I just figured its over 25 years old and wouldn't hurt to be replaced. Thanks maybe ill just paint it or powdercoat it.

If the water passages look decent, then no biggie there. Just clean her up, paint/powderccoat and let her go. That'll save you some money for other things (a retro-fit hydraulic roller would compliment the heads nicely!).

TZ

Be sure to check the metal straight below the t-stat.on the floor of the manifold real good.

Trying to find the right head.... can anyone tell me what the chamber size in the heads is? if its open chamber or closed? and what the combustion chamber cc is? I can take it apart and put it back together but havnt a clue to any of this. Gen IV 454 mag rectangle port heads. Thanks in advance

They are 188s, open chamber, 121cc (sometimes this is may be advertised as 118cc I think, but typically cc at 121). 2.19/1.88 valves, 320-325cc intake runner port.

Edit: I agree, the stock high rise dual plane intake with the brass lined ports is a good intake.

Thanks for the help guys. Went with a pair of dart iron eagles and edelbrock air gap manifold. Will be doing a roller cam this winter.

I am running 308 eagles as well.

Did you notice any power increase with them? Or are you running a roller setup already? Also did you have to measure pushrods or did stock work?

You will need longer pushrods. Yes they make more power, much better head than the stock gm, but I have other upgrades including roller cams. I am running mid 70s with more tuning needed. Boat ran 68 with stock 420s.

Thanks for the help! Parts will be in Monday I'll let you guys know how she turns out.