Port and Polish

jshankcj7

Hey all you AMC guys I've got a question. Ive got myself a 1974 304 and I've just bought a pair of reman. heads with a three angle valve job and new valves/springs etc. My question is would I be able to do a port and polish job on these myself with the help of my dremel tool? If thats not a good idea how much might it cost for these to be done professionally and what kind of horse gains could I expect? Thanks, I appreciate your input, J.Shank

jeepsr4ever

IT really isnt a good idea to start porting with a dremel. Even with a die grinder your still porting in the dark without a flowbench. You can actually hurt the flow of your heads. For a 304CI motor it all depends on the rpm it will see. You can expect to pay 600-1600 for a good port job. If this is a street motor expect to pay less of course and a competant machinist will ask you what rpm your running and what kind of camshaft. Some build their camshaft off the final head flow numbers and some go as far as tailoring their rocker ratios different to get that magical 92% intake to exhaust efficiency rating. What is your application?

jshankcj7

its gonna be seein in the 1500-4000 range mostly trail riding in low rpms and some high in the mud. Its in my jeep CJ7, Im still learning quite abit about AMC's and engines overall. I'm gonna be installing an RV cam in this that comes with my rebuild kit. Not sure of lift/duration. Would this be worth my money to get something like this done or just skip it?

fifesjeep

jshankcj7 wrote
its gonna be seein in the 1500-4000 range mostly trail riding in low rpms and some high in the mud. Its in my jeep CJ7, Im still learning quite abit about AMC's and engines overall. I'm gonna be installing an RV cam in this that comes with my rebuild kit. Not sure of lift/duration. Would this be worth my money to get something like this done or just skip it?

Leave it alone, these stock heads actually flow really well!! Better than what you would expect and seeing that you'll be in the 1500-4000 range most of the time I wouldn't even consider it... You wont notice the difference in that range anyway... (for the most part).

jshankcj7

Thanks for the input, you probably saved me a good deal of money and headache. Thanks, J.Shank