Quality of 1.8 Block casting/ Crank Coatings
 

Hey guys,

i'm helping a friend build a motor over the winter season (1.8 out of a 97'), and I have some questions about crank case coatings and the quality of the cast iron 1.8 blocks.

I've seen DSM and hot-rod guys use a product called Gylptal on the inside of their crankcase:

Glyptal 1201 Paint - The Eastwood Company

Its an oleophobic coating and people have used it to ensure oil gets back into the pan quickly and doesn't aerate to prevent losses in oil pressure. Others have said it prevents oil from lingering on the porous and roughly cast surface of the crank, and DSM guys have told me it prevents carbon buildup and other nasty engine deposits from the PCV or Blow-by. All of them said its to compensate for the rough casting, especially in the oil return gallerys.

Anyone have any experience with it in a Miata? How rough is the cast iron block on the 94-97 1.8's? Is it worth it for a car that will (eventually) be daily driven? The motor will have a turbo, so better oil flow back into the pickup could be beneficial. Would the coating be a good idea for a car that might have many more accessories that have oil feeds, such as a cooler and a VVT system?

Let me know what you think.

Might be able to shine a little light on this, back when people were still racing small block chevy's they were fighting oil starvation issues. They found that oil liked to pool in the heads especially in a high G load scenario. All kinds of things were tried to help alleviate this and that's one of the first times I saw the block paint (that's what it is) being talked about. The real problem was that the oil drain's were way too small and poorly located. Dry sump was the easy answer, the slightly more involved and cheaper solution was external drains to the sump from the heads.

Let me ask you this, do BP motors suffer from oil starvation? Ever hear anyone here talk about aeration problems? Ever see anyone talk about having to smooth up oil drain passages?

The answer to all of these questions is no......I wouldn't waste your time, but that's like my opinion man.

I think its way more hassle than its worth, and only people like marcello do shit like this.

Bronson, thanks man, that was 100% what I was hoping to hear. Both of us kinda stumbled upon the Glyptal and I figured people here would know something about it.

Sean, I think you're right. I don't think we are going to coat it.

Thanks guys.

Polish off the insides off the casting. This will aid the oil to flow down into the pan (not really an issue) and reduce the risk of any sand vibrating loose into the oil and causing damage. 98% of builds probably don't need this but at the top level it should be done.