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Discussion Starter #1
I am about to order up some Motronic pistons/liners for my engine build, but seeing prices all over the map. Does anyone know if these all come from the same manufacturer or might part houses be getting them from different (and possibly inferior) sources?

Just trying to figure out if this is a "get what you pay for" situation or if all Motronic pistons out there are the same.

Thanks.
 

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Motronic usually refers to the flat top pistons fitted to S4 spiders with a nominal compression ratio of 10:1 and which more like 9.7:1. Look at the pictures of the ones that you are planning to buy. There is a thread from a dissatisfied customer who bought domed Motronics from Vick. They are most likely the nominally 10.4:1 pistons that are often referred to as Borgo's. Some knowledgeable people claim that the domed piston makes less power than the flat top.

There have definitely been two different versions of flat top Motronic pistons that have different sized rings.
 

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Discussion Starter #3
Yeah - I have gotten a couple bad parts of late, so wanting to be sure I am getting a good set of pistons from a reliable manufacturer. Interesting about the rings...that's the sort of trouble I am trying to avoid.

I am actually happy to just buy the "bottom end kit" available from Spruell and use his Total Seal conventional rings, but seeing prices all over the map for "Motronic" pistons makes me wonder if there are different manufacturers and quality differences as a result.
 

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I would take your best shot and then measure whatever you get carefully. I don't know if oem "Motronic" P&L sets are still available new.
 

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Crackie

I have a set of new montronic pistons and liners that I purchased from Alfaholics and have not used. I do not know the manufacture but I have used other pistons sourced from Alfaholics and they have always worked just fine. I have a set of new Hastings rings to go with them also. PM me with your e-mail address and I can send pictures. I am in Tacoma
not to far from your location.

Bill
 
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