CFMs are one thing. Metering is another.
Changing airflow ratings without changing the air bleeds and fuel restrictions is lame. You end up with a carb that never quite works right. Like I said you need a flow bench and a dyno to properly adjust thes parameters. Experience helps too.
Again, the 390s are to lean. The airflow totals may be good, but the metering is way too lean. Take a look at your exhaust valves. They either are or will be white as a ghost.
A sleeved 950? Did you adjust anything to compensate? Did you enlarge the air bleeds, PVCR restrictions, idle restrictions, change jetting, anything? If not, I can tell you right now for sure your carb isn't metering right.
Vacuum secondaries? I know what they knew. They knew if people had a carb that was too big, it would be a lot more forgiving with a vac. secondary. You get better customer response, and can sell a lot more carbs that way. I'm not saying they don't have their place. I have one on my SBC 400 right now.
A 1 barrel carb might "work" for your engine, but would it work best? A tunnel ram and two fours might work for your engine. Show or go that is the question.
Oh yeah, and was my 5.0 fast?
The front wheels came off the ground.
It beat my friends GTO by a few car lengths. The next day his car ran low 12s all day long.
Last edited by lluciano77; 07-10-2004 at 07:56 PM.