddy turbo,intercooled bipes fmu walbro 255 forge boost controller forge wastegate and bov.
186 bhp flywheel @5,500 rpm.
do you have to do any mods......
if so is idle ok and will you see any power gains.
i have the 1.8 injector at present in my 1.6 greddy turbo,intercooled bipes fmu walbro 255 forge boost controller forge wastegate and bov.
186 bhp flywheel @5,500 rpm.
#4
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if you have the factory AFM it just takes a drill and a screw driver to idle them. the AFM has a screw to change the idle mixture, just as the TB has a screw to change the idle speed. Tighten the screw and you'll have a richer idle mixture, adversely loosen the screw and see a leaner mixture. When idling my 305cc injectors it took one complete turn looser to have a perfect 14.7 AFR idle. Your really must tune with a wideband or on a dyno.
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Is 14.7 the "correct" factory afr? Curious because since the begi fmu mine idled at 15.7 with the original blue tops and the same with the current tan tops. When I adjusted the clockspring tension and idle mix at the dyno and got no change in my wot afr, I adjusted it back to where it was before I touched it. 15.7:1
#9
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if you have the factory AFM it just takes a drill and a screw driver to idle them. the AFM has a screw to change the idle mixture, just as the TB has a screw to change the idle speed. Tighten the screw and you'll have a richer idle mixture, adversely loosen the screw and see a leaner mixture. When idling my 305cc injectors it took one complete turn looser to have a perfect 14.7 AFR idle. Your really must tune with a wideband or on a dyno.
#10
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Is 14.7 the "correct" factory afr? Curious because since the begi fmu mine idled at 15.7 with the original blue tops and the same with the current tan tops. When I adjusted the clockspring tension and idle mix at the dyno and got no change in my wot afr, I adjusted it back to where it was before I touched it. 15.7:1
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Yeah, it seems ok to me. It's only ~15.7 at ~850 rpm idle. Add the smallest possible amount of throttle (~1000 rpm) possible and it richens to 14.7.
I was curious because I'm working up the energy to bolt on the rx7 afm, and I need a target idle afr.
I was curious because I'm working up the energy to bolt on the rx7 afm, and I need a target idle afr.
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which year? yes, replacing the factory fpr could work. although depending on your year bumping up from 265cc to 300cc might be ok for the ecu to handle without adjustments, only a 10%-or-so increase.