Thanks Joe
Looks like my springs are either shot or too short, even tho the head rebuilder indicated they were OK. I pulled a couple and measured their free height and got 2.06" on both. The exhausts have the roto caps so that settles those questions.
Research at Rock Auto has turned up a couple differing options.
The truck 235 doesn't detail roto caps and has a 2.16" and 2.156" offerings.
The Vette & Bel Air 235 does detail a spring for the roto cap. It is listed at 2.281", Another offer is listed at 2.25" but doesn't indicate if it's for a roto cap. One other is listed at 2.156 and is the same part# as the truck spring and it indicates that it is not for the roto cap.
So I'm looking at either a 2.281" or 2.25" spring set which is considerably taller than whats in the 848 head now.
The reasons for checking the head is basically due to erratic vacuum readings and a leakdown test that showed leakage in the valves. The engine is freshly rebuilt and the head has new exhaust valves and hardened seats, new intake seats, recut intake valves and new guides. Relapping has got all but #4 & 5 exhausts sealing up good. 4 & 5 exhaust will weep alittle gas after 30 secs or so when the port(s) is filled with gas.
The head rebuilder claims the valves will eventually seal with use and has rechecked the head and says it's GTG. We've both relapped them now. Before I slap it back on I'm going to replace those springs and hope he's right, just got to decide which length.
