gt37vgt

Ok mahles' are too much .
pricing is never clear .
it looks like JE are a shade cheaper and i could perhaps jet coated tops for the same price as wosseners ...
I want 16v 104.7mm 9.5:1 (s2 head)
so advice please real price's real experence .
and wieghts alleged expansion rates and recommended clearances

Duke

I suspect you want alusil compatible pistons?
If so, I would only go with Wössners since they have a factory coating for this.
With JE you have to go with some generic 3rd party coating which feels pretty uncomfortable.

fast951

I have both brands.
I prefer the Wossner as they will build the pistons to my specs, and I trust their coating to work properly with the Alusil block. Price wise, with the coating added both brands are fairly comparable.
I'm using Wossner on both of my 16V engines as well as a 8V. I like the product enough to become a dealer.

Chris White

I have used both and prefer the Wossners.
You can get the JE’s in different alloys (4032 or 2618) that have different expansion rates. There are many schools of thought on which alloy is more suited to each application.

Wossners are a variety of the 4032 alloy and as such they have tighter wall clearance than the 2618 pistons – which means less piston slap on start up and a more consistent wall clearance.

The main things that I like about Wossner is their willingness to work with me on piston design – they produce engineering drawings for each and every piston I order. Wossner also has an Alusil compatible coating (complete with ‘official’ acceptance of the coating by BWM for their Alusil blocks).

On a less technical issue Wossner is better to deal with when ordering pistons. JE has a policy that you can pay extra (up to 40%) and be put in the head of the production line – that means that my ‘regular’ orders were being delayed to accommodate other orders that paid this extra ‘fee’. As a result JE pistons could take several months to get during the busy season. I just find that concept annoying.

JE is more focused on the domestic market where as Wossner is more interested in European stuff.

In reality both brands will function well, its more about the willingness of the companies to work with me to get the right design for each application.

Mike Lindsey

According to Mahle, 4032 Mahle is safe to 18 psi, and above that, they want to build you a 2618. Since
Mahle is pretty reputable and experienced, we feel that's a good decision maker. If your running lower boost, 4032 is fine. Above, use 2618. Wossner doesn't offer 2618. J&E only does 2618 and Mahle does both. Although Mahle doesn't call it 4032 as they have their own in house name for it.

So your boost alone may narrow your decision process quickly. We have used and sold plenty of all three brands and they all have their benefits.

As for coatings, we have had great luck with PC-9 on the J&E's and can say that with confidence having pulled a engine down at 10k just to look at the skirt coatings before we starting selling it. And we have had no bad reports in the 5 years since.

If your ordering Wossner, you better be dam sure you know what you want because you will be providing them "all" the specs. If you spec it wrong, they will build it wrong, and you own it regardless.

Our J&E's are streamlined to about 10 days from order time. Add another week if coated.

We have had all three companies build pistons and have a good working relationship with all three
and know what to do and more important, what not to do. We also stock quite a few piston sets.

Duke

I don't understand the Mahle boost level stuff. They only thing important should be the cylinder pressure and not boost pressure. On an inefficient engine 18 psi could result in 75 hp/cylinder. In a highly effecient 3.0l 16v turbo engine 18 psi could net the double. The cylinder pressure however would be very different. So Mahle says it's ok with 4032 on a 550 hp 4cyl engine running 17 psi but not a 300 hp 4 cyl engine running 18.5 psi?

Fabio421

This is a very interesting thread for me as I am looking for some 104mm alusil compatible pistons for a turbo 928 project. Please keep the info coming guys.

Mike Lindsey

You would have to ask that question to Mahle. But since nobody is going to know the actual cylinder
pressure, they may use boost as a more standard of measure instead.

marcoturbo

John, what sizes of Wossner pistons can you provide ? What is the price of a set ?

fast951

Marc, you can get just about any size for the 951. As I said, they are custom built to your spec. You get a drawing that you will review and approve prior to moving forward. Pricing should be taken off line.

George D

JE does their own piston coatings in house.

George

Duke

But as far as I know they don't have an alusil coating.
Using a generic skirt coating seems risky IMHO.

George D

Duke,

Seems like a fair assumption. My block was Nicom coated at uschrome. I don't have to run alusil, but we coated the pistons anyway for better cooling and hopeful easier movement while running.

Regards,

George

gt37vgt

As for the material thing I'm not sold either way as the only people who say 4032 is no up to is mahle perhaps in the interest to sell there other material wich may be 4032 .

both have nice taper bore pins?
it seems If i want a more custom spec with lots of changes the wossener is the way
But JE's for the high duty set up ....
hmmmm

Chris White

interesting to note that the stock pistons are a high silicone alloy (like the 2618 alloy). They seem to survive past 18 psi for a lot of the listers...