thanks

I searched it under porting and got 18 different items.

WADAD

 

Summit Racing Equipment- Porting Kit: part # SAI-260001 $39.88
I also purchased a 10 pack of Cross Buffs: part # SAI-265024 $11.69 The manufacturer for these items is Standard Abrasives.
7rider, no plans yet to work on my cyl head.
Dangerous, Port & Polishing an intake manifold means enlarging the ports on your intake manifold to better match the size of the ports on your cylinder heads to achieve a more larger and "graceful" airflow from your intake thru to your cylinder head intake ports. During this modification one also smoothes out any sharp angles and irregularities caused during line production of a manifold. Then the finishing touch is polishing the areas you modified, down to approx 3 or 4 " into the runners. As Wadadlig alluded to, one shouldn't polish too far into the runners or the manifold plenum because you need a slightly rough texture on the inside to keep a dense air charge moving fast. This was more important in the old days when we used carburetors and had air/fuel mixtures flowing thru the manifold but modern engines (like the Mivec) have only air flowing thru and the fuel is injected into the airstream just before it enters the cylinder head so it isn't as important but I'm still mindful of it ( thanks, WAD). This all works in conjunction with the "P&P" I'm going to do to my TB. Your goal is to get alot of cool clean air from your intake filter straight thru into your cylinders. I'll certainly let everyone know how it turns out.

 

so you are doing the throttle body too? how different is this or is it different at all? sounds like I need to buy a few things in Dec to make my car enjoy the winter air more

 

plz post the results soon, i plan on doing this soon and i would like to know what the gains feel like.

 

I'll caution you on the TB. On most TBs and carbs the opening is not perfectly round. That's not really the problem, fitting the butterfly is. It not only has to fit the hole, it has to be tapered to fit the fluting of the TB. If the butterfly doesn't have a nearly perfect seal you'll run into all kinds of problems, the least of which is that your RPMs will raise, as your engine thinks you're at part throttle all the time. Worst a badly matching butterfly acts like a vacuum leak and you can't keep the engine started.

If you're a machinist with experience, that's excellent. In fact, let me know how much you'd charge to bore out and then fab a butterfly. I have a spare G94 TB that I can't get rid of since it's stock.

 

Alchemist, thanks for the tip but I'm not going to touch the butterfly landing as that would be a total bore job. I don't plan to change the diameter of the throttle plate (butterfly), just a little "knife edging" to it & streamline the cross shaft and bolts. Then a little radiusing and polishing of the forward and rear approaches. I've researched that one can gain some pretty good flow improvements by doing so. But I hear ya about TB's causing problematic idling, vacuum leaks,sensor malfunctions, etc. No, I'm not a machinist just an old mechanic but I have done similar jobs on a few carbs & intakes in my day.

 

awesome. I've seen several folks who think they can make a 55mm TB a 60mm TB with just a dremel and a sanding cylinder, so I'm always on the lookout for people who want to blow up their engines while trying to save a buck.

good luck!

 

Dangerous, working on the TB is a little different but uses the same tools plus maybe a Dremel tool for the finer work on the cross shaft & "butterfly".
candy, I'll post results for sure.
I think I better say a WARNING here. I didn't start this thread to encourage everyone to do the same as I am. As I said before, this is DEFINITELY NOT a job for the uninitiated!! Not considering the complexity of removing the intake manifold, Porting & Polishing should be done by a semi-knowledgeable person with the correct tools. Cause if you do it wrong, you can screw up your whole manifold, possibly affecting other engine systems as well. And I don't have to tell you how much a new manifold costs! But if you're pretty handy with a wrench and have the time & tools, by all means feel free to do this mod. Or you can buy RRM's P&P Manifold.

 

Here are pics of the finished manifold and before & after shots of the stock throttle body flow modifications: radiused air funnel, thinned TB plate cross bar, "knife-edged" throttle plate. The white gaskets are the phenolic gaskets from PR-Mivec.

 

Standard Abrasives Port & Polish Kit sold by Summit did an excellent job, a very complete kit. I used a standard 3/8" variable drill and then a Dremel with various attachments to do the finer work on the TB.

 

looks great!

 

What was the max speed on your drill?

I've been looking at what type of tool I want to do this with since I now have my manifold in hand. Dremel or drill?

WADAD

 

Thanks again, PR. Hey, I've been meaning to ask you, how did you manage to squeeze 215hp out of your Mivec? Tell me some secrets!!

 

And yes your porting work looks really "clean"

WADAD

 

WADAD, I just used an everyday Black & Decker variable speed drill. I think max is 2250 rpm on it. The bits from the P&P kit only fit the 3/8" drill. It's more than enough to do your intake manifold and radiusing your TB air funnel to create more of a venturi effect. Notice I didn't say "boring" your TB, just slight mods to increase the flow & velocity. The finer work on the TB should be done with a Dremel. I also bought the long flexible shaft attachment to make it easier to work in the TB throat.