cONFUSED ABOUT INJECTOR OFFSET
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Confused about injector offset 
I have been reading and reading and still can't seem to determine the correct offset for the 43# injectors that come with the new Radix kits for the 5.3. Magnusun claims that they should be set at 5.25 gms/sec but the math just doesn't support that. Even if I do a simple conversion I come up with 5.42 gms/sec and the conversion charts (injectorscale.xls or johnsinjectorcalc.xls) both show ranges from 6.3 to 6.93 gms/sec. My ltft's are slightly neg to 0 at wot so I think I am ok there. But it still feels a little lean, although I have no hard data to back that up. If I increase the rating in the offset table, am I acually allowing more fuel in, or rather, allowing less fuel as the computer will compensate for the larger pulse width by shortening the acutal pulses or increasing the time between them. I am sorry if I have really missed the boat here as far as understanding this goes, but if someone would be kind enough to show me the light I would be much obliged!!!!
Last edited by kodiakz; Feb 28, 2004 at 04:57 PM.
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Originally Posted by kodiakz
I have been reading and reading and still can't seem to determine the correct offset for the 43# injectors that come with the new Radix kits for the 5.3. Magnusun claims that they should be set at 5.25 gms/sec but the math just doesn't support that. Even if I do a simple conversion I come up with 5.42 gms/sec and the conversion charts (injectorscale.xls or johnsinjectorcalc.xls) both show ranges from 6.3 to 6.93 gms/sec. My ltft's are slightly neg to 0 at wot so I think I am ok there. But it still feels a little lean, although I have no hard data to back that up. If I increase the rating in the offset table, am I acually allowing more fuel in, or rather, allowing less fuel as the computer will compensate for the larger pulse width by shortening the acutal pulses or increasing the time between them. I am sorry if I have really missed the boat here as far as understanding this goes, but if someone would be kind enough to show me the light I would be much obliged!!!!
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Joined: Nov 2001
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From: Las Cruces, NM
Originally Posted by kodiakz
I meant injector flow rate instead of offset. Sorry, still much to learn here!!!
The number you stick in ls1-edit will be lower than calculated for the most part. To make the car run richer you put in a smaler value, larger values lean out the car.
Gary
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Thanks for the reply. It is an '03 blown avalanche. Fuel pressure is 60psi. So you are saying that pluggging in 5.0 gms/sec as apposed to the current 5.25 would actually serve to richen it up? HOw much of a difference do small changes in flow rate actually make?
