Additional Coolant Routing

[68Formula]

On the Pontiac V8, behind the middle two exhaust valves on each bank there is an ajoining exhaust passage that leads up the the intake manifold. The idea is when the either of the two valves open it sends hot exhaust up to the manifold for faster warmup and driving in cold climates. Most people simply fill this with aluminum.

I want to keep detonation at bay using pump gas (as low an octane as I can get away with). So, since I am still using the heatercore my plan was to tap the rear of the heads using -6AN fittings, and the tee them into the heater core. This would better balance the heads at the two rear cylinder banks.

Now the heads I bought already have had the center exhaust ports welded shut at the valves. So unlike filling with aluminum, it's an empty cavity. I thought maybe I could take this to my advantage.

Here is my idea. Cut the heat crossover of the intake from the plenum flush to the intake flange. Bore out the exhaust hole in the flange so it's round, and then tap a pipe thread in it. (This could also be done by tapping into the head and just cutting off the flange completely, but since I'm cutting so much of the manifold I'd rather do that). Now run coolant lines from this (each side) to the front water crossover. Then drill from the water jackets in the head to the exhaust crossover, thus making it part of the wet cooilng system. My theory, this would keep the center two cylinder ports (which seems would normally be the hottest) more even with the outter two cylinders.



This would be quite a bit of work I know, but the cost is relatively small so I find the idea very interesting.

1. First question (since I don't have a head available to look at), is there even a jacket close enough to drill in a connection?
2. Will this work as I think it will?
3. Is there a way to do it better?