I want to paint my LS1 intake, valve covers, and the Throttle body.

I notice the plastic intak has several 3/8" diamater molding marks in several places on the top. I thought I had seen an aritcle/post on painting the intake here, but can't find it now.

Any recommendations on how to do this? Method/what to use for smoothing? Type of paint and primer?

Same questions for throttle body. On the valve covers, I presume I can use some type primer for aluminum.

All of my past experience is on iron engines, so I want to be sure I get it right.

 

well i just fined up with my ls6 intake and valve covers. now you want the intake as smooth as possible. so that means sanding. i used some 700 grit sandpaper. now this is going to take a long time. but trust me worth every minute. you want to start by sanding the top of the runners and work your way down. its very hard to sand in the tight areas i used a dremel to get in there but be careful! so after you have sanded it down and gotten ride of the ridgest from the casting you are ready to primar. i went to your local auto store and got some sandable primer. and i gave the intake alot of coats. once you think yo have enough coats to start sanding you want to get a real fine sand paper. i used some 1000 or finer paper. wet sand the intake at this point. you will repeat the primer and sanding stage a couple of times til you get it as smooth as possible. let it dry and pic your color. i went with a metalic forest green. to match the color of my car. oh just a little bit of info if your intake is the same color as your car it really sets off the engine bay! so get your paint. i used normal the spray can paint for your car exterior and it worked fine. the intake for the most part is dry so you wont have to worry about it getting super hot and messing up the paint.

so spray light coats until you intake is painted. now you want to sand it again. but use really fine sandpaper for this task. and wet sand it again. and then you paint it again. and once you are satisfied with your work and it is smooth. you are free to clear it. i used engine enamel clear coat for this. worked great. and hopefully you intake will turn out exceptionally well.

now for the valve covers i personally sanded my vavle covers before i even primared them. so i could have them as smooth as possible. even though they would be covered by coils attention to detail! sand them then primar them. wet sand them again and if your happy paint them with engine enamal that you can get at your local auto store. and once thats dry i just cleared them with the same engine enamel clear coat that i used for my intake and put them back on the motor after they dryed.

here are a few pics of my finished product. i wish i would of taken more pics of the process but oh well.

this was after washing i was completely done. its dark forest green.


and here is the motor assembled. oh and i painted the fuel rail as well.

 

Looks very nice. So, I guess it's really like doing body work. Use sandpaper, get it prepped, primer, sand, paint, etc. I've painted several cars, so I'm not new to painting. Just wanted to be sure about thoughts on the intake.

Next, to be sure about the throttle body. I presume it's teh same. I think there is a special primer or somethign that should be used on aluminum, such as the throttle body, and the valve covers.

My 56 is two tone. I plan to use the same colors on the engine. That would be a very off white, almost cream on the intake and valve covers, and Candy Burgandy on the coil covers. I plan to have BelAir Gold Leafed on them.

 

I had my trusted body man do my intake. He sanded all the casting marks off then used a high build primer designed for plastics, like the kind used with bumpers these days. The high build primer fills in a lot of the rough areas and saves you some work. Then he sprayed it with the same paint used on the rest of my car, which is a PPG single stage concept paint.

 

You will want to use a self etching primer on the aluminum, than your sandable primer, sealer and paint. Also, I would use a plastic adhesion promoter on the plastic intake, before you prime it. That will insure you wont have a peeling problem in the future.

 

use some bulldog adhesion promoter, its hard to beat for the money.

 

+1 bulldog adhesive. I used "poly" primer, then high build, sanded it well, then base/clear. I'd make sure it isnt chunky or too thick before you lay it on, it's a b__tch to sand it down by the injectors.
olly

 

Thanks guys. This is good info.

One question on the manifold: There is a connector on the back. It looks like possible a good twist and it would disconnect. True? I'm thinking that should come off before painting.

One question on the valve covers: The oil filler neck seems like pretty solid plastic, and in there pretty good. Am I going to break it getting it out, or will I be successful if I just gingerly pry it, moving around it, until I get it out?

 

I think you will find that there is a small catch or latch similar to an electrical connector holding it in. Take a look at the filler neck from inside the valve cover. I'm quite sure that the catch can be released with a small screw driver, releasing the filler neck so it can be un-screwed from the cover.
Ken

 

I asked the same question about the connector in the back of the manifold but didn't get a clear answer on taking it out. Since I'm not going to force it and risk breaking it, I'm leaving it in when I paint the intake body color - bright silver. I'm using a Bulldog adhesion promotor, high build primer, then Duplicolor primer and Duplicolor silver.

I killed my oil filler neck taking it out of the valve covers since I couldn't find the release but now have a billet aluminum machined unit in them and the covers have been powder coated.

 

I just masked off my vacuum port in the back of the intake.

 

Where did you get that valve cover breather? The stock oil fill neck won't clear my hood and that would probably be a perfect fit.

 

I'll have to ask. The friend selling me the LS6 just up and gave it to me since he couldn't use it in the LSx RX7 with tall valve covers.

I'm working away from home until 8/11, so if you'll remind me around 8/12 I'll measure it's height for you to see if you have the room. It looks taller than a stock filler neck to me, but I could be wrong.