m455sx

I was wondering if the engine could be damaged if i block the heat cross overs in my cast iron intake? My engine looks great except for the burned off paint on the intake.

Destructor

It will run lousy if you drive during cool weather and takes a while for the carburetor to warm up. I put my crossover back in service a few years ago while fixing an intake leak, much better now when driving on a cool fall or spring morning.

m455sx

I was thinking of that..... I wish they had a ceramic type paint that didn't burn off.

Lady72nRob71

I had the new POR15 paint burn off of mine, too, as well as by the exh ports.
What paint did you use?
If you block off the crossover ports, buy an electric choke conversion kit for better cold weather starts.

Destructor

I have an Eddlebrock with electric choke, the problem is the choke will open but the carburetor and manifold is still cold. I would usually drive just over a mile stop for breakfast then start the car and drive off. During that half hour or more the heat from the engine would soak into the manifold and carb by the time I finished breakfast but if I didn’t stop and just continued driving the engine would bog if I wasn’t very gentle on the gas, on side roads where I kept my speed below 35 it wasn’t so bad but if I wanted to go faster or climb a hill the engine would bog down until the carb finally warmed up. I can’t say how it will perform with a stock carburetor but that was my experience with the AFB. It would be worse if I drove in December when the temps could be around 30 in the morning, of course once the snow flies I don’t drive again until spring.

bigD

you can buy cast iron plugs from edelbrock that require a little side dressing then go in the crossover passage on the head... i'm going to try a pair of these, i got mine from summit for 9.99 and it looks to me that with a bit of shaping on the belt sander these will do a real good job. i have thought about drilling a 1/4" hole in one of them(or maybe both) to allow some heat to get to the plenum... dunno yet but i do know that i like this option to pouring the head with a zinc alloy.

bigD

you've brought up some good points destructor, in my case my main reason for running the plugs is the horsepower gains that are available with blocking the crossover... better exhaust flow. that is why i will probably drill at least one of the plugs to allow some heat to get to the manifold. i like to run a phenolic spacer under the carb as i see no reason for the carb to run much over 100 F... the majority of the atomization happens in the intake plenum anyway...

DeltaPace77

Couple things you can do. Try some high heat paint, or ship the manifold out to places like Jet-Hot coatings. My car has an aluminum Edelbrock on it that came with stainless riser block off plates. I split the differnce, and drilled some 1/4" holes in them. I painted the manifold with clear engine paint, and still looks good after several years.