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Randy Blaylock Randy Blaylock is offline
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Join Date: Nov 2004
Location: Pacific Northwest
Posts: 342
The benefit of EFI coversions, particularly in the context of CIS, is the elimination of the significant airflow restriction created principally by the CIS plate and housing, and the convoluted pathway that the intake air must take getting to the compressor inlet.

It's easy to quantify. Just jump the relay receptacles to turn on the fuel pumps, pull off whatever housing you have covering the flapper, and try pushing down on the plate. You will be astonished at the force it takes to move the plate, the same movement that has to occur for air to move past the plate in vacuum. Eliminating the CIS fuel metering hardware, and switching to electronic fuel control has been proven to regularly net 75 hp, with no other hardware changes.

Secondarily, and not insignificantly, the superior fueling control or resolution of EFI systems, particularly when using sequentially fired injectors vs. batch fired, nets a dramatic decrease in fuel consumption.

Interestingly, if a person tracks his car enough, using race fuel, over a given interval the differential in fuel consumption between CIS and EFI is great enough in cost recovery to actually pay for the EFI conversion itself. Not to mention the extra 75 hp minimum that comes along with it...
Bullet Racing #22 GT3 Cup

Last edited by Randy Blaylock; 02-28-2007 at 03:49 PM..
Old 02-28-2007, 03:46 PM
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