Jump to content
HybridZ

To Powder Coat The Motor Or Not Is The Question?


S30TRBO

Recommended Posts

I dropped off my valve cover and misc engine pieces to my powder coater. He asked me what are you doing to the block? I said I don't know just paint it black "like factory turbos came" and clear it. He said why don't we powder coat the block, pan and front cover? I said hmmm....

 

I talked with my machinist and asked his opinion and he said let me ask around and get back with me in a couple days. He thought it would trap heat and I said my powder coater said it dissipates heat.

 

I just got off the phone with him and he asked on the Chevelle forum and they had 2 or 3 motors done and didn't have any problems i.e. bores warping since the parts have to be baked up to 400-450 degrees.

 

Has anyone had this done?

 

This is the color of my suspension and the valve cover is getting coated the same way except for the lettering and trim, regardless if I get the block done or not.

 

f61ad20e.jpg

 

 

My machinist is going to ask around some more and said call me back on Friday. He also mentioned if we did it how would the logistics work. I asked is it better to get it coated first then bring it back for boring,honing, decking or vise versa. Also moving it around the machine shop what are the chances if something happens even though the finish is not glossy. I told him I'm getting a textured finish so it won't scratch very easy.

 

My powder coater quoted me $600-$800 to do the block, pan, front cover ,valve cover and some brackets. My machinist said that he has had lots of painted blocks and knows of a guy that he did his motor for and he is a painter and said he might be able to paint and clear mine for $100-$200, but didn't know for sure. He said this guys block (the painter) was painted 10 years ago and still looks great.

 

 

I wonder if it's a waste of money. I'm debating because I can use the money else ware towards....I don't know a set of these maybe:

 

 

mumei.1.jpg

16x7/16x8 RS Watanabe

Link to comment
Share on other sites

I powdercoat, not a pro, you understand, but my friend and i have powdercoated many engine parts for our cars and our friends cars. It looks great, and if i were you i'd do the valve cover, 'cause it would look really nice, but to do the block would just be stupid. $600-800 is a lot of money, and you wouldn't REALLY get that much out of pcing the block. to each his own, but as someone who powdercoats, i just wouldn't do it. just get it painted.

 

however, if you do get it powdercoated, or painted, have all the work done first. if you spend $800 having it powdercoated and some new guy at your shop touches your car and scratches it, you won't be a happy camper.

Link to comment
Share on other sites

In tempering steel, 400-500 degress is the top end for relieving stress in steel and 1200 degrees will get it as soft as possible. Your block is high grade cast iron (not steel). Ceramic coating is advertised to keep the heat in. I have always heard that flat black will disipate heat faster than any color. By powder coating the block you maybe relieving stresses in the cast iron that are beneficial or are part of the bore. The powder coat may retain heat in the block more than normal. Contact powder coat manufacturers and ask them the effect powder coating has on cast iron blocks and if they recomend it for that purpose.

Link to comment
Share on other sites

I powder coated my turbo block and it does not run hot at all but I also have a MSA alum radiator that works very well. I can't tell you if it makes it run hotter or not. I paid $150 to have the block done but it was only the 2nd block this guy had done even though he has been in buisness for many years. I also had the machine work done first then they just use a plastic like tape for masking and as long as they do a good job masking you should not have a problem. I did a candy apple red on my block and it is kinda translucent so you get some small color changes depending on the roughness of the surface. If i was to so it again I might want to smooth the block first, but then I'm kinda sick like that. Just use a solid color and it will look great forever.

Link to comment
Share on other sites

Guest nikko74z

Buddy, this powder coating guy is close with $600 if that includes blasting and cleaning as well. I powder coat v-8 blocks for $250! If you were in Houston, I would have done it for about 500 to 550. The coating will basically seal up all the pores in the metal and the color will not come off when oil or gas touch it. I am no rocket scientist, but the heat is generated inside the block. How will painting the engine black on the outside help it disappate heat quicker? Black on an exterior surface will absorb heat because unlike white, it does not reflect it away. Does this mean painting my engine white will keep it cooler? No. The power coating will bond to the metal thus becoming a medium for which the heat to travel through. Now, powder cures at 350 to 425 degrees depending on the type of powder. A block wont see more than 235 in most applications. You can even clear coat using powder as well and it wont yellow on you either.

Link to comment
Share on other sites

The color black "transfers" heat more efficiently than other colors. So if the external temperature is higher then an object painted black, the object will absorb heat more efficiently than if painted white. On the other hand if the internal temperature is hotter, then black will radiate more efficient than white. Since the block on a running car has a higher temperature than the ambient air, black will radiate the heat from the block out of the block more efficiently.

 

Realistically, if you compare apples to apples, or a black paint to a white paint, IMHO I don't think the layer of black paint vs. white paint is going to make a significant difference. The same should apply to powder coating; if you can safely powder coat an engine block, the color won't make a dramatic difference.

Link to comment
Share on other sites

My point was to consult a powder coat manufacturer if in doubt about powder coating an engine block.. You are right a black car left in direct sunlight will get hotter than a white car similarly placed but we are not talking about sunlight heat absorbtion on surfaces but heat generated inside an internal combustion engine. Being from the North west, I have been around a few wood stoves that put out more heat to the room than up the chimney if painted black. Cast iron is a remarkable substance when it comes to high temperature and transfer of heat but oil seems to go crappo when exposed to high heat and you cannot seem to change the oil enough for a turbo charged car

Link to comment
Share on other sites

maybe this point is null, but it is the reason I have shied away from powder coating my block. The powder coat itself is not as good a conductor of heat as the cast iron is. Therefore it might trap heat in the block that would normally be drawn out. I think this was also the point "Here comes trouble" was making at.

 

The color affect is null for sure. It's the actual substance that the powder coat that I am worried about. Powder coat as I know it is a ceramic in nature. Ceramics don't conduct! They insulate. So are we trying to insulate the block or draw heat out of the block.

 

I did think about several other options as well, but after rethinking it they won't work with the setup I am trying to build. Like some kind of crankcase blow through system that flushes fresh air through the crankcase and evacuating heat along with a 3 core radiator. But I'd much rather run a vacuum in the crank and the larger radiator!

 

But then again I could be completely wrong.

Link to comment
Share on other sites

Cause I would really like to powder coat my engine to.

 

I think the main difference is that heat is conducted through the iron block but has to radiate through the ceramic coating. Trying to radiate the heat through the coating is very hard! This is a potential problem. Paint is pretty conductive itself so it isn't a problem.

 

Just my theory...

Link to comment
Share on other sites

Guest JAMIE T

Powdercoating is not ceramic, it is plastic. Usually polyester or epoxy or a hybrid of the two. My machinist recommended coating the block BEFORE machining. In the case of any movement in the block, the machine work would not be disrupted. I would not be concerned about PC holding in heat unless the mil thickness becomes 10 or more. At that point even liquid paint would hold be an insulator as well. I've powder coated Magnesium Porsche engine components and Porsche over head cam heads.

Link to comment
Share on other sites

If I were you, I would get a $7 can of engine paint and call it a day. I wouldn't want the stress of chipping the powdercoat on installation. With paint, it's easier to touch up in the long run.

 

 

I think your right. However, I do plan on getting the valve cover, lower alternator bracket and diff coated to match my suspension.

 

I just **** $2000 at MSA so I'm not feeling the $600-$800 powdercoat job. Plus I would hate for something to happen to the block then all that money will be wasted.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...