TheBigBlueBoat

I've got a 1970 350 2bbl in my 70 S. It's got an unknown but fairly lumpy cam, loose converter, and 3.73:s from the previous owner that all seem to work pretty well. But I can't help to think I'm leaving a lot on the table with the stock 2bbl carb and intake. (though that deceptive top end did make it quite the sleeper back in the day.) I'm thinking an Edelbrock Performer RPM topped with a Qjet ought to be a good match for this combination as it seldom spends any time below 1500 RPM anyway, and it will be all the better when it gets upgraded in the future.

Any thoughts on this combination? And if it will work, can I expect any significant gain? I've got to think the current top end has got to be holding it back some.

cutlassefi

You’re half way right, RPM Intake is a good choice.
But Qjet isn’t in my opinion. I’d do a QF or Brawler 750 that has changeable air bleeds and power valve circuits and more. That would be the best bang for your buck.

olds 307 and 403

I usually endorse the Qjet due to the spreadbore and triple stack boosters. But with 3.73 gears and a 3 spd, mileage will not be good, no matter what carb is on it, so Mark's recommendation is spot on. Yes, you are leaving power on the table with a 9 to 1 350 with a hotter cam. Headers and dual exhaust are also a good idea.