Porting/Polishing
 

I was seeing a lot of stuff on nasioc about porting the exhaust manifolds. Is there a place in town that does it cheap or is it best to diy. I have experience with metal working and all that business, ive just never ported or polished before. Has anyone here done it? Tips, links, emoticons? :eek:

Frankly, in my opinion, the only way to learn how to port is trial and error. Lots of error. It's always been suggested that the first part you ever try to port should NOT be one that you need. Most old hot-rod guys I know would go get some junk heads/manifolds from a yard and practice on them, just to avoid F*ing up something they need to use. It's always surprising how fast metal comes off a part when you shove a spinning carbide bit into it!


My emoticon is this :twisted: ...it's my favorite!

I ported my Turbo and Exhaust Manifold. Make sure you have a good bit and a BIG air tank. Don't even think about Dremel. My old Talon did pull stronger and longer after the port job but no real prove from Dyno.

I just want to know if its worth my time doing it. And im mainly talking about the exhaust manifold. I dont wanna touch this stock turbo because im just gonna swap it out later anyways.

I don't know what class you plan to run in at autocross, but porting/polishing the wrong thing can end you up in Street Mod, if that's something you care about. ;)

What class would I run in currently,
Cobb AP stage 2
3" TBE, no cats, gutted uppipe
intercooler y-pipe kit.

I would like to run at the top of a very low class. As in wrestling I would rather be 205 in the 175-205* class instead of a 206 in the 206-245* class. Ya feel me?



*not real weight class.

No brake/suspension mods? Stock wheels?

Sounds like ESP to me.

ESP unless there are other mods like ALK or brake caliper changes or something that would bump to SM. And porting anything other than the manifolds is not legal except in SM or higher.

If you can replace the headers in ESP, why can't you port them?

Stock wheels but the owner before me put slotted/drilled rotors on it.

Rotors are fine as long as they're stock dimensions.

Reading the rule book yourself is the easiest way to find all this out:

http://www.scca.com/_FileLibrary/File/2007SoloRules.pdf

Ninja edit FTW.

Huh? I didn't edit anything.

You said porting *anything* is illegal in all classes but SM and up... but you can certainly port anything that's legally replaceable. IIRC, SP lets you replace exhaust components including the headers, so why would 100%'s wish to port his exhaust manifold be illegal?

Edit: I get it... you ninja edited... n/m. :lol: Oh an BTW, I don't think porting the intake manifold is legal in SP... just the exhaust.

Intake mani is legal to replace in SP. I think it's to simplify the engine update/backdating issue. I know I'd much rather be able to replace cams than intake manifolds, but I suppose flat 4 guys might be in the minority there.

should you decide to do the porting, spend the extra money on a good carbide bit. single cut for aluminum and other soft and/or non ferrous material. double cut for ferrous stainless, and other hard materials(yes use this one). dip the bit in oil for cooling (cutting fluid or motor oil, i use motor oil because cost). i have a "tungsten/carbide" cutting bit, and it seems ok. so if you have a choice, i wouldn't pay more for the added tungsten. usually your local weld shop will carry good stuff. or if you must save a few pennys, try these:this is what grainger has to offer and this is what enco has to offer