Does anyone do porting and polishing?

[Cornerdealy]

I want to get a upper and lower intake manifold and throttle body from a 3100 ported and polished, and i thought it would be good if i could send it to someone who has worked with w-bodies before to do it, before I get someone locally.

[Cornerdealy]

how much did it cost?

[NOHC_WBody]

but thats a major job only to be trusted to someone whom knows what there doing

 

Definitely. Most of the good engine builders I know like to polish the exhaust side to almost a mirrorlike shine & leave the intake side in more of a matte/slightly rough finish..something about the mixture condensing or some shit on the walls when they're polished a lot.

 

I'm gonna tear the 3.1 that's in the Gutlass right now apart & have the motor rebuilt to drop it into the 88' 5 speed I'm about to buy. Maybe have some shit done to it as well. Probably cam/springs/rocker arms with the intake & exhaust manifolds extrude honed & some basic headwork on it. What did the port matching cost? I'm considering that too.

[Robby1870]

but thats a major job only to be trusted to someone whom knows what there doing

 

Definitely. Most of the good engine builders I know like to polish the exhaust side to almost a mirrorlike shine & leave the intake side in more of a matte/slightly rough finish..something about the mixture condensing or some shit on the walls when they're polished a lot.

 

I'm gonna tear the 3.1 that's in the Gutlass right now apart & have the motor rebuilt to drop it into the 88' 5 speed I'm about to buy. Maybe have some shit done to it as well. Probably cam/springs/rocker arms with the intake & exhaust manifolds extrude honed & some basic headwork on it. What did the port matching cost? I'm considering that too.

 

Yeah, if the intake side is smooth the gas will fall out of the mixture coming in, killing performance. You want the gas atomized for lack of a better word, in the air. But, smooth exhaust ports are desireable

[BIGBULS]

You know that intake porting is of very limited usefulness right (on a $$ per hp scale)?

 

ESPECIALLY when you are only getting stuff gasket matched...........

 

I mean, I doubt you'll see more than 3-4hp from porting both upper and lower IM's AND getting a big-bore TB on a 3.1 or 3100 (*maybe* as much as double that on a 3.4L DOHC....but thats about the upper limit).......

 

 

 

 

If you DO want to do it right (because you are getting a cam that can actually USE the extra airflow), get it all Extrude Honed. It costs roughly the same as buying from RSM, and does a FAR better job (it gets the ENTIRE runner length).