mike14_07

my 455 has 389385 b head on the passenger side and 409100 g head on the driver side. runs good but is this ok? i plan on getting a set of edelbrocks within a year but thats a ways away i read something about the b heads having a different rocker arm set up?

442Harv

No, rocker set up is the same.

mike14_07

would there be a problem with running these two different heads and what is the difference?

joe_padavano

Mike,

Can you give me a little more info on where you got that 455? I ask because I built a 455 from a PAW kit back in the 1980s and the kit came with two different heads - a B and a G. The motor and the car it was bolted into went away in the first divorce and I lost track of it. Thanks.

mike14_07

its a 69 supreme factory gold and 350, been swapped to a stout 455, 700r4 that couldnt handle it. 12 bolt posi with 4.10s. been repainted once or twice, brown interior, minimal rust factory column shift now has a rachet shifter. bout all i no i got from ok.

72 cutlass455

As long as the valves size openings are the same should run fine if it was mismatched you would know.

mike14_07

what would it i would imagine would flood one side or run lean on the other or wouldnt really run on the other

72 cutlass455

All would fire but in a mismatch one head would be doing more work. If this is Joe's old engine hehe probly has the large valve openings. Oldsmobile changed the casting letter on the bb almost every year with very little change. Would think you would get a vibration if mismatched as four cylinders were pushing the crank a bit harder than than the other four.

joe_padavano

The engine I built was in a 1971 Cutlass with a 'glass tilt front end. It was featured in the Oct 1985 issue of Car Craft. As I said, the car went away in the first divorce in 1993.