I have a 413 -3 head that I want to do cut aways on the ports to find the thin spots and where the water is. Would a 14" chop saw with a metal cutting saw blade work, or would I need to take it somewhere that has an industrial sized band saw?

Not at all interested in hearing how bad the heads are as they will be used in an RV application and are perfect for that purpose.

a band saw would have a thinner cut, would not need to be that big of a saw just go slow

Been there and done that. Was a total waste of time and money. Unless you're hogging these out for a prostock application there is sufficient material in all the right places for a mild porting job. If you plan to port to the max, cutting one head to see thin spots doesn't mean the head you port will be better or worse. You'd be far further ahead to buy a set of the Direct Connection porting templates and use those. Those pretty much guaranty you won't grind into a water jacket and the end results actually provide a performance gain.

Thanks for the input. These are a different casting altogether than a regular big block. Completely different. I guess I might be better off grinding on a spare head to see. Particularly concened about hitting water as these have water all over the place even cooling the spark plug.

If they're being used in an RV, just what are you hoping to gain by hogging them out? I think you're flogging a dead horse.

Isn't the 413-3 that goofy big truck engine with the oddball heads, water pump, intake, exhausts, and a bunch of other differences compared to a typical RB?

Yes it is.

yes a 14 in chop saw will do it.

Yes, that is why I was considering cutting one open to see what is what. Next to no info out there about anyone playing with them. Among the goofy differences are a large closed chamber and a spark plug in the center like a small block head.

I use an ultrasonic tester when porting it reveals everything. They are a little pricey, I bought a new GE for about $1500 20 years ago, maybe find a used one for sale.

A big bandsaw works the best but you can try the chop saw. Wear some ear plugs and eye goggles, it will be noisy and you'll have chips and sparks flying around.

One of our members posted some very nice pictures of a 906 head cut up on Facebook. I should have probably saved those pictures but I stick to porting aluminum only now.