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Discussion Starter · #1 · (Edited)
I've been working on the new Pistons for the 2GR-FE Engine (Evora / V6 Exige) for about one year.
And there is a new special alloy from Mahle, which is not available worldwide from any other piston manufacturer.
After very long negotiations with Mahle (This special material will normally not sell to other customer), the company has now agreed to develop new very durable pistons from this special alloy, in consultation with me.
These pistons will have no oversize, only for new engines (up to 30,000 km). So for engines that should have a performance increase.

Almost all other pistons that can be purchased (e.g., Wiseco) use a 2618 Al alloy. This is also extremely durable. But this alloy has two major disadvantages.

- 1. No long-term wear resistance, because as no silicon (In unfavorable case, after 30,000 km German Autobahn wore out)

- 2.High thermal expansion, large piston clearance, piston rattling when cold.

For this reason, street high-performance engines used 4032 alloy forged, are mostly used for road operation. Because the material lasts a long time with little wear, 150.000Km are no problem.

The new special alloy from Mahle is stronger than 4032 Alu and about 50% more longtime durable (wear rate) than 2618 Forged Alu. See the table
The piston design is also changed. So that the ring grooves do not break anymore.

If I order more sets at Mahle, it will also be cheaper.
Is someone interested? I do not want to sell any parts, I do not make any profit, but I am looking for a purchase group.
Price not yet determined, approx. 1400,- to 1500,- USD including rings, bolts, coating.

Greetings from Germany

Here is some basic information about the standard aluminum alloys, forged.
Hopefully everything is written correctly :)

For many applications, cast pistons are used which cover the largest range of pistons used.
Increased power motors are often equipped with forged (pressed) pistons.
These have about 30% higher strength compared to cast.
Classification according to used alloy:

- AlSi12MgCuNi

This aluminum alloy has been the most widely used in Germany and international engine construction for many decades. It is used because of its characteristics in the series and racing area. By 12% silicon content very good sliding or wear properties of the running surfaces and piston pin bosses are achieved.
The strength is sufficient to be used with it also in racing use.
Turbocharged engines with 300PS per piston can be realized with sufficient piston head cooling.
Your biggest advantage over 2618 is the high achievable mileage without significant changes in geometry and high wear resistance !


Due to the higher proportion of copper and magnesium, a slightly higher maximum strength is achieved. Since silicon is completely omitted (which has a lower specific gravity than aluminum), it is a bit heavier. This alloy originally came from the aircraft industry and was introduced as a piston alloy by its good heat resistance and high mechanical strength.
Since 2618 does not have any wear agents such as silicon, it has to be tempered to a higher strength in order to achieve adequate wear properties. The method most frequently used here is called T6 and achieves the highest mechanical strength values. This material is predestined for high specific power conditions (Formula 1, Drag race). The pistons are changed after a relatively low mileage before any geometry change (e.g., clerance in the cylinder) causes problems.


** The Enforcer **
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You'll have to become a vendor here to sell parts.

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