ring gaps

[workingdan]

I am putting my motor back togeather and was wondering on ring gaps.I am running .030 over speed pro Hypereutectic ZH521ACP30 pistons with speed pro ZE434K30 moly rings. I did a search and have been finding .019-.022 for the top ring and .021-.024 for the second ring. I check were they are at now and I am finding .010-.017. So I am going to have to file them. I have not found anything on the oil rings. Is the gap on the oil rings important?

 

[charlief1]

http://www.turbobuick.com/forums/engine-tech/274490-speed-pro-moly-ring-gaps.html

 

[workingdan]

Ok I saw that post but it dose not say anyhing about the oil ring gaps. Also what kind of gap should i have from the piston to cylinder wall?
Thanks

 

[charlief1]

The manufacturer should have given the specs to you when you got them and the machinist should have set them to spec. As far as the oil control rings I'd set them to stocks specs.

 

[workingdan]

The manufacturer should have given the specs to you when you got them and the machinist should have set them to spec. As far as the oil control rings I'd set them to stocks specs.

My machinist set them to manufacturer specs but that is only .001 to piston/bore. That seems way to tight.

 

[turbofabricator]

Open the top gap .002" MORE than the piston manufacturer specs. The second gap .003"-.004" MORE. Hyper pistons NEED lots of ring gap, or they can pull the top of the piston off. Hyper pistons run MUCH hotter than a cast or forged piston requiring higher ring gaps. Too much gap is MUCH better than too little. The difference in power between a .018" gap and a .025" gap is imeasurable. BUT......a tight gap WILL kill your new engine.

 

[charlief1]

I didn't know that Ken. Thanks for the info.

 

[workingdan]

Open the top gap .002" MORE than the piston manufacturer specs. The second gap .003"-.004" MORE. Hyper pistons NEED lots of ring gap, or they can pull the top of the piston off. Hyper pistons run MUCH hotter than a cast or forged piston requiring higher ring gaps. Too much gap is MUCH better than too little. The difference in power between a .018" gap and a .025" gap is imeasurable. BUT......a tight gap WILL kill your new engine.

They didnt give me specs for the ring gaps. I was thinking .020 top ring and .024 on the 2nd.
What do you think?

 

[turbofabricator]

Sounds good for a 3.800"-3.830" bore and Hyper pistons. Debur the rings after gapping with a jewlers file or a fine stone. I use a small cylinder hone stone. They're cheap and easy to hold onto. You can buy them for about $8 at any parts store. (replacement stones).

 

[workingdan]

Sounds good for a 3.800"-3.830" bore and Hyper pistons. Debur the rings after gapping with a jewlers file or a fine stone. I use a small cylinder hone stone. They're cheap and easy to hold onto. You can buy them for about $8 at any parts store. (replacement stones).

Cool Thanks