Had to stop restoring my 58 as my wife's 69 Skylark developed a fatal failure. I'm nearly done rebuilding the 350 and did some warm over old school hp tricks (like removing front to rear barrel divider untouched left to right, port match heads, intake, exhaust, open up exhaust manifolds, etc). I don't want the qjet to get hot and boil out gas again. It's also a hp trick on nailheads so I wonder if there's any gain from blocking exhaust heat to the intake? I've heard many ways of doing this but before I decide to I need to know if there's a gain from doing so. It has hyper pistons, rv cam, and focusing on low end street torque BTW. Thanks guys
I did it to my 350 I recently rebuilt. It will affect your choke operation if you are using it. I converted to electric choke. To block it, I used freeze plugs in the heads. Mine were 3/4" and I bought them from Summit Racing, part number MEL-MPC-38B
Freeze plugs or threaded pipe plugs. Unless you drive it in the winter having no choke isn’t a big deal ( to me anyway)
Thank you guys for your insight. Ille plug the ports before bolting the heads back on. Is there anything we can do about coolant in the intake? Nailhead intakes are dry, but small and big block are built with coolant runners (wet intake). Does the coolant flow run back to front or left to right to complete the coolant circuit?
As far as I know it runs into the block with the water pump, gets pushed to the back and then comes forward in the heads and out the thermostat housing.
Sounds like the ports can be blocked at the intake to keep it even cooler. Has anyone done this on a wet intake?
When I had my heads ported, I had my guy block the heat ports. It takes noticeably longer to heat up even after it only sits for a few hours, but that's no big deal to me. As far as a performance increase I couldn't say. It went from a old mild rebuild (done by previous owner) to my build with bigger roller cam, roller rockers, h-beam rods etc....
Are you going to run the SP3? I never realized it till awhile ago, the SP3 has no provisions for intake heat (crossover) so plugging the ports in the head is moot.
Good point! I didn't order it until after the heat passages were already blocked. Oh well live and learn!
Don’t feel bad, I went thru the hassle of blocking mine on my new irons I ported, didn’t even think or realize there’s no provisions for crossover on the SP3, and I’ve had the SP3 on and of multiple times, I feel stupid
My SP3 doesn't even have them. But then again I am running the Sniper system. Cold starts shouldn't be a problem. either way, she doesn't see much cold weather driving. Tim
