Inliners International Forums General Discussion Engines 1 bbl Holley Pro-jection

While searching around on the net I found some info on a Holley 1 bbl throttle body kit that doesn't appear to be in production any longer. Does anyone have any experience with it replacing a 1 bbl Rochester?

I ran one of these 1bbl ProJection kits several years ago on a 292 in my Nova. Driveability and cold starts great, high RPM power nothing special. Not sure if that was a limitation of the EFI system or the mild cam I was running. I did have an O2 sensor readout only, not feedback, so I think the tuning was pretty close. Bottom line in my opinion is if you want a simple EFI system that runs decent go for it. If you want to go fast you need something different.

I also have run the old analog ProJection 2bbl system on several small blocks with similar results. Starts easily and drives fine but carburetor beats ProJection for both fuel economy and power.

Stroker6, was the 2bbl projection you were running pre feedback (no 02 feedback to the computer) as well?

I can see the Carb beating it on power (as IIRC they aren't particularly large in the airflow department) but the fuel economy statement is somewhat of a surprise.

For street use, fuel injection without closed-loop operation will be inferior to a carburetor most of the time. The whole point of FI is to get the control that comes with closed-loop, that a carb can't do.

I did a lot of reading about ProJection, and most people who hated it or had problems did not run closed-loop, those that liked it ran closed-loop. I think it was a mistake for Holley to offer it as an open-loop option for the street.

Both systems I ran were the old analog open loop type.