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RarlyL8 RarlyL8 is offline
Crotchety Old Bastard
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,521
I agree with everything you said Randy, the trouble is that I have yet to run across anyone who has optimized thier CIS and then, with no engine changes, swiched to EFI. There is no exact comparative data.

Unfortunately sequentially fired fuel injection is too expensive for most hobbyists. Optimizing the CIS they already have is the best choice for the situation.

Fuel mileage can be greatly enhance in a CIS engine by straightening out the A/F ratio throughout the RPM range, from idle to redline. I don't have any data on track use but I know of a few modded 930s that get 21-24mpg on the highway. That is very acceptable for a hobbie car.
RarlyL8 Motorsports / M&K Exhaust - 911/930 Exhaust Systems, Turbos, TiAL, CIS Mods/Rebuilds
'78 911SC Widebody, 930 engine, 915 Tranny, K27, SC Cams, RL8 Headers & GT3 Muffler. 350whp @ 0.75bar
Brian B. (256)536-9977 Service@MKExhaust Brian@RarlyL8
Old 02-28-2007, 06:28 PM
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