Painting bottom of intake manifold with ceramic paint

[babybolt]

Using heat resistant paint (header paint) on the bottom inside of an aluminum intake.

Just wondering if this is a good idea or will the ceramic particles in the paint get into the oil as the paint ages or wears?

[plovett]

Well I don't know, but my opinion is don't do it.  The risk to reward ratio is too high.  Paint flaking off could destroy your engine.  While the gain from a slightly cooler intake will be minimal or not even measurable.

JMO,

paulie

[Nightmist66]

Can't say how regular paint would hold up, but we've been using Glyptal #1201 for decades without issue. FWIW

[hwoods]

wonder where Jay is on those carbon fiber intakes?

[blykins]

I wouldn't coat anything. 

That stuff *can* come off.  I've seen the Glyptal come off and once it starts, it just starts flaking. 

IMO, paint/coating doesn't belong anywhere in an engine, except for coated bearings and coated piston crowns/skirts.

[Falcon67]

Why - block the heat crossovers if they exist with .010 stainless shim stock and run a good spacer like a Moroso 4 hole (if clearance allows) to isolate the carb.  You'll get hella lot more heat conduction from the heads than anything going on under the intake. 

[falcongeorge]

I have used the TBC-1, I WOULD NOT use header paint, I really doubt it will stick, and if you have that crap floating around in your oil, you are going to be in DEEP shit.
http://www.hpcoatings.com.au/coatings-2/#Engine-Coatings

Where I had a problem was applying it to the bottom of a used intake, it appears that oil gets baked into the bottom of the heat riser passage, it flaked off the bottom of the central part of the heat riser passage and stuck everywhere else. I also used it on a new intake, and it worked well. I cleaned both intakes VERY thoroughly before application, but I think the oil on the bottom of the heat riser is baked right into to pores of the metal, and only comes out under heat.
IMO, where it really shines is on the face of intake valves. I totally disagree with most of the membership here, anything and everything you can do to keep heat out of the intake tract will raise the detonation threshold. IMO, that stuff the magazines love so much thats smeared all over piston skirts to try to convince you that you are buying "high-tech" parts is a total eyewash, and serves no useful purpose whatsoever, but that's just my opinion.

[Joe-JDC]

I just paid to have a set of forged piston skirts and domes cleaned and re-coated with a supposedly thicker/larger media to decrease the clearances.  After paying for shipping two ways, the coating, and getting them back looking pristine and ready for rings, the micrometer showed that they were exactly the same size as before shipping off.  I called, they said send them back, and a repeat.  NO DIFFERENCE in piston skirt dimensions!  After wasting shipping costs twice, two applications of coating media, they ended up exactly the same size as shipped from Diamond.  I am not a believer at this point of time since the company is supposedly into Nascar, Pro-Stock, Turbos, Blowers, and were supposed to be the ultimate in piston coatings.  They said they could increase the skirts by .0015" per side or .003" overall, and they came back exactly the same dimensions, as tested by two shops with the pistons at various temperatures to match the micrometers.  JME, Joe-JDC

[Galaxie505]

I bought a fe that was block and manifold painted, it was a nightmare.  I wouldn't do it, came off in sheets and found it's way into oil pump

[wayne]

I have used rust-oelum rusty metal primer in the lifter valley and top of the heads for years with no trouble.     

[Barry_R]

No paint inside of any engine we build.  Unless it was already on there from a prior build and seems perfectly adhered.  And I hate that being there too