Looking to Port and polish my exhaust mani to clean it up/get it flowing a little better. Anyone have any suggestions?
What should I use to p&p?
- Thread starter 1_slo_92
- Start date
what do you mean? like what kind of tool? you use a rotory bur/carbide cutter with a die grinder. maybe you need to do some reading before you get into this:
How to build and modify Chevrolet Small-Block V-8 cylinder Heads
By David Vizard
*Gets the nomex* i know its a SBC book but the techniques and info are universally applicable. just try and find a book on porting the 7m.
How to build and modify Chevrolet Small-Block V-8 cylinder Heads
By David Vizard
*Gets the nomex* i know its a SBC book but the techniques and info are universally applicable. just try and find a book on porting the 7m.
if you do anything to the head, don't port match it, keep the exhaust port smaller than the hole on the exhaust mani.
taken from DIY -Basic Cylinder Head Porting:
In most cases, you never port match the exhausts. Many stock exhaust manifolds and virtually all tube headers will have larger port sizes than do the heads. You want that "step" from the port to the larger header tube or exhaust manifold because, as pressure pulses flow back and forth in the exhaust system, it acts as a "reversion dam" by resisting back flow of exhaust gases into the port. If you end up with the rare situation where the stock exhaust manifold has ports smaller than those in the head, you will need to port match. Use the same technique used to match the intakes.
In most cases, you never port match the exhausts. Many stock exhaust manifolds and virtually all tube headers will have larger port sizes than do the heads. You want that "step" from the port to the larger header tube or exhaust manifold because, as pressure pulses flow back and forth in the exhaust system, it acts as a "reversion dam" by resisting back flow of exhaust gases into the port. If you end up with the rare situation where the stock exhaust manifold has ports smaller than those in the head, you will need to port match. Use the same technique used to match the intakes.
well ok just to clean out the carbon build up from the years any suggestions? I was thinking if someone made long skinny wire brush (almost like a pipe cleaner but a wire brush) that I could hook to my drill to clean it up, or I can have it sand blasted right?
NewWestSupras said:
my bad. i mis read the other post. i thought it said keep the manifold hole smaller than the port, which would make no sence.