Clamshell - to poppet or not to poppet?

[9D280]

OK, simple Q. It would appear the latter half of the Clamshell production run didn't have either a poppet valve or a thermostat.

I can see reasons for putting them back in (better temp control at idle, not chilling the block down excessively) , but I can also see why they may have been deleted (apart form the obvious cost save - my cooked pistons are a good demo).

So, Q to he usual crew. Having just found a spare exhaust cover (flange face on mine was corroded to the point of not sealing) from an '88 Mariner (i.e no 'stat or valve) and fitting it to an old 650 block (which had the poppet seat removed already), do I install or not?

Everything so far is swaying me towards not. Any thoughts out there for or against?

[davej]

I have a 60hp 1987 merc which doesn't have either the poppit or the t-stat and it works fine. Its nice and simple with one less thing to crud up and go wrong.

Davej