Piston Ring Questions for a 302...

POWER302

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Nov 30, 1999
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I want to put a new set of rings in my motor while its apart. Its a standard bore 87 5.0 HO with the factory forged pistons.. What are my factory rings sizes? 1/16 or 5/64? Also what is a good set of rings for a HCI 302 w/ a wet shot that has future plans for boost "I was looking at speed pros"? I want them to be file fits also.. What is a good ring gap that will be decent for nitrous or boost? And Last what is the difference between low and high tension rings I have heard about?

Thanks
Eric
 
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POWER302 said:
I want to put a new set of rings in my motor while its apart. Its a standard bore 87 5.0 HO with the factory forged pistons.. What are my factory rings sizes? 1/16 or 5/64? Also what is a good set of rings for a HCI 302 w/ a wet shot that has future plans for boost "I was looking at speed pros"? I want them to be file fits also.. What is a good ring gap that will be decent for nitrous or boost? And Last what is the difference between low and high tension rings I have heard about?

Thanks
Eric

should be metric rings sizes I think should have 4 rings instead of the older engines only had 3 if I am remembering correctly
 
The Speed-Pro's will be fine, plasma moly tops is what I would look for.

I would go .022 top and .024-.026 second ring...this will help the rings stay stable and prevent flutter, it will also help get the heat out inbetween the rings.

3 rings total top, second and oil ring (oil ring is 3 pcs) I can't remember the ring size off the top of my head I do more aftermarket pistons then stock.
 
the problem is !some! cars with Hypueretic (sp?) pistons and other earlier models are standard sized ring widths and the forged pistons in the 91 on up cars were metric ..


just my $0.02
 
BlackBaer5.0 said:
the problem is !some! cars with Hypueretic (sp?) pistons and other earlier models are standard sized ring widths and the forged pistons in the 91 on up cars were metric ..


just my $0.02


Yeah I've had 5/64, 5/64, 3/16 ring combos as well... the forged piston I pulled was from a 88 302 Mustang, it would be best to check yours with a pair of calipers though.
 
Rick 91GT said:
Yeah I've had 5/64, 5/64, 3/16 ring combos as well... the forged piston I pulled was from a 88 302 Mustang, it would be best to check yours with a pair of calipers though.

So we really have no idea what my ring thicknesses are.. I would like to order some rings before I pulled the rods and pistons out.
 
Most parts stores can get the rings next day or even same, it will take you atleast that long to get the old pistons and everything else clean.

Are you having the block honed?

Make sure the ring grooves are very clean before re-installing.