So what are the rings and bearings of choice in a stroker blower/nitrous application. Say running in the 15psi range? Must have been too aggressive on my tune so now i'm in there unfortunatly, but while i'm there, i wouldn't mind putting in better parts if there is better then what i already have out there. Was running Clevite H series bearings with Speed Pro Plasma-moly rings. Currently up in there air as far as pistons go. Leaning more towards a set of JE blower pistons, but have considered Dimonds to replace my SRP's. Any input on that out there? Thanks.

Ken R.

 

I have another set of those SRPs that I'll give you a smokin' deal on if you want to try them again. They're new still...

Otherwise Diamonds or JEs are both good too.

 

Thanks, but i think i'm off to a good start with my new paper weight collection now. Thanks for the info too.

Ken R.

 

stay far away fom SRp's... other than that, just make sure your bearing tolerances are a little looser on the new motor and run a heavier weight oil. thats what kills the lt1s in the first place

 

Just be sure to get #2618 rather than the high silicon #4032 alloy for the pistons. Any piston designated for blower or nitrous use should use the #2618 anyway. But it pays to know what you are shopping for. As far as brand, there are numerous good choices, JE, Ross, Diamond, Probe, Lunati, etc. all make nice pistons. I have had good results and good service with JE over the years. Just a bought a custom set for my race car and they were very helpful.

Any good set of rings will probably be fine, but the "Hellfire" rings are specifically designed for boost and nitrous and work well. If you are going to boost and nitorus route, you might want to talk to the piston manufacturer about an upgraded wrist pin. But stay away from lightweight/taper wall pins.

Rich

 

Thanks for the info guys.

Ken R.

 

Are 4032s bad for boost? Whats the advantage of 2618s?

thanks

 

It might be a little early for me to say this, but probably not; don't get Speed Pro rings. I have two broken JE pistons from my supercharged 396, and it looks like it may be the fault of the rings. The chrome plating on the outside of the compression ring was flaking off. Part of the rim on the ouside of both pistons came off and it looks like the ring stuck to the wall and popped it off.

Maybe it was a little early to say they're bad rings; rskrause pointed out that with my supercharger spitting oil there will probably be detonation, so nothing is going to hold up so well under that.

 

The #4032 has ~12% silicon, a "eutectic" alloy. #2618 is a low silicon alloy having ~0.2%. For comparison, a hypereutectic piston has >12% silicon. There are advantages and disadvantage to each type of alloy. Briefly, a HE piston is great for general street use due to cost, durability, dimensional stability, and so on. #4032 is a good choice for general performance use including small amounts of boost or nitrous. #2618 is preferred for very high compression NA and large boost or nitrous situations. Obvisouly, the piston needs to be designed a specific purpose. A very light weight #2618 piston will not stand up to boost nearly as well as a #4032 piston designed for boost (thick crown, deep ringland, etc.).

Rich

 

FWIW, I'm doing (for the 408) Wiesco Forged Turbo Pistons, Childs & Albert Fire Power rings, Clevite 2199H main bearings, CB663 H rod bearings.

THe builder told me that combo will be virtually bulletproof. Esp w/ those rings.

 

Just to clarify one thing in my previous post. I was trying to say that the design of the piston is as important, or sometimes even more important, than the material. For example, just because a piston is constructed from #2618 alloy doesn't mean it will be a good choice for boost or nitrous. It might be a lightweight design with a tight ring package and lightweight tapered pins optimized for high rpm NA use and quite unsuitable for boost. And, of course, both the design and the quality of the material can differ between two "blower" pistons of the same alloy. Do you think that a cheap, imported 4340 crank is as good as one from Crower or Callies? I hope you don't. Another example: I'd rather have a stock OEM SBC rod than any of the cheap "forged 4340" aftermaket parts.

Rich

 

^ not trying to jack.. ^ RS, were you referring to my post? if not, what do you think of those parts?

 

They are fine. Wiseco makes a good piston, though a bit heavy. I have used them in the past.

Rich