Rear Crossover on intake manifold
 

Anyone ever put a rear crossover tube on the back of the intake manifold to help eliminate hot spots in the cooling system (heads) and have a more even water temp. You would run a tube from one side to the other with a T in the middle and run a small discharge hose overboard.

Mike

I ran tubes from the rear passages up to the front passages. I'd think your's would work better. Just didn't want to add any dump ports in the hull.

Can't view you pic, but I get the idea. I think running a dump would help with high water pressure also. I peg the gauge at wot.

Nice lines:D

I have run mine from the rear to the front 3/8 lines work well. Others I have known to just dump them over board. Dyno testing proved without mild and up built BBCs didnt last long without the mod.

I agree with it lowering the water pressure. I did not have a pressure problem, so it wasn't a factor on my setup. I know of 1 member who did dump the rear jackets into the exhaust tubes at the transom for a cleaner look and to control his pressure.

My current boat also pegged the WP gauge at 3500rpm. Stock 502MPI's. Easiest fix was the Merc relief valves.

OK - you guys confused me, would you do this mod to lower water pressure or reduce temperature hot spots in the heads? Uneven temps would be my concern.

Do it for both. Thats my idea anyway.

We have been doing that for years. I usually run # 8 Aeroquip hose from front to rear. As discussed earlier this mod works very well for equalizing chamber temps. It will never hurt you.:cool:

On my Scarab I ran a #12 from the rear to the front T ing into the front then going to the headers.

My Hustler Whipples came with a 1/4 line dumping overboard.

I guess its releaving steam/air pockets.

Scarab pick ya kinda can see the #12 T fitting on the front