I agree with Dave and Joe about using exhaust heat.
I do not see why water is better either, exhaust is quicker to get heat to intake.
Also, less tubing or long water hose.
I have used exhaust heat on my 235's with Fentons and tube headers with no problems. The factory uses exhaust instead of water.
The exhaust heat is routed per tubes from the manifold to a plate on bottom of intake and not open air from header heat.
Or, the tubes can be routed from bungs welded at top of exhaust pipe(s), if do not want to route from exhaust manifold. The tubes can be hidden better from the pipes too.
I will be doing the same on the 250 I am working on now.
As Joe said, if a leak, you will only have exhaust noise but not a overheated engine from loosing water.
