Cleaning the plenum
- 91_Red_GTZ
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Cleaning the plenum
Any tips or tricks on cleaning the oxidation off of plenum? I have tried many different cleaning solutions/fine sandpapers/ fine wire brushes, but nothing is really giving me the results I want. Is there any other products that I could use or am I just going to have to stick with time and the good old elbow grease?
Also, what would be the best to polish it with?

Also, what would be the best to polish it with?
1991 Beretta GTZ, 3.1 V6 - 3 Speed A/T


- Money pit Beretta
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Re: Cleaning the plenum
It looks good right now. I think I used a green 3M pad to clean of my 3400 intake, but it was not as old(it's a 2000). As for polish it's better to leave the ruff coating. If your talking about the smooth spots a good mag wheel polish will work.
keep'em flying!
- 91_Red_GTZ
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- Money pit Beretta
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Re: Cleaning the plenum
You welcome, hope that pad does the job for you. By the way if I didn't say it before I like your car. It looks to be in very good shape. I had a 90GT that I miss alot and it's good to see an older car.
keep'em flying!
- 91_Red_GTZ
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Re: Cleaning the plenum
If everything goes the way I want it to, Ill have everything all polished up and looking nice to go to my very first Bfest.
1991 Beretta GTZ, 3.1 V6 - 3 Speed A/T


- Money pit Beretta
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Re: Cleaning the plenum
Cool man. I still have hope that I can make it to one someday. Post some pics of the intake after you get it done. Or some close ups if the 3M pad doesn't help. I can tell you I did have to work hard to get that stuff off.
keep'em flying!
- 91_Red_GTZ
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Re: Cleaning the plenum
Will do. I plan on painting the edges of it red when I am finished with it, I hope that it will come out looking as nice as this one.
http://carphotos.cardomain.com/ride_ima ... _large.jpg
http://carphotos.cardomain.com/ride_ima ... _large.jpg
1991 Beretta GTZ, 3.1 V6 - 3 Speed A/T


- Money pit Beretta
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Re: Cleaning the plenum
Wow! That would take more than just polish. You would need some buffs to do that kind of thing after some sanding. Looks like that guy got lucky and found one of the rare 3.1 turbos.
keep'em flying!
- 91_Red_GTZ
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Re: Cleaning the plenum
Yup yup he did. I worked on my today for about an hour, scrubbed most of the stuff off with one of those 3M pads and some super clean. Just started wet sanding, probably gonna work on it some more tomorrow and start to buff and polish. I'm probably gonna just remove it and set it on a table so its easier to work. I didn't want to remove it because its been off alot and idk if the gasket will hold up much longer. But I'm hopefully gonna pull the motor this weekend to put a bigger cam in it (I don't really want to cut a hole in the side of the fender wall). I got like 5 different things that I want to do to it and I don't know what to prioritize.
1991 Beretta GTZ, 3.1 V6 - 3 Speed A/T


- Money pit Beretta
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Re: Cleaning the plenum
I hope that 3M did the trick. I used if more for the ruff areas because I didn't want to hurt it too much and the 3400 intake doesn't have those flat spots on it. I'm out of time so I have to cut this short. When you have the engine out be sure to do the lower intake gaskets. Please tell me that you have a cam and lifter kit. Also you can put some 1.6 rockers on, but you would need to put some new stem seals on. Try to PM 1988GTU and see if he can get some for you. If it was me I'd put new guides in the heads, but that would be me. Keep an eye on your oil pressure. The oil pump drive can go out. New push rods would be good also. What cam did you get?
keep'em flying!
- 91_Red_GTZ
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Re: Cleaning the plenum
Maybe I won't be putting it in this weekend : ( lol. I might just start saving up and getting all the parts and put it all together over a weekend or so (That way I won't have to keep tearing it apart.)
1991 Beretta GTZ, 3.1 V6 - 3 Speed A/T


- Money pit Beretta
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Re: Cleaning the plenum
http://www.competitionproducts.com/sear ... er=1&val=0
That link is for some rebuilt heads. If you look down the list you can get the heads that you have or the newer D port heads. With the D ports you would have to get the newer exhaust manifolds and a new down pipe. Those manifolds flow a hell of alot better than yours. I'm not sure if the EGR pipe would need to be changed. Just something to think about. Oh and ask the company what parts they use and ask here if they are any good. From what I hear they are close to GM parts, but not as good. The price is very low though.
That link is for some rebuilt heads. If you look down the list you can get the heads that you have or the newer D port heads. With the D ports you would have to get the newer exhaust manifolds and a new down pipe. Those manifolds flow a hell of alot better than yours. I'm not sure if the EGR pipe would need to be changed. Just something to think about. Oh and ask the company what parts they use and ask here if they are any good. From what I hear they are close to GM parts, but not as good. The price is very low though.
keep'em flying!
- 91_Red_GTZ
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Re: Cleaning the plenum
I got the intake all cleaned up now... I can actually see myself in the reflection. 3M pads worked pretty good for removing most of the build up. After I got most of the oxidation off, I started to wet sand with 320 grit sand paper. When I finished sanding, I hand polished it with some Mothers Mag & Aluminum polish (or something along those lines). It turned out really nice, I'll post some pics and check into those parts, thanks for site.
1991 Beretta GTZ, 3.1 V6 - 3 Speed A/T


- Money pit Beretta
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- 91_Red_GTZ
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Re: Cleaning the plenum
Sorry about that. The site was down or something. But here they are, still doing some more polishing, idk why, I think it looks pretty good but I don't have anything better to do(lol). Was thinking about doing the same thing to the alternator, but I stopped because it would be just my luck that as soon as I get it finished, it would seize up or something along those lines.
Oh, and the lighting is not that great, I have a flash on my phone and I had an light hanging from my hood. It looks alot better in person.
Oh, and the lighting is not that great, I have a flash on my phone and I had an light hanging from my hood. It looks alot better in person.
1991 Beretta GTZ, 3.1 V6 - 3 Speed A/T

