Mahle piston compatibility

[vegashelipilot]

I'm rebuilding the engine on my '69 2002 with 121 head.  I found these on eBay.  Mahle 082 09 01 (1st over, 89.265). Wondering if these would work with a similar compression ratio to the stock flat tops I currently have.  

Also, can I re-use the wrist pins from my current pistons as these don't include them, just rings.

Thanks guys.

[tech71]

They will work with the 121 head provided  its servicable

[tzei]

If old engine hasn’t totally blown then i think you can use old wrist pins (and locks). They usually have no wear on them. Light oil & snug fit - if not, bin. Rod top end bushes you may wanna do.

[tech71]

I'm watching the same pistons among others.

I have purchased from this overseas seller twice I think with no issues, shipping was fairly fast

[tech71]

1 hour ago, tech71 said:

They will work with the 121 head provided  its servicable

I would make sure (tear down pressure test) your head is ok for use before pulling the trigger on the pistons.

 Heads can develop cracks between water jacket and combustion chamber and 121 121Ti seem to crack fairly frequently.

Start with #3 combustion chamber

First thing to do is clean up the mating surface and look closely,  use a strong light and magnifying glass. Many times you can spot cracks before dropping cash to have it pressure tested😉

Edited June 21, 2023 by tech71

[vegashelipilot]

Awesome thank you. These flat tops should be compatible with any head (121, e12, e21) should I need to find another head, correct?

[tech71]

12 minutes ago, vegashelipilot said:

Awesome thank you. These flat tops should be compatible with any head (121, e12, e21) should I need to find another head, correct?

Thats correct but compression ratio will be lower with them, both have larger combustion chamber volume than the 121 head.

Not sure I would want to mate them with an E12 head, compression will most likely be  below 8.0 : 1

Edited June 21, 2023 by tech71

[Son of Marty]

58 minutes ago, tech71 said:

Not sure I would want to mate them with an E12 head, compression will most likely be  below 8.0 : 1

Perfect for a turbo, here the one I would use.

[TobyB]

Is your block currently un- bored?

 

1st oversize was usually only found in factory rebuilds,

and while it leaves enough room for some cleanup, a really

worn or significantly scarred block may not clean up at only 

.12mm per wall...

 

t

 

[vegashelipilot]

Yeah good point, not pulling the trigger on any pistons until the machinist takes a look.