if i were to get a stock N/A lower intake and upper intake and polish the inside like you would do on the outside of the FD intakes would it be better performance?? cause like my dad has all the tools to port n polish so i can sand down the inside with his air tool and then polish it out will i get anything out of this any hp gain at all????
TwEaK

 

You actually want a fine finish, that is not a polished shiny surface for intakes.

They should look like this:

 

and about how much hp gain do i get out of this??? and could you tell me some grit numbers i would have to do to do this kind of job??
TwEaK

 

It's not really HP your getting but better flow which will result in hp.

 

Obviously nobody has dynoed to compare the difference. I have ported the inside of my Turbo manifolds before and the results were barely noticeable. I think you will see a difference in top end and response but probably not a great increase in peak HP#'s.

The ide with porting is to get rid of as much restriction in the manifold as possible giving the air a straighter shot into the engine. Bigger is not always better!! Think Velovcity over Volume and you will probably be alright. As far as Grit goes you will need the Die tools for the air tool then you can finish up with different Grits going from bigger to smaller until it looks the way you want it to.

 

Just cleaning the surfaces up will do jack and ****.

Probably hurt flow, since the as-cast surface is actually pretty good.

The real gains in porting are from *reshaping* the ports.

- Pete ("You can't see the forest for the trees...")

 

ahhhh ok ok i understand..... could i do it all with just different grit sandpaper.... or do i need those metal porting ones??? anyways i dont really want to be reshaping **** this is my first time i just wanna do a nice porting job inside the intakes just to see if there is a difference if there is good if there isnt o well w/e its worth a try neways any links or anything would help greatly...
TwEaK

 

bump

 

Maybe there's something useful in this *thread, although I missed the boat when it comes to porting >https://www.rx7club.com/showthread.p...threadid=79511