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GJF GJF is offline
Slantnose from HELL
 
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Join Date: Dec 2004
Posts: 809
Efficiency as far as what??? You can have your car idle perfectly with 72lbs injectors and have exact fuel control throughout the entire range. By adding an extra injector especially a small primary and a large secondary. You will end up having a drastic cut in your fuel map when you bring the second injector in. It actually adds more tuning into the equation with the same results as single. Back when ECU's couldn't control large injectors we had to run stagged injectors.

For example I am now running 96lbs injectors on my setup. I have a smooth idle @ 850 RPM's but can only get the AFR's down to 13.5 at idle. But these are big injectors. I could run 83 lbs injectors and gain more injector control below 1500 RPM. To be honest I usually keep the boost down at 1-1.1BAR as more than that lack of traction makes the car a handfull.

72lbs injectors would allow efficient control from idle to 650HP without worry about stagging your fuel map.

If you want to stick with stagged then go 24lbs primaries and 55lbs secondaries. With a new ECU, it won't gain you efficiency just more work.
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87 911 Carrera platform
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Old 07-20-2010, 07:23 PM
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