Rebuilding the engine in the roadrunner. In the past I've always used rattle cans to paint engines (duplicolor, Mopar Performance, etc) but I've never been too impressed with how the paint looks like after a year or two, seems like it lifts with coolant leaks or stains easily with oil. I was considered painting this engine with enamel in the HPLV gun in the hopes that the paint would be more durable and look better longer. Am I wasting time and money or would I be much happier going this route?

A few professional painters I know say spray gun - has more solids in it than a rattle can does.

For decades I've used pretty much every brand of rattle can paint then a few years ago a friend suggested I try some good single stage paint out of my gun. Ever since I've been using Nason Full Thame over self etching primer and been really happy. Sure holds up so much better and last for years. I drive my cars year around. Does cost a lot more. Around 80.00 per pint plus hardener and reducer and that is enough to do 2 motors. Big down size is that they are probably more shinny that the original paint jobs,

Some more motors.

Yes, those are shinier than the factories did them, but better looking.
An argument can be made that nowadays, people expect them shiny, and I get that.
I've usually painted engines with cans, and over a thoroughly clean & primed engine, they've held up fine for 30+ years.
They all look recently done, but I keep them clean.
I've also used the Bill Hirsch stuff, and it was excellent.
So, whatever you like and are equipped to do, I guess.
It's one of those debates that will go on forever.

Those do look nice!!!

I wonder if they could add some "flatner" to the paint to make it look less shiny??

I also paint all the bolt on parts with Nason gloss black. The way I see it in 10 years and 60,000 miles they will be just right.

I don't know.

I would think you could add a flattening agent, or a satin/matte clear.
But I don't know if either could have a problem with heat or staining.
I'd be curious what the top restorers - Mike Mancini for example - are doing.

I would think for a correct restoration you'd want to use an enamel not a urethan like I do. I build really nice drivers not correct cars so the shinny motors work for me and my customer.

My cars are drivers as well and I don't mind the shiny paint on the engine. I'll look into using enamel and see what folks suggest.

Thanks again for sharing your experience/pictures.

Throwing some gas on the fire here....

Graveyard Cars seems to spray their engines with a paint gun.
I have always used spray cans but have had mixed results. I've had paint lift and peel on some engines and stick like glue on others. The Mopar Performance paint used to be good but at some point, they must have changed something because the cans wouldn't spray, the color would come out uneven and I'd end up having to use a different brand.
I am going to try a gun next time I rebuild an engine.

Absolutely yes you can.

I paint engines with Urethane paint (paint gun obviously) and add flattening agent to the mix if I want it more dull/satiny like the factory look.

How much flattening agent you add affects how shiny or dull the paint ends up when it's dry.

On something that isn't stock/restored I prefer a shiny paint on the engine.

Urethane holds up far better than rattle can.

Self etching or epoxy primer than paint with urethane is what I do.

I’ve been larryLOVEit the Duplicolor paint fer years ....

Well at least my grandpa has !!

They used a gun at the factory.

i myself prefer using a spray gun.
regular enamel paints can successfully be sprayed without using catalyst and only using reducer. it won't be as durable as with catalyst but more durable than a bomb. without catalyst will leave a duller finish. i THINK the factory sprayed this way.

if you don't have access to full air pressure to use a spray gun.
you should look into PREVAIL sprayer. they are basically a make your own spray bomb setup. i have used the hundreds of times in small areas. actually they seem to spray much better than a spray bome.
most quality hardware stores sell them. i know the home depot and ace hardware store near me sell them.

prevail sprayer

I used to use Plastikote paint back in the 70’s and 80’s when they were out of Medina Ohio.
Was the best paint available, better than Direct Connection.

The DC orange ran when hit with fuel but Plastikote didn’t budge.
One coat usually covered, two coats was perfect.

Just found out they were bought by Duplicolor.

Any chance of getting the paint codes you use or is it one of those "if you look it's obvious" kind of thing.

'Single stage urethane with a hardener is the gold standard paint for this type of application. Engine must be primed for this to work well. Acrylic enamel or a ceramic engine paint both with hardener are also good choices. Regular old spray bomb enamel type paint is the bottom of the barrel. It is like potted meat v/s a steak. If you are hungry enough you will eat either, but there is no comparison to the good stuff.

As far as a correct restoration goes, I have no idea as I don't care about that in the least.

PS I have also read about people using equipment paint with success but have not done so myself. I would only use one designed to mix with a catalyst or hardener of some sort if I chose to try it.