Looking for suggestions for bearing and rings for a blown 355 I'm building

have heard of some teflon coated bearings but have been unable to find any, maybe they are just a myth? The best I can find are the tri metal pieces that clevite make

Rings I was thinking of the plasma moly rings probably file fit, curious as to what I would set the end gap at though. Also wondering they are necessary or if the standard tension rings would suffice

 

The bearings probably don't matter because the bearing and crank never contact each other anyway (oil film).

Plasma Moly standard tension rings are good. Although, you may get the non-file fit because it gives you a big head start on file fitting. I set my gaps at .018" - .020" 2nd ring and .024 - .026" top ring.

Mike

 

you could also look into federal mogul hellfire rings suppose to be for supercharging and turbo use

 

I would personally go with Clevite 77 bearings, and SpeedPro Hellfire rings

 

>I agree ... you pay a little now , but you won't have to think twice about them later .
This is for the Hellfire rings :
http://www.federal-mogul.com/cda/con...5_6806,00.html

 

How much power are you looking to make - no point in going with the hellfire rings if you aren't stressing normal plasma moly rings - the hellfires will just wear the cylinder wall faster.

Chris

 

I would recommend plasma-moly rings(speed pro). Im using them in my current motor with no problems. As for bearings tri-metal is the best, I usually get speed pro or clevitte 77 which ever is available .

 

If you have large radii on the crank, make sure you get the "H" series bearings.

Mike

 

Whatever bearings you decide on believe this- get the front main bearing clearance DEAD PERFECT in every way. That's the one that takes a real beating from the added force of the blower drive belt's tension. It tries to pull the crank snout up into the block and the upper half of that front main bearing gets a LOT of force (and therefore wear) put on it. Be super-**** about perfect oil clearance on that one.

An align bore/hone operation on the mains is probably a good idea if anything is even slightly outta line down there, too.

Remember if you're adding 100HP at the flywheel that's AFTER the blower sucks up 25-50HP more off the front of the crank to drive itself.

 

I've never used the hellfire rings, but do they contribute to faster cylinder wear? Their webpage says they don't, but that is just propaganda. You have any real world experience with these?

I currently use Speed Pro plasma moly rings, and no problems up to 18 psi.

Bill

 

how does the selction of bearings and rings for a blown motor differ from the selction for a N/A motor, or do they?

 

For the kind of motors 99.99+% of us are building, I'd say that there isn't any difference. The one exception that comes to mind is that I would stay away from aluminum bearings for a blower or nitrous application. Aluminum bearings are becoming widely used by the OEM's. But the one main disadvantage they have is that they have less load carrying capability than copper/lead bearings. Copper/lead can carry ~12,000psi versus 7,000-8,000psi for aluminum.

Rich Krause

 

Nope, haven't used them myself - that is just from talking to people who have experience with them.

I think the claims of reduced wear are vs. tool steel applications, as they come in at the low end of what used to be the "requires tool steel" power level. They are definitely better vs. those rings, but just based on their characteristics I would surmise they will show greater wear than a normal plasma moly.