"hate this piston design"
#3206039
01/18/24 09:11 PM
01/18/24 09:11 PM
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Joined: Sep 2018
Posts: 170 West Palm Beach, Florida
Craig J
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West Palm Beach, Florida
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Last week I was going to sell the crank, rods, pistons, fresh machined 0.030 over RB block to make a 493, and a local buyer informed me that his mopar consultant 'hates' this piston design.
I am a curious why these won't work in an 87 octane street car RB stroker application. Sorry the pics are sideways... technology has defeated me on fixing that...
Thanks Craig
Last edited by Craig J; 01/18/24 09:21 PM.
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Re: "hate this piston design"
[Re: Craig J]
#3206044
01/18/24 09:52 PM
01/18/24 09:52 PM
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Joined: Oct 2005
Posts: 272 Anchorage, Alaska
metallicareload
enthusiast
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enthusiast
Joined: Oct 2005
Posts: 272
Anchorage, Alaska
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I have heard an engine builder say they don't like dished pistons they didn't elaborate why. With a quench pad, I don't see why they would be much worse than flattops?
440, 4-Speed, 3.54 1968, when Dinosaurs ruled the Earth
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Re: "hate this piston design"
[Re: jwb123]
#3206046
01/18/24 10:11 PM
01/18/24 10:11 PM
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Joined: Sep 2018
Posts: 170 West Palm Beach, Florida
Craig J
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For a low compression street engine what is wrong with them? What kind of pistons are they Cast, Forged, or Hypereutectic? Lot of guys don't like Hypereutectic type pistons, but for a street engine not an issue, most stock engines now have hypereutectic style pistons, many old part number cast pistons have been replaced with hypereutectic style pistons. Just have to set a couple clearances different. Heck, I have used them with good success in mild drag engines. next question is what kind of chamber? If it is a 906 style open chamber, I would not like them either, no quench, if using a closed chamber head then again what is wrong with them? Pistons are forged 2618.
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Re: "hate this piston design"
[Re: AndyF]
#3206068
01/18/24 11:52 PM
01/18/24 11:52 PM
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Joined: Oct 2005
Posts: 272 Anchorage, Alaska
metallicareload
enthusiast
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enthusiast
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Posts: 272
Anchorage, Alaska
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If they were designed for open chambers there would be some kind of pop up dome right? These look like every other Big Block stroker piston which have a quench pad on the intake side, and a dish everywhere else. I would think a quench area around the spark plug would be beneficial, but what do I know, I'm a filthy street guy.
440, 4-Speed, 3.54 1968, when Dinosaurs ruled the Earth
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Re: "hate this piston design"
[Re: Craig J]
#3206089
01/19/24 03:35 AM
01/19/24 03:35 AM
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Joined: Aug 2003
Posts: 43,257 Bend,OR USA
Cab_Burge
I Win
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I Win
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Posts: 43,257
Bend,OR USA
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Last edited by Cab_Burge; 01/19/24 03:36 AM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: "hate this piston design"
[Re: Craig J]
#3206187
01/19/24 01:26 PM
01/19/24 01:26 PM
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Joined: Dec 2006
Posts: 2,117 Byron, NY
W.I.N. Racing
top fuel
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top fuel
Joined: Dec 2006
Posts: 2,117
Byron, NY
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My guess is they don't like the grooves and trough cut in the OD. The grooves (as noticed in the pic) seem to be carbon collectors. Also noticed in the pic it looks as if there is a sharp edge at the face/OD interface
Last edited by W.I.N. Racing; 01/19/24 01:28 PM.
'01 P1500, Blown/Inj BAE,/Veney ,Bruno/CS2,Dana 60 '01 Dodge 3500 S Cummins Auto, Fresh air kit, 4" Exhaust, '05 Dodge Magnum R/T - Too Much to list '60 Willys CJ5 '01 International LPX - Project,DT466, Allison '64 Plymouth Valiant, Inj 528 Hemi, 2spd
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Re: "hate this piston design"
[Re: Craig J]
#3206197
01/19/24 01:44 PM
01/19/24 01:44 PM
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Joined: Jan 2003
Posts: 14,513 So. Burlington, Vt.
fast68plymouth
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I Live Here
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So. Burlington, Vt.
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Fundamentally, I like reverse dome/reverse step-dish type pistons…….. but I’m not loving the ring grooving on that particular set.
It wouldn’t keep me from using them though.
Icon shows the top ring land to be .350” from the top. Is that how far down those are?
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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Re: "hate this piston design"
[Re: AndyF]
#3206277
01/19/24 05:25 PM
01/19/24 05:25 PM
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Joined: Jan 2003
Posts: 14,513 So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
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So. Burlington, Vt.
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There is def something “not good” going on at the top edge.
Last edited by fast68plymouth; 01/19/24 05:26 PM.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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