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OK, I am currently in the process of building an engine for my car (hybrid). I have at this time a spare 2.5L (Thanks CougarGT!) That I will be using the heads from. Now, I will be doing my own minor port/polish work to the heads. Yes, I could see better results letting someone with lots of R&D time and more experience do the work, but that isnt as much fun. So here it goes. Any advice from experienced people would be fantastic!

Ok, on the intake side, the top of the runners have a nice "bump" about 3/4 of an inch in. I was planning on smoothing that out as it approaches the bowl. Any probs with this? Also the secondary side runners have a heck of a lot of oil/carbon buildup. If people think that their LIMs are bad after 80k miles or whatever, i cant imagine what these look like (im working with an engine that has approx 37k?). Would leaving the primary runners final smoothness with 80 grit rolls, and then actually polishing the secondary side runners be benificial in preventing buildup on the walls/valves? Is there anything else I can do to prevent this? I am of the understanding that you dont want to fully polish the intake side, but there are lots of people who know a LOT more than me or the people I learned from, hehehe. Any other advice on the intake side would be awsome.

OK, on to the exhaust side. Now, here is where I really dont know whats best. I know everything will be well polished, but how much porting should actually be done? The runner design seems fairly adaquite, although rather rough. The big question is, as the exhaust runners end the ports taper in just prior to entering the headers. Is this wise to remove? I understand that it would improve overall flow, but isn't that there to help reflect exhaust gas pulses? I figured if worse comes to worse, ill just leave that there, but Im really lost on this one.

Anyway, if I completely screw up, I'll sure figure out what not to do next time. Thats what spares are for I guess :biggrin:
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