Head Gasket Work...Whatelse to do

If you are thinking about a non-stock cam, don't let them shave the heads. Expect performance and/or PTV issues if you do.

The issue becomes even more problematic when a Non-PI bottom end is mated with PI heads. As this combination reduces pistion to value clearance.

A search of the forurms will pull up examples of what could happen when a mild cam is fitted on a PI swap.

If done, degreeing the cam is a must.

If you have a choice, don't shave the heads regardless of application.

The Ford MLS gasket is really good and I have used the Fel-Pros without issue.

Obviously, get some new valve seals in the head. There is probably some easy clean up in the valve bowls to help the flow out a little bit, but that's about it for easy gains.

Porting is not a problem, decking the heads is. But if porting, either have it done by someone who knows what they are doing or learn and do it yourself "slowly". Contrary to popular belief, simply maxing out the port size does not in itself mean more power. Larger ports mean lower velocity and unless the engine is cammed and built for it your performance will suffer. The trick is to smooth out the port by removing casting flash and smoothing the radius of turns. If you are not comfortable with working on your engine I would suggest letting someone else do any porting you want.
Oversize valves and a good quality multi-angle valve job are worthwhile. New valve seals are definitely a smart move as previously mentioned. Cams are the best way to change the personality of the engine but you do have to pay close attention to your piston to valve clearance. With new cams - use appropriate valve springs.
Decking the heads is a bad idea because while bumping the compression up slightly you will bring the valves closer to the pistons and with your PI swap they are already tight tolerances. If you insist on doing that, you will have to have valve reliefs cut into your pistons and for the work the gains are not worth it IMO.

97GTSTANG said:

is there much of a HP gain from a stage 2 port and polish heads to a stage 3? is it worth the extra few hundred? is it possible to have a stage3 port and polish pi heads with a stage 1 cam? will it clear the stock 97 pistons or will i have clearance issues?

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Depends on what company's heads you are looking at. Stage 2 and stage 3 are just arbitrary numbers that someone put to the heads that usually indicates a more aggressive port. Know that 'stage 3' is not always the best option- it depends on your cams, the rest of your setup, and what you plan to do. For a DD you are probably best off with a 'stage 1' or 'stage 2' port job combined with a decent 'stage 1' or 'stage 2' cam (don't just look at comp... look at MHS, hitech, etc.) Otherwise if you have aggressive heads and cams than you have no low end power, a slow build up in the mid range, and have a screaming top end.... you are pretty much going to be driving around a S2000.