I'm not talking about port matching, I'm talking about cutting it open and smoothing the runners, opening the runners up a little at the opening and making a nice/smooth taper, cleaning it up internally, nothing too drastic, and then welding it back together.

I have done mild port work before on fords and don't intend to hog this thing out.

has anyone done this? anyone care to guess how much a mild port job would be worth on a itr intake manifold on a ls vtec with some mild cams?

if anyone has pics that would be appreciated too!

 

I have done it without cutting the manifold open, they make a porting tool to get up inside the runners.

 

I'm about to start this week on my intake mani cutting/porting/welding project

 

I've done several.

 

I have done it on my H series intake, thankfully it unbolts H series FTMFW!!!

 

I was thinking about doing this as well but I thought your not suppose to polish the runners because the fuel won't atomize as good?

 

You'll notice that the injectors are actually at the bottom of the runners so there's no "atomization" to worry about before hand.

 

anyone have any dyno sheets or anything? how about some pics for the noob?!


also, what tool are you talking about that gets up in the runners? you mean like a flexi shaft or do you mean just using a super long bit to reach up in there. Would certainly be best if I didn't have to cut this thing open....

 

like these, then use a cartridge roll and clean it up

http://images.google.com/imgres?imgu...26tbs%3Disch:1

 

its pretty easy to do but you need a long shank for the cartridge rolls, it takes a lot of time though theres a lot of material

 

Cutting an aluminum intake open then welding it back together is quite an intense aproach to smoothing out your intake. The long shank grinding bits & alot of patience is prob. the best route. Im not questioning your welding ability but you might aswell fab up a sheetmetal piece it would prob be easier to get right. & you wouldnt risk ruining an intake . Just my .02

 

I ported mine about a year ago. I don't claim to be a professional. I just enjoy tinkering with stuff.
I cut open the top of the plenum and then opened up the plenum to runner area.
I used a flapper wheel and a dremel. Make sure you use a mask, the last thing you want it to breath in aluminum particles.

When i was done i had my brother weld the top on, and then we bored the TB opening to 68mm. Originally i cut the runners but that is unnecessary if you cut open the top as you can get to the top of runners through the open plenum area.






Here is a pic of the flapper wheel. They make 80 and 120 grit.

 

You mean like this.

 

http://www.d-series.org/forums/engin...cs-inside.html

 

I'm going to be doing mine fairly soon and will be doing before and after dyno tests.

 

Im convinced ill be doing this now aswell . Thanks for the insight everyone. And good luck neverstop post some pics of the progress.

 

hey doc, thanks for postin the link. Now i dont have to post the pics lol

 

As was pointed out, the injectors are after most of the runner. You are probably thinking about promoting laminar flow by establishing a boundary layer. I generally finish the runners to an 80-120 grit finish instead of a true polish for this reason.

 

AWESOME guys, thanks for the pics and help.

MAR: is that a before and after dyno test? looks like pretty much 1-2hp gains?


I will be just putting this Type R manifold I got on my motor with the 68mm tb for now but then I plan to get some mild cams and spray a 50-75 shot on it by the end of the year and I'll port the manifold when I pull it off to plumb the direct port nitrous. I'll be sure to post pics though, that is awesome everyone is so cool to share here.

 

This thread inspired me to cut open my b18a intake manifold, I will be porting soon. I didn't realise how thin the metal is! I already see bad casting marks inbetween the runners and a bunch of lumps I can grind.

 

awesome man! be sure to share with us how it goes!

 

I don't cut and weld mine

 

nice work. you'd see much better gains doing the plenum than just the runners

 

NICE. great pics, I think I'll probably end up cutting mine open though so that I can taper the runners and clean up the entry of the runners to the ports.

Anyone think a well done, home ported B16 intake manifold would put up similar numbers to an itr or blox im?

 

[QUOTE=00b18b;41956012]I don't cut and weld mine


QUOTE]
What kind of manifold is that?