Has anyone tried polishing the internals of a manifold to get a little more performance?.. Is it worth it?

Thanks in advance.
--D

 

ohh, let me clarify a bit.

My 94runner "putt-putt" is out getting a valve job as we speak. Can anyone think of mods that I can get done while it is in the shop in order to take advantage of its dissasembled state?.

Polishing the manifold was one of the things I had thought of.

 

Porting the inside of say a throttle body and upper intake manifold yields little results. My buddy ported out throttle bodies and manifolds and people thought it helped throttle response and the car felt more "snappy."

Porting the intake and extruding the manifold should help with airflow. Polishing the lower intake manifold near the injectors is not wise since it'll reduce atomization of fuel. You want a bit of roughness in the tract for slight turbalence and atomization.

J

 

I have a bored throttle body as well as a ported and polished intake and plenum. I am very happy with the results and I would recomend it to anyone. I experienced substantial gains througout the entire rpm curve. Because of the port and polish, my 4Runner has an impressive power surge between 3200 and 5300 rpm. (it just takes off when it hits 3200). I would also recomend getting headers if you decide to go with the port and polish because all that extra air will need a place to go and the stock exhaust manifolds just won't cut it.

 

while its torn apart have them leave the exhaust crossover pipe out. Have them weld covers over the cross over openings then run a stick of 2.5 exh. down and meet up near the transfer case. Theres some more flow. Or just get headers.