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kellcats521 kellcats521 is offline
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Join Date: Feb 2005
Location: Atlanta Metro
Posts: 219
Originally posted by DonE
I use 60lb Siemens and at WOT (520rwhp), they are around 72% duty cycle - the larger inj were around 65% duty cycle at WOT. The 60lb inj provide much better low end throttle response and idle than the 72lb Siemens used earlier. I just could not get the big injectors to provide a good spray pattern at 1.5ms (idle) like the 60lb inj can - I think they dripped rather than sprayed. I think your inj size will also be dictated on the ECU you use as well.
This is VERY important - too large an injector will manifest itself with poor idle/off idle performance, especially if you use the Bosch pintle-style injectors. I think Siemens are disc style, which seem to work better at very short PWs, but in any case you need to balance this out if you're planning on street duty with your car.....
Old 06-14-2007, 07:07 PM
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