trying to identify aftermarket 340 Pistons

dbphemi

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I’m trying to identify these aftermarket 340 pistons from a 30 year old build. the casting number is 1029p . I had the short block rebuilt when i was in high school. I don’t remember specs . I remember the guy taking me into lowering compression ratio to run pump gas. Probably because i was a broke kid who couldn’t afford new forged pistons at the time had something to do with it lol. If anyone can identify these pistons that would be awesome, Thanks!

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RustyRatRod

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Appears to be the stock cast late 72 and 73 low compression piston.
 

dbphemi

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I know they are not stock because i had it bored .30 over. i’m trying to figure out the brand maybe the specs. I’m trying to decide if i want to open the can of worms of changing them out forged stock style pistons for my 69 340.
 

ch1ll

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Alot depends on the heads your going to use, iron or aluminum and chamber size. Me personally I would not use them.
 

Professor Fate

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I know they are not stock because i had it bored .30 over. i’m trying to figure out the brand maybe the specs. I’m trying to decide if i want to open the can of worms of changing them out forged stock style pistons for my 69 340.
Stock replacement +.030 cast pistons. Looks like it could be an old Sealed Power number.
 

RustyRatRod

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I know they are not stock because i had it bored .30 over. i’m trying to figure out the brand maybe the specs. I’m trying to decide if i want to open the can of worms of changing them out forged stock style pistons for my 69 340.
They are stock STYLE. The fact they are .030 over means nothing except for their size.
 

dbphemi

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ok ,thanks for the help. I am planning on running the stock x heads . I’d like to go back to 100 percent stock but i’m not sure how it will run on todays pump gas. we have 93 in illinois mixed with 10 percent ethanol.
 

MoparMike1974

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Could be stock replacement badger or sealed power.
Those typically net around 8.5:1
 
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33IMP

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That number doesn't show up in my 80s vintage TRW catalog.
As others have said, sealed power, or badger.
For the new pistons, check out UEM, Keith Black, Icon, Silvolite (all tye same company) One of their lines will have something you like.
Edit: Silvolite are cast, KB are hypereutectic, and Icon is the forged line.
 
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Bewy

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I do not think the aftermarket used the steel strut, only Chry.
 

RustyRatRod

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ok ,thanks for the help. I am planning on running the stock x heads . I’d like to go back to 100 percent stock but i’m not sure how it will run on todays pump gas. we have 93 in illinois mixed with 10 percent ethanol.
It will be fine with those pistons, because these engines always measured lower on compression than they were rated. It will be in the 8.5-9:1 range.
 

ch1ll

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Your in Illinois? Contact Hughes engines and discuss your engine with him. He can help you chose pistons and a cam to run with your x heads and pump gas. Compression, cam bleed off and your overall performance expectations.
 

408 swinger

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Measure the compression distance. Center of pin to top of piston. I have seen "hybrid" 340 pistons that have four valve reliefs like the low comp pistons, BUT, have the comp distance of the 10.5 piston.
 

krazykuda

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I’m trying to identify these aftermarket 340 pistons from a 30 year old build. the casting number is 1029p . I had the short block rebuilt when i was in high school. I don’t remember specs . I remember the guy taking me into lowering compression ratio to run pump gas. Probably because i was a broke kid who couldn’t afford new forged pistons at the time had something to do with it lol. If anyone can identify these pistons that would be awesome, Thanks!

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How to Check Compression
 

Jadaharabi

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So after all these years these Pistons were doing a terrible job and now you want to replace them?
As for Dave Hughes I would not ask him the time of day. Unless you got your checkbook out and are signing him a check when you ask him.
Jmho that I highly value.
You may quote me. I'll stand behind my opinion.
 

dbphemi

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So after all these years these Pistons were doing a terrible job and now you want to replace them?
As for Dave Hughes I would not ask him the time of day. Unless you got your checkbook out and are signing him a check when you ask him.
Jmho that I highly value.
You may quote me. I'll stand behind my opinion.
The engine hasn’t run in over 20 years . The engine had lots of problems, wiped cam lobe , low oil pressure, damaged main and rod bearings. i’m weighing my options because the engine i built when i was 17 is probably not the engine i want when i’m 48 .
I’m trying to figure out what i have before i go buying parts. i’d rather not use any modern aftermarket parts because of the lower quality of the china parts that’s out there now a days.
I’d prefer to find .030 over chrysler pistons get it re balanced and put it all stock .
 

plumkrazee70

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The engine hasn’t run in over 20 years . The engine had lots of problems, wiped cam lobe , low oil pressure, damaged main and rod bearings. i’m weighing my options because the engine i built when i was 17 is probably not the engine i want when i’m 48 .
I’m trying to figure out what i have before i go buying parts. i’d rather not use any modern aftermarket parts because of the lower quality of the china parts that’s out there now a days.
I’d prefer to find .030 over chrysler pistons get it re balanced and put it all stock .

If the motor had that many issues, I would suggest having the block checked out first to be sure your bores are still true and .030 replacements can be used. Nothing worse than assuming and then having it all go wrong.
 

dbphemi

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I’m aw
If the motor had that many issues, I would suggest having the block checked out first to be sure your bores are still true and .030 replacements can be used. Nothing worse than assuming and then having it all go wrong.
Im aware, the cylinders don’t look that bad surprisingly, just a little scuffing. it had very low miles on the rebore. the cam and bearing damage were all caused by my stupid mistakes. I unknowingly dropped the coil terminal nut in the distributor hole when switching to electronic ignition and it fell into the cam and chewed up a lobe. years later i bought a new cam , tore it apart cleaned it out the best i could and put in new oil pump . at that point the bearings were good no signs of wear. when i fired it up oil pressure was at at 80 psi for couple seconds and then dropped to 10 and stayed at 10 . I took the engine back apart and the oil pickup was loose and the bearings were scored.
 

ch1ll

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So after all these years these Pistons were doing a terrible job and now you want to replace them?
As for Dave Hughes I would not ask him the time of day. Unless you got your checkbook out and are signing him a check when you ask him.
Jmho that I highly value.
You may quote me. I'll stand behind my opinion.
I’ve talked to he numerous times and I haven’t spent a cent.
 

Jadaharabi

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I use to sale him cores. Untill he screeed me out of over $1200. He can go to hell for all I care. Very unchristian of me but maybe I might forgive the greedy sob someday.
You go right ahead and keep on dealing with him there will be a day when he breaks it off in you. I have no doubt. Unless you keep paying him that'll what keeps him happy.
 

ch1ll

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Of course he wants to sell you something, he is in business to make money. You may not like his personality but I have not heard anyone complain about his parts and combinations that bought from him. There are parts that I prefer over his like rocker arms and lifters, but the parts he sells are quality parts. He knows what he is talking about and has good combinations. If your not a do it your selfer and don’t have a solid path to an engine you will be happy with and performs like you want it to, you need to find and trust an experienced mopar engine builder.
 
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