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no164ford
12-02-2005, 10:25 PM
I think are cars from the factory are some were around 8.1:1 CR. And I was woundering if any one now stocks good pistons to raise the compression ratio with out haveing to pay 600+ for custom pistions? What is a NA 3.8 compression ratio? I would love to try something around 9.1:1-9.5:1 forged or coated.

CMac89
12-02-2005, 10:29 PM
I'm more than sure that the Sealed Power .020, .030, and .040 over are 9.2:1 CR.

They are around $27 a piston coated.

white95v6
12-02-2005, 10:52 PM
I'm more than sure that the Sealed Power .020, .030, and .040 over are 9.2:1 CR.

They are around $27 a piston coated.

forged ones?? or the junk ones?

no164ford
12-03-2005, 12:21 AM
I'm more than sure that the Sealed Power .020, .030, and .040 over are 9.2:1 CR.

They are around $27 a piston coated.
Are these mustang pistons? Do you have there link?

CMac89
12-03-2005, 12:46 AM
Yes they are used for the mustangs too, but mainly it's for a 3.8. I found a picture from http://moranav6racing.com/category.html?CategoryID=21 but you would have to call Summit or Jegs and tell them a bore size to order them. I had a machine shop order mine and they were about $30 total.

They are hardened hypereutectic pistons which are good until about 500 or so rwhp. Maybe more. They are actually pretty decent pistons.

Hock
12-03-2005, 12:49 AM
I just got these pistons, they look good, and they are hyperutectic, not forged. They are good pistons for daily driving and they will handle some good power. Forged, as I take you have seen for our engines are better but IMO not worth the price unless you are planning to run alot of nitrous (i.e. >125hp shot) or are planning on building a real high power engine. If you want to check these out online go to http://store.summitracing.com/ and put in this part number in the search STL-H675CP-50MM.

super red91
12-03-2005, 04:11 AM
I just put the sealed power pistons in my new motor. They have a rough casting on the top of them and I took an hour or so to smooth the tops of them off. Not a bad piston for the price though, they should handle the power just fine as long as you have a good tune and no detonation.

no164ford
12-03-2005, 10:50 AM
These will work on 94/95 rods right, they have a grove for the snap ring. Also did you use rings for regular sc pistons or did you have to get them for that piston?

CMac89
12-03-2005, 01:22 PM
They will work on 94/95 rods fine. I got the Sealed Power .020 over pistons in my motor with the .020 over Total Seal gapless rings. Total Seals are great and only leak 1% with 1,000 miles on the shortblock.