[601HP]

Knowing what I do now, I would purchase the Holley BJ/BK set from Carl's, or Survival Motorsports' similar set-up. Those carbs are far better matched throughout their operating range, than bolting on a pair of Holley 600's as I did years ago.

My original pair of 600's always ran too rich because of; the air bleeds (idle and high speed), transition circuit, and other tweakings needed. This wasn't a poor combination, but it could have been better. I've been told the 600 was essentially designed to be run as a single carb application, and when used in a dual configuration, fuel distribution in certain portions of the operating band result in a rich condition. I subsequently found that to be true, in my application.

Just this year a fellow Cobra owner shared a lot of carb tuning data with me that he put together through extensive wide-band tuning efforts, various sensors mounted on his engine, and documented it all via a laptop. He also spent considerable time on the internet gleaning info from other sources. I copied his efforts, and spent a lot of hours modifying, tapping, drilling, adjusting and tuning my 600's. I made some additional changes to my setup that helped further tweak my engine. The engine runs noticeably cleaner, and driveability has been enhanced especially between off-idle and 3,000 rpm.

I enjoy fiddling with things as I described above. Some folks may not want to invest the effort I did, and would rather bolt-on multiple carbs that are nearly ready to be driven. My efforts to modify the 600's would probably not be necessary if the BJ/BK's were used instead of the 600 cfm 1850's.

David