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txtypes said:
compression tet done,,,i was worried...
195
205
195
205

leak down passed aswell,,,i have element block 27k: je 12.5:1 coated skirt
and i just dropped hem in. as jeff stated low mileage nonabused blocks dont have this problem

under certain circumstances this thread would be true...at the moment wth just dropping them in its running like a champ
its good that the numbers are all consistant with each other, but isnt that pretty low for a 12.5:1 CR motor
 

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JDM96SpecCTR said:
its good that the numbers are all consistant with each other, but isnt that pretty low for a 12.5:1 CR motor
it all depends on his cams... the actual ratio doesnt mean much compared to other engines, especially not when we are talking a custom built race engine here.

mine was pushing 245psi but that was with stock type S cams.
 

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Discussion Starter #104
it really depend on what you use to measure it... as long as the readings are consistant.. On the same motor with the cheap autozone crap, I have seen 160 across the board, and 220 on a sears gauge
 

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ok I am gettin a k24 element motor and I ordered cp stock replacements 85mm I believe... Am I gonna have to send these back in replacement??? What advise and recommendations would you give someone with a k24 bottom on ordering high compression pistons with no intensions of boring/honing???
 

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dadonn said:
ok I am gettin a k24 element motor and I ordered cp stock replacements 85mm I believe... Am I gonna have to send these back in replacement??? What advise and recommendations would you give someone with a k24 bottom on ordering high compression pistons with no intensions of boring/honing???

I recomend getting the right size pistons for starters. K24 stock bore is 87mm hence the title... :rolleyes:

Also you should take to a machine shop and have them check to make sure the bore is still within spec and doesn't need honing... Is it a used block or new? If new you'll be fine with standard 87mm's.

Did you read the thread at all?
 

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jon v said:
I recomend getting the right size pistons for starters. K24 stock bore is 87mm hence the title... :rolleyes:

Also you should take to a machine shop and have them check to make sure the bore is still within spec and doesn't need honing... Is it a used block or new? If new you'll be fine with standard 87mm's.

Did you read the thread at all?

yes your right my mistake. so Now I have an element block with unknown mileage walls have no scars however. The pistons I ordered are cp 87mm replacements, I am contemplating changing to 88mm and just bore the block to be safe. I am aware that the block might be good enough with no rounding as there is a good chance it wasnt beat on but isnt it safer to just bore it instead of taking the chance with it?? Further more even if your block is good enough to use the stock replacement drop in's arent they going to wear after a while?? With everyone so focused on not having to spend on sleeving/boring are you guys taking longevity into consideration???? car is going to be a daily driver and weekend track car so whats best for longevitiy in this situation.
 

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dadonn said:
yes your right my mistake. so Now I have an element block with unknown mileage walls have no scars however. The pistons I ordered are cp 87mm replacements, I am contemplating changing to 88mm and just bore the block to be safe. I am aware that the block might be good enough with no rounding as there is a good chance it wasnt beat on but isnt it safer to just bore it instead of taking the chance with it?? Further more even if your block is good enough to use the stock replacement drop in's arent they going to wear after a while?? With everyone so focused on not having to spend on sleeving/boring are you guys taking longevity into consideration???? car is going to be a daily driver and weekend track car so whats best for longevitiy in this situation.

good choice sir
 

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no this issue has been addressed.

most people are running 87.5mm bore with stock sleeves.

companies have designed new pistons for this all to work now. Before, when this thread was made 4+ years ago, it was a new thing.
 

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So in this resolvment, is the oem headgasket out of the picture now? Or is it safe to use it on a .5 over liner?

I see other companies offer .5 over and 1mm over, what are people using?
 

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i have a question, why in the world would anybody want to just "drop" pistons in without knowing piston to wall clearances or any other clearances for that matter. These are probabaly the same people who take the stock bearings off their rods and place them in the new rods wih out ever measuring anything.

took the words right out of my mouth as im reading this. i cant beleve someone would throw pistons in a used engine without going oversize , i dont care how old the thread is , people have been building engines for 100 dam years. how they wear based on composition and rod stroke ratio is not new. basic engine knoledge and common sense here is all that was ever needed really.


you can use a stock headgasket on a .5mm overbore yes. but no more imo.
 

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Got this information off Hotwheelz:

12.5 Cp 87mm pistons don't work in k24 blocks

k24 blocks have 5 thousands for factory pistons, forge units only allow 3...

So k24 blocks would need 88mm.

87mm will ruin the skirts. in no time
If I run a stock block and aftermarket pistons I should go 88mm
 
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