I've got my engine out right now so I thought I'd port and polish my intake mani while it's out. I'm almost done at this point. But ....
I was chatting with a good friend this weekend from DSMTalk and he was telling me I should leave some of the "rough" stuff inside the runners b/c the turbulence it causes in the air flow allows the fuel to mix more completely at the spark plug and thus create a better combustion. Although it makes sense to a degree, I was wondering what you guys think or whether anyone here has ever heard that before

1999 Eclipse GST 4G63

I think when they mean "not smooth" is not like polished finish. I don't know the technical terms, but when there is just enough roughness, the air and the gas mixes better. So as long as it's not like mirror finish, it should be fine.

1995 Eclipse RS

Take out the injector humps IMO. =)

Your friend would be correct if he was talking about carbuerated (sp)engines. The roughness helps to stir the mixture a little better for a more consistant burn. But on fuel injected engines you want the air to get in and out of the cylinder as easily as possible. The fuel and air come in contact with each other at the end of the runner so I don't see what negative effect smoothing out (polishing) the intake would produce.

I'm polishing a spare intake right now. When I've got it on the car I'll be able to answer this better. I've read some posts about inaccurate recommendations lately. If I'm wrong let me know. tia

I've had my mani on and off atleast 3 times. Each time I tryed something new. The best thing so far IMO would be removing the humps. Its just a guesstimate but i bet they block about 25-30 percent of the airflow. I'll mic it one day and get some #'s.

rough that bitch up - got a grinder - DIE prefereably but kn0obs can use the dremel, it will just take longer then smooth it out with some 100 after

*Skrilla
"Honest officer, I thought you were trying to race me"
Talon: 1st 2.4L
'97 Prelude
'04 350Z

Originally posted by etx
Good luck man! Project 'STFU Brian your talon is dead meat' should be on it's feet soon!

Well, like I said, I'm almost done at this point so I'm sticking with what I've got done. Besides, patting myself on the back I think I've done a pretty good job. It's going to be hard to tell a difference though for me b/c with my engine out all the other things I'm doing it's going to be hard to know what's contributing to what. But I appreciate your responses. I'm going to keep grinding

1999 Eclipse GST 4G63