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Auto Detailing and AppearanceShare tips and tricks on how to make your Third Gen shine! Get opinions on products or how something tasteful looks on your Chevrolet Camaro or Pontiac Firebird.
Trying to completely restore an L98. Does anyone know a way to restore the intake manifold, runners and plenum back to the original finish? The lower intake is currently painted black and the plenum and runners were glass-beaded and it doesn't look quite right. Trying to stay away from painting.
Also does anyone know if there's a paint to match the original valve covers?
Subscribed. Have the same issue with the intake and also ac / smog pump brackets. Re the Plenum and runners, I am going to try to polish them once I manage to smooth down the surfaces.
Re. the valve covers I am getting them chromed.
So not the exact scope but still interested in comments on how to restore the inlet.
Once aluminum has been glass beaded or sand blasted they won't have the new "as cast look" ever again. (unless you find the 409 guy that resurfaces them $$$$$$)
Once aluminum has been glass beaded or sand blasted they won't have the new "as cast look" ever again. (unless you find the 409 guy that resurfaces them $$$$$$)
Try to find unmolested parts and clean those.
What would you clean it with? I've been wanting to scrub mine as it's all original but dirty. I don't want it to end up looking polished or shiny.
Once aluminum has been glass beaded or sand blasted they won't have the new "as cast look" ever again. (unless you find the 409 guy that resurfaces them $$$$$$)
Try to find unmolested parts and clean those.
Agreed. I have another set of runners that are in good shape. Mainly looking for help with the lower intake and valve covers.
Ok. You tell me which aluminum parts under the hood of my car are painted and which are natural aluminum. I'm guessing you'll get at least a few wrong.
It's not an exact match to anything, but it sure beats permanent stains, corrosion, etc that aren't coming out. It looks better than anything from a rattle can has a right to look.
Ok. You tell me which aluminum parts under the hood of my car are painted and which are natural aluminum. I'm guessing you'll get at least a few wrong.
Wow Multecs, which I assume are functioning normally.
The Alt. The dist. cover and the plenum don't quite match so one of those? Either way nice work on the engine. It looks great. I have been wanting it make my alt look nice and you just showed me how. Did you paint your tensioner pulley or polish that?
A trick I did, your engine looks so nice and those rusty manifolds just stand out, just like mine. I taped of the edge of the valve cover and parts of that metal heat shield below. I bought VHT flat black spray. I shot the paint into the cap. Bout a cheap 1/2 wide brush and brush painted what you can see on the manifold. It only took a short amount of time and came out great.I don't have a good pic but you can see it in this one.
As for making them look exactly as they did brand new, I don't have an answer. That being said, I've used countless products over the years which looked great, and to anyone else, you wouldn't know the difference. Best clean, yet stock look IMHO has been silver powdercoat with a satin clear. Constantly had people asking how I cleaned the "stock runners". ...also, I've found that all the cast paints give you an awesome finish. Been very impressed with Duplicolor. Again, not actual GM thirdgen factory looking, but they sure look they COULD have been factory.
...I also really like Eagle1 Never dull. Clean with soap and water, use the Never dull, wipe clean. I wouldn't use this on professionally polished metal, but on everything else, it's pretty nice. Like most things, technically it IS abrasive.
The key is to find a product which can clean stains without polishing the surface....
Agreed. ....but how many of "us" get our runners dirty? I think anyone willing to RE-finish a runner to look factory is probably going to take pretty good care of 'em. In all the years since I've painted and or powdered a set, I don't think I've ever had more than a little dust and dirt. Heck I don't even use water to clean mine. Just a microfiber towel.
I'll grade all guesses later when everyone who wants to take a stab at paint vs aluminum has had a chance to do so.
I'd say there are two ways to go, you can avoid the polished effect, or you can embrace it. Once aluminum takes a discoloration, it's virtually impossible to get it back to the typical even dull appearance. Cast aluminum is worse yet, because it's a bit porous and the rough texture holds onto grease, dirt, corrosion, etc.
Personally I'd start with the least invasive cleaning method possible. Something like a cleaner or degreaser that's safe for aluminum. Like Windex, Classic Dawn dish detergent and water, carb cleaner, etc. More aggressive staining can sometimes be removed with etching wheel cleaner for natural cast aluminum wheels. Just remember it's an acid, and you're cleaning the surface by chemically attacking the surface. Don't breathe it, don't get it on you, keep it off of paint, and be sure to flush it with lots of water. The finished result probably won't look "brand new, ORIGINAL" but it'll usually be clean. Acid usually will remove the glittery sparkles that a cast aluminum part has new. If you leave the acid too long, you can also get discoloration. For obvious reasons I don't like using the acid unless I'm lazy, desperate, or not overly concerned with how it turns out.
Another approach with mixed results is manually abrading the surface. A small stainless steel bristled detail brush can be used with decent results on rough cast aluminum. It's removing discolored aluminum, leaving being shiny aluminum, so don't get carried away. A wire wheel in a drill is carried away. For smoother surfaces, 0000 steel wool does the same thing with less tell-tale scratches. It also unfortunately requires follow-up cleaning to remove steel fibers, and the gray residue.
When all else fails, I turn to paint. Say you've got a piece of cast aluminum that has been covered in Indian Head Gasket Shellac for 30 years, or a puddle of oil from bolts that were installed without proper thread sealer, or a pool of anti-freeze from a leaky gasket or hose. If it's something with a lot of tight spaces that can't easily be reached with a brush, and the acid treatment isn't having any effect, paint while not entirely correct or an exact duplication of the original finish, is a quick and easy option.
Another process that works well on aluminum is submerging in regular green antifreeze on low heat for several hours or overnight. Anything on the surface will usually soften and lift easily. The catch is that anything larger than say a carburetor, isn't going to fit in a reasonably sized container of simmering antifreeze. It works wonders on old gummed up carb parts, pistons, etc. Just be sure the container never makes it back in the kitchen. Anything with delicate paint or plastic parts that should be preserved, probably shouldn't go in the antifreeze soak.
Blasting doesn't look bad, it just doesn't look right to me. Experimenting with different medias might come up with better results, but so far....
To date I haven't had a problem with this set of Multecs. They still Ohm out OK, and all 8 cylinders fire more or less correctly. I'm a bit suspicious of them because I replaced the injectors in everything else in the last couple years and the other cars showed marked improvement with fresh injectors. Maybe next spring, or after the project is painted and running...
I'm a bit torn on things like the valve covers, and exhaust manifolds. They look less than optimal, but repainting them gets away from the patina that they've earned in 120k miles of use. At the moment, they're real, if I do anything to them they'd lose something from my perspective. If the manifolds ever come off for some reason, a matte black ceramic coating might be in order.
Mid America sells the correct valve cover paint, it's called "Spruce". I used it on my 86 showcar and it was a dead match (and i'm super fussy). Calyx works mint for the exhaust manifolds, but it burns off every now and again.
Sounds nuts but White Wall cleaner works good on the dirty aluminum parts, you just need to be quick to avoid oxidation.
I prefer the "raw" unpainted look these days, but when I was younger I preferred everything painted. Drew, I agree, if it were mine id remove the valve covers and polish the paint and leave the patina.
As for the painted vs unpainted, my vote is the same as TTops, lower manifold and alternator.
Here is my current '91 1LE detailed, everything natural (except application of Calyx on exhaust manifolds)
This is my old 86 that I completely restored long ago. Everything seen was painted with correct factory type paint when possible... the polished aluminum bits were natural.
Not the best example, but here are two pistons, one was cooked overnight in an old crockpot filled with regular classic green antifreeze on low-medium heat, the other was not. This was after I got them back from my local machine shop. The shop was supposed to clean the ring grooves, but I sure couldn't tell they touched them. Being OE forged, turbo specific pistons and the block still had considerable crosshatching I wanted to reuse them. After the crockpot antifreeze treatment nearly all the carbon on the tops and in the ring grooves came right off. The manual labor involved a little light rubbing with an old toothbrush and a hot water rinse. The same treatment removes oil, paint, light discoloration, baked on grease and dirt, etc. Just don't overheat, don't leave the part cooking for too long, don't breathe the vapors, cover the simmering antifreeze, don't use the container for food after, and dispose of the dirty antifreeze properly. Sounds like a lot of warnings but it's mostly just common sense for toxic antifreeze.
For anyone still wondering, in the photo posted above of my Formula's engine, the intake base and alternator are painted. Everything else is bare aluminum. The Iroc is all bare aluminum. Try cleaning first, but don't discount paint. Some stains just aren't going to come out of some aluminum parts.
Last edited by Drew; 12-18-2016 at 01:48 PM.
Reason: Added ring groove photo
The paint color match is very very good. My old recommendation is to clean the heck out of your valve covers first because they for sure have had oil on them over the years and this paint will fish-eye if you are not careful. In general, I clean them with prep-sol, then lacquer thinner, then bead blast to remove the old paint, and clean with prep-sol again. Light coats with this paint and it will make them look factory fresh again
ev305tpi Thank you. that's exactly the info I was looking for.
Glad to help! Post up some pics when you start the detailing! Take your time with it and it will come out great. The pics of my restored car above took me an entire winter (that car had well over 100k miles on it and was a rusty mess when I started), but I won best motor compartment and best of show at a few shows with it back in the day after it was done, it's fun to see the results get recognized.
By the way, do you have any pics of your car? The color on yours is my favorite of all thirdgens!
are you saying what you pictured is a very low aggression product?
I am always looking for a better way to clean a casting that is grease / oil soaked and make it natural, without polishing it much or taking forever.
I have tried boiling in a light acid ( ever spend way too much time shopping for stock pots online? ) but not coolant.
I was able to clean the stains on my plenum, runners and alternator without polishing them with that product. I had tried a number of cleaning methods with little effect. I did NOT want to use anything which might leave a polished finish, that wasn't the look I wanted.
My next plan was to use an acid wheel cleaner but then I watched a youtube video on that Quick-Glo. It's used to clean chrome motorcycle exhaust pipes and rusted chrome bumpers.
They have two formulas. This is one is "original" formula.
For anyone still wondering, in the photo posted above of my Formula's engine, the intake base and alternator are painted. Everything else is bare aluminum.
By the way, do you have any pics of your car? The color on yours is my favorite of all thirdgens!
Only cell phone pics at the moment. It's a color that only gets noticed when in the sun. If it's cloudy, dark or in the shade it is boring and goes relatively unnoticed.
Only cell phone pics at the moment. It's a color that only gets noticed when in the sun. If it's cloudy, dark or in the shade it is boring and goes relatively unnoticed.
hardtop too... absolutely beautiful!!! Thanks for posting
The paint color match is very very good. My old recommendation is to clean the heck out of your valve covers first because they for sure have had oil on them over the years and this paint will fish-eye if you are not careful. In general, I clean them with prep-sol, then lacquer thinner, then bead blast to remove the old paint, and clean with prep-sol again. Light coats with this paint and it will make them look factory fresh again
Great,thanks for the info.
Sounds like a WINTER PROJECT
someone said Eastwood..their stuff is great..used it on my manifold..blasted manifold,then applied few coats...car wins most shows i attend..its all in the details.
I was able to clean the stains on my plenum, runners and alternator without polishing them with that product. I had tried a number of cleaning methods with little effect. I did NOT want to use anything which might leave a polished finish, that wasn't the look I wanted.
My next plan was to use an acid wheel cleaner but then I watched a youtube video on that Quick-Glo. It's used to clean chrome motorcycle exhaust pipes and rusted chrome bumpers.
They have two formulas. This is one is "original" formula.
I read through their site (who does that anymore?) and better understand your earlier post, and why it should work for me on cast alum., possibly with machine assistance on some nonTPI parts as well as some runners without machine.
The runners were bead blasted and I cleared them, which discolored. My hope is by stripping those, they can be closer to an original appearance. Thanks for researching, validating, and sharing.
I read through their site (who does that anymore?) and better understand your earlier post, and why it should work for me on cast alum., possibly with machine assistance on some nonTPI parts as well as some runners without machine.
The runners were bead blasted and I cleared them, which discolored. My hope is by stripping those, they can be closer to an original appearance. Thanks for researching, validating, and sharing.
Glad to help. Go slow at first and plan on losing your your fingerprints if you go bare handed.
Thanks all for the input. I've got the project about 90% finished. Just working on all of the tiny details for now. Here are some photos. I used the Spruce "nickel" paint on the valve covers. It's not perfect, but close. Lower manifold, alternator and brackets were done in cast aluminum. Yeah I know the valve covers were backwards, I swapped them out Still some work to do but light years better than it was.
Has nobody mentioned using an Ultra Sonic parts cleaner? A guy by me has one and as long as the part has no rust, it will look brand new coming out. The crock pot method I have never heard of but now I really want to try it. Only problem is I have no dirty parts...
What about the paint in the engine bay (for example on the strut towers)? It's not cleared and finished as nicely as the exterior. What sort of polishing compounds or touch-up methods have people used to get the paint clean and original looking?
What about the paint in the engine bay (for example on the strut towers)
Windex.
Odorless Mineral Spirits for really bad spots, but be careful it'll remove OE basecoat if scrubbed too hard.
My Formula had a ton of overspray from a quicky dealer touch up, and dingy areas from parking under a tree one summer. I used one of the Meguiar's Mirror Glaze compounds. Not sure which variety exactly, but somewhere in the middle of the scale printed on the label. Applied and buffed off with a soft cloth.
Meguiars M205 would be a much better fine cut polish. It doesn't sling nearly as bad and breaks down. Lots of the old Meguiars polishes are just variations of liquid sand. I've tried all of their older compounds and abandoned the bottles after one use to switch back to their M105 and M205.
Glad to help. Go slow at first and plan on losing your your fingerprints if you go bare handed.
I am just poking around with some previously loved, polished, abraded, and dented runners now. It is funny how it doesn't create a polished sheen with the little effort so far.
Also, stripped my cleared set. I have faith those can look more OEM, but for now, they definitely look bead blasted.
Thanks all for the input. I've got the project about 90% finished. Just working on all of the tiny details for now. Here are some photos. I used the Spruce "nickel" paint on the valve covers. It's not perfect, but close. Lower manifold, alternator and brackets were done in cast aluminum. Yeah I know the valve covers were backwards, I swapped them out Still some work to do but light years better than it was.
To clean the runners, plenum and lower intake manifold, I got a big container and put all of my parts into it, soaked it in that cleaner in a purple bottle, I think it's called super clean (very strong smelling), kept spraying it onto the parts and scrubbing them with a nylon brush. It worked extremely well and didn't change the finish of any of the parts.
Super Clean used to be known as Castrol Super Clean. Under the Castrol branding, it used to carry a large paragraph of warnings. Hidden in that paragraph was a note that it will attack aluminum. I noticed the warning after the aluminum pop can I had cut in half and was using as a container melted and spilled dirty Super Clean all over my workbench.
I browsed the current Super Clean jug in the last week or two, and don't see that same warning, but I wouldn't be surprised if the current version is still caustic to aluminum. I know it dissolves lesser forms of paint, and has a mild effect on undercoating. It has it's uses, but I'd keep it away from aluminum... Just in case...
Seems Simple Green carries an aluminum warning too...
Super Clean used to be known as Castrol Super Clean. Under the Castrol branding, it used to carry a large paragraph of warnings. Hidden in that paragraph was a note that it will attack aluminum. I noticed the warning after the aluminum pop can I had cut in half and was using as a container melted and spilled dirty Super Clean all over my workbench.
I browsed the current Super Clean jug in the last week or two, and don't see that same warning, but I wouldn't be surprised if the current version is still caustic to aluminum. I know it dissolves lesser forms of paint, and has a mild effect on undercoating. It has it's uses, but I'd keep it away from aluminum... Just in case...
Seems Simple Green carries an aluminum warning too...
Yeah, Simple Green is tough on Al. When I use it to clean engine compartments, I stay cognizant of that, work quickly, and rinse with water THOROUGHLY afterwards. Otherwise, you risk etching runners and plenums.
I had tried the factory or as cast aluminum colors in powder coat and paint and they always fade to the dull grey. Interested to hear others long term results.
12-14-2016, 07:58 AM
Ok. You tell me which aluminum parts under the hood of my car are painted and which are natural aluminum. I'm guessing you'll get at least a few wrong. 
The shop was supposed to clean the ring grooves, but I sure couldn't tell they touched them. Being OE forged, turbo specific pistons and the block still had considerable crosshatching I wanted to reuse them. After the crockpot antifreeze treatment nearly all the carbon on the tops and in the ring grooves came right off. The manual labor involved a little light rubbing with an old toothbrush and a hot water rinse. The same treatment removes oil, paint, light discoloration, baked on grease and dirt, etc. Just don't overheat, don't leave the part cooking for too long, don't breathe the vapors, cover the simmering antifreeze, don't use the container for food after, and dispose of the dirty antifreeze properly. Sounds like a lot of warnings but it's mostly just common sense for toxic antifreeze. 
