Painting or Powder Coating Exhaust Manifolds
 

While the heads on my '71 Formula are being redone I'd like to do something to improve the torched appearance of the exhaust manifolds. What I don't want is something that just bakes off after a few weeks / months.

1.) Does powder coating hold up better? Should they be sandblasted first?

2.) If I go with painting them, what is a good brand of high-temp primer, and is there a prep product you apply before or after primer for better adhesion of the actual header paint?

3.) Lastly -- what's a brand and shade of header paint you'd recommend?

Thanks to you all as usual for your expertise.

There are a few high temp powder coats out there. A friend had his done, but the shop had to buy the powder in bulk, wasn't cheap.
The best. However is Ceramic coating. This does them inside and out. Lasts forever.
On a side note. To retain Any coating in middle of the head exhaust ports And lower head Temps, drill the block ( use a head gasket, vacuum) and drill the heads too ( again, use a head gasket for size and location). This really keeps the hottest part about 30 degrees cooler. Search 421 cooling mod.

Ceramic coat is best as mentioned, but if you dont want/need to go that route, ive had very good luck using the POR brand high heat exhaust manifold paint, just needs basic clean & prep, can wire wheel them or do a quick blasting. Instructions are pretty simple and the color looks exactly like new cast iron. Has lasted on my 81 turbo manifolds & cast iron wastegate for 10+ years. Eastwood makes a similar product.

Another option is VHT paint in a spray can, I have never used it but have seen it on headers on a few cars, seems to last pretty good.

I have used the Por with good result.

Did a set recently for my 421 using the POR-15 manifold gray. Previously used it on another set of RA manifolds and after 5 years and 30k miles of daily driving it still looked nice.

Pretty much your best option for value and durability. This stuff has a long shelf life, I’ve used it 20 years after first opening the can and it was still fine after thinning it with a little mineral spirits.

Same here, my can is about half full after doing the manifolds and still liquidy.

I also used the POR-20 on a set of headers, it stayed nice for about 5-7 years, then started getting rust stains and light pitting at about 8-10 years, now its ugly with heavy rust stains and pitting on the areas right off the head but surprisingly its not flaking off, still intact just heavy discoloration. I plan to sand them down someday and try the VHT paint.

I also mixed the manifold & header paints to get a more silvery color for the steel up/down turbo pipes, that mix has lasted 10+ years with no signs of rust stains.

whoa those look good...

too bad they don't make pontiacs out of Por15

I have used the Eastwood High Temp manifold paint and it holds up for a long time. I would be interested in ceramic coating. Any recommendations for a company that does it? I tried contacting that one that advertises in Hemmings Muscle Machines, but they never got back to me. I guess they don’t need the money!

For ceramic coating I used a local place that does powder coating too, very reasonable cost of about $250 for a pair of big 2" hooker super comp headers, probably more expensive now with the current inflation crap but better than shipping the part to & from, have read bad reviews for some of the bigger places like "jet hot."

Heres a pic of the headers dome locally in a shiny silver and no signs of failure after ~8 years and some dyno time with lots of drag racing & street miles.

Those headers look great. Thanks for the feedback. I will check out some of my local powder coaters.

Mine are at a local Gun shop getting " ceracote " . Will post pic when I get them back.

Por manifold paint.

Did you spray this on or brush on? Thanks.

I saw advertisements for “ceracote”. Is it similar to ceramic coating? Thanks.

How did you apply the POR-15?

You brush it on. Any brush marks will disappear.

Use 2 coats 24 hours apart.

Ok, did the brush marks disappear without heating in an oven? I see they also sell it in aerosol spray cans. I have a compressor and spray gun, but like to avoid the chemicals.

Cerakote is the ticket:

https://www.cerakote.com/cerakote-vs...koteVsHighTemp

Just put them on and run them, no need to bake the manifolds in an oven. The brush marks pretty much disappear after they dry.

They look fine with just brushing on the paint but do whatever method you prefer.

No better oven than starting the car!