is there any gain in porting the upper and lower intake manifold on a 13bt? if so where in the power ban.my friend was saying it will get u more top end but less bottom end.is this true or is he a idiot

 

I think it'll boost your power all around. I used some carb cleaner on the upper and lower manifolds and it idled and ran smoother. I would imagine porting would boost power pretty well. Donno if there is any downside though. Also, I don't know where would be the best place to port. You can't really port the inside of the manifold and porting the opening ends may cause intake leak bc the gaskets probably won't seal tight anymore. Intake leak would suck... Buying a new set of manifolds would be $$.

 

All of the manifold gaskets are like $25 from a Mazda dealer. Use those as your template, and port about an inch in. I have heard of gains of like 10 hp at the wheels from doing this. The downside:It takes about a weekend to do this, and it is a BITCH to get all of the vaccuum hoses back on correctly. Good luck!!

 

or you can send them to http://extrudehone.com/automotiveoem.html

 

or not

 

I have sent mine to extrudehone plus a bigger throttle body. As soon as i put everything togather i will let you know for any difference. It will take me sometime since i am rebuilting the whole car