thoughts on crank polishing?

[ericjon262]

I'm interested in thoughts on crankshaft polishing I may have found a crank for project full retard, and was wondering if polishing a crank would be worth anything in a dry sump application?

[The Dark Side of Will]

Micropolishing the journals is worth it, especially for turning it at ludicrous speed.

I haven't heard much either way about polishing the rest of the crank... I assume you're talking about a lot of hand work to smooth out the surface finish.

What are you doing with a non-billet crank under NASCAR heads? Polishing the rest of it is only an issue if it's a forging or casting and has a rough surface finish.
There are also oil shedding coatings on the market which can help keep oil from sticking to the counterweights thereby reducing windage losses.

A simple dry sump system won't necessarily reduce windage losses. You need to engineer the system so that it can pull crankcase pressure below ambient. That mostly has to do with the front and rear main seals, as they're not typically made to hold in vacuum (or hold out pressure, depending on your point of view).

[ericjon262]

who said it's not a billet crank? I do think a forged crank could be stronger than a billet crank though. a billet crank is cheaper to manufacture small scale than a forged crank. as far as engineering a dry sump system, all R07's are dry sump. the crank I have now is a 33 pound hunk of billet steel. the surfaces are smooth, but I would not call them polished either. got any links to the oil shedding coatings?

[The Dark Side of Will]

I was joking with you, hence the

Techline: http://www.techlinecoatings.com/article ... rticle.htm
and
PolyDyn: http://www.polydyn.com/performance_coatings.htm
Have oil shedding coatings.

Swain probably does as well, but it's not easy to find on their website.

If you really want to get NASCAR level results from your R07 build, you *NEED* to be a member at www.speedtalk.com and hang around the Advanced Tech forum. It's full of guys who've been there and done that at the professional level.
Example:
http://www.speedtalk.com/forum/viewtopic.php?f=1&t=8026

I know R07's are designed to be dry sumped, but I had not heard that you had obtained a block yet, which leaves that part of the equation somewhat open ended...

[ericjon262]

I was joking with you, hence the

Techline: http://www.techlinecoatings.com/article ... rticle.htm
and
PolyDyn: http://www.polydyn.com/performance_coatings.htm
Have oil shedding coatings.

Swain probably does as well, but it's not easy to find on their website.

If you really want to get NASCAR level results from your R07 build, you *NEED* to be a member at http://www.speedtalk.com and hang around the Advanced Tech forum. It's full of guys who've been there and done that at the professional level.
Example:
http://www.speedtalk.com/forum/viewtopic.php?f=1&t=8026

I know R07's are designed to be dry sumped, but I had not heard that you had obtained a block yet, which leaves that part of the equation somewhat open ended...

Thanks for the links

I've been a member on speetalk for about 5 years, never posted, I guess I joined and forgot about them... pretty cool Ideas over there, I'm gonna do quite a bit of reading and learning from them. I think my crank has some kind of coating on it already, but it needs to be removed and reapplied. I haven't seen much on the R07 dry sump system, but I have seen a picture of the front crank seal, and it looks very robust, much more than I expected.

[ericjon262]

lol, so my speedtalk account was 5 years old, and so was the email address... no big deal I'll just update that... and now I'm locked out... LOL.