turbo plenum porting?

[charlief1]

Man you guys are pic happy. :biggrin: I'll give it a shot when I get a chance. The car was modified with mostly OEM stuff anyway. My only fabs were in the exhaust, interior cab, (Pontiac headliner and custom dash pods), and body, (just a GN spoiler). And yeah....it's all black, (don't spank me).

Charlie's been trying to get me to do a sig with all the traditional mods I put into it but I have'nt gotten around to it.

In the spring I'm pulling off the heads and having the valve guides rebuilt with bronze ones. Just waiting on my Uncle Sam check to get me through it.

LOL You know the minute you post a pic Jesse will download it for his "privite time" don't you.:biggrin: LOL

 

[charlief1]

Yep it is an '83 intake. What year plenum you have? Is it the '83 or the earlier coolant filled one?

I've got both Freddie. I haven't modified the 83 yet though because it's still on the car. I'll be taking it off as soon as the turbo is put back together so I can make sure to fit everything up right.

 

[mikemcvaney]

charlie did most of the work at the bottom there was abig ridge athe turbo flange blrdedit and deburred the rest but will going futher help

 

[mikemcvaney]

any porting will help in this area. but nuthing i would worry about until you begin pushing the 12s. and even then, a 1 inch spacer clears up any problems the were present

so it looks good. but most of us arent fast enough to feel change.

A.j.

A.J. a tenth of a second cheated ten times is a second

 

[mikemcvaney]

I had the plenum off mine once. DIdn't really look that bad to me. They crack easily so I don't know if I'd be too excited about doing a whole lot to them. If it's already on your car I would leave it.

have several of them doing this to a back up. Ihave acomplete turbo motor laying around -intake

 

[charlief1]

charlie did most of the work at the bottom there was abig ridge athe turbo flange blrdedit and deburred the rest but will going futher help

A.J. a tenth of a second cheated ten times is a second

Had a few beers tonight Mike? LOL

I think I understood your question. The turbo and the plenum don't match up perfectly and the V6 plenum has a machined ridge on it that's bigger than the opening of the turbo so you need to have the inducer housing machined at an angel to make for a better opening. Then you need to blend the plenums throat to get rid of some of the ridge and open it up some.

 

[mikemcvaney]

I did this back in 11/2006 with my plenum. I don't have any before or after stats. It just seemed to be the thing to do if it's off the vehicle. No problems to this day with the fuel delivery. But I really don't know if it was beneficial, (it looks good though ).

nice work why the bigger hole in intake?Mike

 

[Freddie's Buick]

Is porting and polishing the turbo plenum good for any power gains or will it simply cause the gas to puddle under the carb? Mike

I'd say go ahead and port it. Especially if it's off of the car. Puddling happens to any car if you're too heavy on the throttle or if the choke is problematic.
Nice job on that ride dude. As well as you did the work on your ride you'd probably be able to polish any aluminum part once you get the proper cutting paste and buffers. :biggrin:

 

[Freddie's Buick]

nice work why the bigger hole in intake?Mike

That's the exhaust flange opening. Instead of using coolant to warm up the plenum, the '83 used exhaust heat to heat it up. There's a thin metal hose that attaches from the intake to the front of the plenum that's not in the pic.

 

[mikemcvaney]

I'd say go ahead and port it. Especially if it's off of the car. Puddling happens to any car if you're too heavy on the throttle or if the choke is problematic.
Nice job on that ride dude. As well as you did the work on your ride you'd probably be able to polish any aluminum part once you get the proper cutting paste and buffers. :biggrin:

just got done polishing a1969 triumph bonneville chopper motor every single piece of aluminum been polishing for years.Mike

 

[usetaboost]

LOL You know the minute you post a pic Jesse will download it for his "privite time" don't you.:biggrin: LOL

Oh hell I'd rather see it with my hands than look at it

 

[charlief1]

just got done polishing a1969 triumph bonneville chopper motor every single piece of aluminum been polishing for years.Mike

I know that was a pain to say the least Mike. I've done my fair share of polishing metal myself and the fins are the biggest pain.

Oh hell I'd rather see it with my hands than look at it

Yea sure Jesse. Are you sure that's what you're doing with your hands.:tongue::biggrin: LOL

 

[MNcarbturbo]

How much is included to the exhaust heated plenum? I was going to stick an 83 turbo on my 80 setup thats water heated. The only time I see the heated plenum making a difference is when the motor is hot and it is only needed when the engine is cold. Keep the water heated one or go with the exhaust one?

I have kinda wondered this, theres the manifold heat duct into intake, heated plenum, a HOT manifold and a little flapper that sits on the left exhaust manifold to push exhaust into the intake and I have 2 of the 4 and the thing runs fine in the cold except for startup. Does half this stuff even help drivability?

 

[charlief1]

How much is included to the exhaust heated plenum? I was going to stick an 83 turbo on my 80 setup thats water heated. The only time I see the heated plenum making a difference is when the motor is hot and it is only needed when the engine is cold. Keep the water heated one or go with the exhaust one?

I have kinda wondered this, theres the manifold heat duct into intake, heated plenum, a HOT manifold and a little flapper that sits on the left exhaust manifold to push exhaust into the intake and I have 2 of the 4 and the thing runs fine in the cold except for startup. Does half this stuff even help drivability?

There's no difference in the turbo, just the plenum. If you don't have the 83 plenum and intake it won't work. The turbo will though.

The flapper you're talking about isn't for exhaust but for heated air off the exhaust manifold for cold start up. It's linked to the intake hose. These cars originally had a heated plate under the carb to help with cold starts and warm up the air fuel mix to help.

 

[MNcarbturbo]

So an 80 plenum bolts to an 83 tubo no problem?

I know theres that exhaust manifold heater into the intake tube but there was also a flapper bolted to the drivers exhaust manifold outlet that would close when cold and force the exhaust gas into the EGR or into the intake or something.

 

[charlief1]

So an 80 plenum bolts to an 83 tubo no problem?

I know theres that exhaust manifold heater into the intake tube but there was also a flapper bolted to the drivers exhaust manifold outlet that would close when cold and force the exhaust gas into the EGR or into the intake or something.

The turbo will bolt up without any issues.

As far as the flapper in the manifold, my bad. It's supposed to heat up the manifold faster by making the exhaust go through the intake to the other side instead of the exhaust directly. Cut the flapper off and forget it. They suck big time and can cause det issues if everything isn't working right.

 

[usetaboost]

WHen I replaced my driver's side manifold with a crack free one, the flapper was actually broke off. It was lying inside the crossover corking it up. Even before I put a brand new turbo and actuator on it, it would still turn the one tire over when I punched it. It was kinda fun going stoplight to stoplight with it every once in a while

 

[dr_frankenstein]

the early manifolds are a real pain to get all organized though.

cross overs that belong to the early cast stuff.... then cross overs that belong with the newer set.

in the end.... the 84/85 is a great upgrade.

consider it.

A.j.

 

[FlintBuick4Life]

I ported mine a little... nothing major, just cleaned up some crappy molding that the factory did... GM was too lazy to do it back in the 70`s I haven't finished it yet, like others have said, its way too time consuming and I get really board after spending a couple of hours grinding and sanding Aluminum:biggrin:

 

[MNcarbturbo]

Kinda on the topic of exhaust manifolds.

My cast set is heavy and ugly and it leaks at the passenger side crossover tube. Fabrication isnt a big deal for me so I was thinking of taking a set of 86/87 headers and cut the passenger header at the #4 cylinder and build a new pipe going up instead of to the front like stock. I mean they are proven into the 10's. Do they flow better than the 84/85 enough that it would make a difference for a C/T setup?