Piston clearance, engine building

[ralleyquattro]

Hi guys,

For engine builders.
The alloy block I got has a bore of 79.5mm.
The Sport pistons are marked as 79.47mm.
The question is, is this proper clearance i.e. 0.03mm??
I looked online but have not found a definite guideline for piston/cylinder clearance.

I would like to order the copies of the piston from JE, but would like to confirm above before going ahead.

Thank you in advance!

Cheers

[chaloux]

JE will recommend a clearance depending on your application and chosen alloy, but it will likely be 3 thousandths or thereabouts.

As long as you know your bore they will make whatever you need. Going to hone as well or is it fresh?

[PRY4SNO]

Curious, why JE? Why not Mahle?

[chaloux]

Or wiseco, or any of the others?

[my2000apb]

mahle FTW

[ralleyquattro]

Does Mahle offer custom pistons?
Audi only had one SQ piston in stock, they are now NLA.
Looking for suggestions/experience.

Thank you

[PRY4SNO]

http://www.theprojectpad.com/viewtopic.php?t=281

From Mahle:

These would be a custom part for us
...
$1,320 for pins clips and rings , US funds.
10-12 weeks for completion
Coatings are included , skirt and pin and ring coatings come standard on every MAHLE piston.

Kind regards,

Jason Griffin
jason.griffin@us.mahle.com

[PRY4SNO]

I would have went Wossner for cost:value if I'd gone full custom on my stoker build, but I got a good deal on a stroker set up with Wisecos. Only difference, so far as I can tell, was that the Wossner pistons are fully built in-house in Germany, from forging to delivery. Mahle, while nice, were an expensive way to rock out an OEM sticker on a custom build.

In your case, however, I could see the appeal. It just feels right.

[audifreakjim]

I have been really happy with my wiseco pistons, and I think they are quite a bit cheaper than JE

[ralleyquattro]

http://www.theprojectpad.com/viewtopic.php?t=281

From Mahle:

These would be a custom part for us
...
$1,320 for pins clips and rings , US funds.
10-12 weeks for completion
Coatings are included , skirt and pin and ring coatings come standard on every MAHLE piston.

Kind regards,

Jason Griffin
jason.griffin@us.mahle.com

Wow, thank you for that, had no idea, will be emailing Jason ASAP..
I wonder if they can make it from an Audi P/N.. that would be sweet!

Cheers

[PRY4SNO]

I'd think if they didn't have the wherewithal to build off a PN a sample piston would do the trick

[ralleyquattro]

In contact with Mahle, they will find a set of original drawings and make me additional 4 from that. All they needed was the stmping code from the bottom of the piston which is 79P11+ for your reference.
If I had known I would never bother buying the one from Audi Tradition, it was twice of what Mahle will charge me.. :(
Oh well.

[scubagli]

It will make a sweet paper weight.

[my2000apb]

It will make a sweet paper weight.

YES!!!!!!!!!!!

get five fresh ones

[GTJeff]

It will make a sweet paper weight.

YES!!!!!!!!!!!

get five fresh ones

They might be using the same drawings but I bet there isn't a snowballs chance in hell they will completely match your piston.

[ralleyquattro]

They need the piston, they located the drawing for the blank but not the piston itself, so it's on its way.
Not bad, they will cost $220 each!

BTW I am dealing with another contact now:
Tony Ford
Phone: 1 (828) 650-0814
tony.ford@us.mahle.com