Hi all,

I've just started porting my plenum. It's the first time I've ported anything ever and I'd like some feedback on what I've done so far. So, without further hesitation, here's the throttle body!

BTW, I think you mean plenum. What you have done is exactly what it should look like. You have removed the bottom obstructions in the opening of your plenum. Now you can touch up the side walls too. Just be careful, as these areas are easy to "break through" with the porting. The last thing you want is a hole through the outside.

I dont know how true it is, but, I was told that a stock 48 mm TB with the porting you have done, will flow more than an aftermarket 52 mm bolted up with NO porting. In a way it makes sense.

I just noticed, "right hand drive" in your sig. COOL! Whats the speed limit in New Zealand?

I ported my pleium, throttle body openings, the egr walls, then gasket matched pleium. I also gasket matched my runners and removed those little rings around inside of the runners, I also ported my base gasket matched. where it mates with the heads and where the runners meet with the base. Wow it took maybe 50 hours pulling it off porting cleaning and painting. but my results where GREAT. I just fired it up two three days ago. I had to reburn my chip thats about it. Runs like a champ. i'll have pictures of it all soon

Originally posted by brutalform
BTW, I think you mean plenum.

Oops. Yeah, the throttle body openings on the plenum.

What you have done is exactly what it should look like. You have removed the bottom obstructions in the opening of your plenum.

Sweet, this is just what I wanted someone to tell me.

Now you can touch up the side walls too. Just be careful, as these areas are easy to "break through" with the porting. The last thing you want is a hole through the outside.

You're not wrong there, question is, how much can you grind down? Is there a measurable amount you can safely remove, or are GM production standards so inaccurate that each case is different? I am indeed afraid of grinding too far and making a hole.

I dont know how true it is, but, I was told that a stock 48 mm TB with the porting you have done, will flow more than an aftermarket 52 mm bolted up with NO porting. In a way it makes sense.

Yeah it does make sense.

I just noticed, "right hand drive" in your sig. COOL! Whats the speed limit in New Zealand?

Not fast enough. Actually it's 100km/hr or in your terms, 60MPH on the highway.

Does anyone know how much I can safely take off the side walls at the front of the plenum?

I wouldn't go super thin. Keep checking the thinkness with your figures and leave good amount of matrial. I went to thin and put a little hole through my pluiem but JB weld fixed it right up.

OK cool, thanks for that.

On my plenum I had the area welded up on the outside at the angle where the throttle body mount and the rest of the plenum meets. I was able to do a lot of grinding in that area because of it. I also blended the welds in to make it look factory. Allen

Yeah i wish i would have thought about getting some weld sticks, they are not that costly and look much better. Oh well its on the passageer side so it's harder to tell.

Another key clue when porting aluminum.

If the pitch of the cutting device changes, ie. it will get very shrill and whiney when your almost thru.

If you hear this sound stop immediately. Its letting u know your about 2 seconds from going thru it.

later
Jeremy

Well, I've made some progress on the porting and I believe I've finished. What do you guys think of this?

And this one...

Good work man, The throttle body opening i went out I think I think 2 1/4 i used a drum sander to it. made sure it fit in the hole and it made it nice and round i went i little larger then need just in case i deside to get a 58 mm throttle body.

So are you doing the base too? The runners can use a little help the base needs help as well too. you no while your in there kinda thing.

I said i'd post my pictures, well there larger the 1mb so it's a f'ing pain in the but to shrink them down. if you want i can email you a couple pictures of my work.

later

Originally posted by 8UpAFord
Good work man, The throttle body opening i went out I think I think 2 1/4 i used a drum sander to it. made sure it fit in the hole and it made it nice and round i went i little larger then need just in case i deside to get a 58 mm throttle body.

So are you doing the base too? The runners can use a little help the base needs help as well too. you no while your in there kinda thing.

Cheers dude, nice to know that I did it right, cos it's the first time I've ported anything. I will do the base as well but it's bolted to the block at the moment. I've also done work on the runners - I removed the wee lip that's inside them so it's all smooth.

I said i'd post my pictures, well there larger the 1mb so it's a f'ing pain in the but to shrink them down. if you want i can email you a couple pictures of my work.

Yeah that would be cool if you could do that. I presume you have a PC with Windows on it, but I wouldn't have thought shrinking the pics would be too hard. If you send them to me I could shrink them for you.

Cool man that would be nice. Whats your email addy? I'll send then tomoorw. There not the greatest pictures but they pass the test i guess.

You've got a PM.

Sorry not sure about what a PM is?

PM is Personal Message. I sent you one yesterday.