Bob,Bob Hollinshead wrote: ↑Fri Aug 05, 2022 12:29 amSteve, what minimum CSA do you calculate for 377 at 7K rpm? Are you using a version of pipemax? I have a pair of these I'll be playing with soon hopefully, the first thing I noticed when I took them out of the packaging was how tight it was at the pushrod pinch. Planning on 2.08/1.60 valve.steve cowan wrote: ↑Thu Aug 04, 2022 11:02 pmI calculated using a mach index of 690 ft/ sec for your cubes at 7000 rpm a minimum csa of 2.35in2 factors in radius,1980RS wrote: ↑Thu Aug 04, 2022 8:38 pm
I am going to use my Ported 2925 S/V on these heads since it's ported to the 1206 gaskets and the new heads are about that height in the opening. I have to tell you the pinch when I checked them against my Dart 200s were a 1/4" smaller. Anyone see a problem with that? otherwise everything is almost identical to the Dart heads.
The new aluminum heads bare came in at 20 lbs.
The cast iron Darts came in at 50 lbs.
So 60 lbs. of the front of the car and another 30 lbs. off with the new aluminum radiator deal, close to 100 lbs.
Not sure if you can get area without blowing the pinch out.
Otherwise all you can do is make it as big as possible.
Not sure what bore size you are using so here is the equation, be mindful it's a starting point and not set in stone.
Bore2 x stroke x rpm x 0.00356/ 690 = MIN CSA.
using my 383 as an example-
4.030 x 4.030 x 3.75 x 6600 x 0.00356 = 1418/690 = 2.05" min .