if someone has done it... please share.. thanks

 

do you know what porting is?? it is where you match the port size on the head to the gasket. you dont do it to the manifold. just the head itself. because there is no way to smoothly and effeciently to port the whole manifold.

just get a header if you want better flow.

 

Well there was a famous tuner shop in Torrance, Ca who did port the exhaust manifold just to see if there was any inprovements. On the dyno it showed a max of only 1-2 hp. I think the shop name started with a letter "D"

So to answer your question yes it has a little more improvement but is it worth it? No not for the amount it takes to port the exhaust manifold since the design was never intended to be used for performance purposes.

 

1 or 2 hp is goog enough for me, just need it to be the stock exhaust mani. anyone else done it? thnks

 

what stock mani are you referring too? if its a y8, i read somewhere that enlarging the collector size yielded some gains so you might want to check that out

 

Also remember that the exhaust manifold is cast iron and is much more difficult to port than is an aluminum head. Have you considered using a header, and then welding brackets to it in order to mount the heatshield so it looks just like stock?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by civictildeath &raquo;</TD></TR><TR><TD CLASS="quote">do you know what porting is?? it is where you match the port size on the head to the gasket. you dont do it to the manifold. just the head itself. because there is no way to smoothly and effeciently to port the whole manifold.

just get a header if you want better flow. </TD></TR></TABLE>

Actually, you're wrong. That is port matching, and it can be done on either end, the head or the manifold. And, yes, there is a way to smoothly and efficiently port the entire manifold and it happens all the time.

Now, would porting the OEM manifold help? Not really. Aftermarket exhaust manifolds can be had for pretty cheap. Try looking around the classifieds here or Ebay, of course.