I was curious if you can just replace just one piston n terminators or do I gotta replace all 8 if one is scared up ...
installing just one piston?
- Thread starter gravey32
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Its always best to replace all 8 with a set of new rings after the block bore has been cleaned up and checked. If the bore isnt straight with proper cross hatching and piston to wall clearances then the rings wont seat correctly, the pistons could be the wrong size, you could get blow by and you will have to tear down the motor again.
If you replace the pistons then I would replace the bearings and have the rotating assembly re-balanced as well.
If you replace the pistons then I would replace the bearings and have the rotating assembly re-balanced as well.
What's a rough estimate with equal pistons cost?
Roughly 2K depending on options. That is if I have the machining done, assemble just the shortblock. I charge more to assemble the long block and degree cams etc.
Just parts would be a different story.
Reason I ask is cuz i took my cobra 2 shop cuz of overheating.. then they tell me bad head gasket, then my head is slightly warped...then one of my pistons is scarred.. so I'm basically just wanting it to get fixed!!! lol......... what to do what to do ..
This isnt a sales pitch even though it may sound like it.
Send it to me and I'll get the engine straightened out correctly.
Well they have it all apart n head is at machine shop! I was jus lookn for some advise on what 2 do... what's the cheapest route? Can you replace just one piston?....with the head being machined back 2 normal
Rebore and torque plate the block. Deck the block. Check the mains and install new main and rod bearings. Install matching pistons to new bore size for the correct piston to wall clearance. File fit the rings to new bore. Re balance rotating assembly. Install rotating assembly and replace all TTY bolts. Have the heads(Both) decked and cleaned. Install and degree cams and heads.
Done. lol
Haha! Thas a lot of info !! now can you bore one piston some while the others are still stock bore? Or doall have 2 be bord the same?....
Can you? yes.
Should you? Absolutely not.
A larger piston weighs more and changes the compression ratio. So you will need to have the rotating assembly rebalanced anyways.
It is always best to keep as much as possible the same.
Alright! Thanks for the info
A shop tells you a piston is damaged with the motor still in the car and running? Can I have the number I wanna buy a pair of their x-ray glasses..
No its apart, and the head is getting machined at machine shop And there was one piston that was scarred, so ima get new pistons I believe...
You can replace 1 piston but it's best you answer a couple of questions first.
1) How may miles on the pistons currently in the engine?
2) How hard was the engine run over that period?
3) Does the cylinder in question require an oversize piston? +.005 - .010 probably OK, anything larger time for a new set or can you get away with just scratching the cylinder with a flexi-hone and install the same size piston in the hole?
4) Do you know what the brand piston and can replace it with the exact same piston?
5) How much power is the engine making?
If it's a low mileage engine I would say it's a good candidate but not without risks. If a shop is doing the engine work chances are they won't match the piston weight with the existing slugs to make sure the engine is in balance (my pistons weighed 399 grams each. Imagine if someone introduced a 415 gram slug into the mix :uh oh
. Also the new found seal on that cylinder’s rings will be a little higher than the rest of the engine.
1) How may miles on the pistons currently in the engine?
2) How hard was the engine run over that period?
3) Does the cylinder in question require an oversize piston? +.005 - .010 probably OK, anything larger time for a new set or can you get away with just scratching the cylinder with a flexi-hone and install the same size piston in the hole?
4) Do you know what the brand piston and can replace it with the exact same piston?
5) How much power is the engine making?
If it's a low mileage engine I would say it's a good candidate but not without risks. If a shop is doing the engine work chances are they won't match the piston weight with the existing slugs to make sure the engine is in balance (my pistons weighed 399 grams each. Imagine if someone introduced a 415 gram slug into the mix :uh oh
. Also the new found seal on that cylinder’s rings will be a little higher than the rest of the engine.It has 93k........... its just my weekend toy! No serious racing!.....making 467hp...
Hmmmmm
With 93K on the slugs it may be wise to replace all 8. Most likely they are the OEM pistons. At your power level and how you are using the car If the cylinder doesn't need to be bored and you can just hone even with extra clearance (.002 -.003) then I think this will hold you over till you first major overhaul. If you have to touch the block with a boring bar bite the bullet and bore all of them to the next oversize.
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