Mahle Mystery Pistons - Calling all experts

It appears to me that the piston on the left would probably be an early design piston and the one on the right would be a later design. I guess that by the skirt shape and the area under the oil ring. The piston on the right is also 20+ grams lighter I bet just by the shape, I'm guessing. I ran into a similar problem on F355 engines. The pistons in the engine had a slightly different shaped skirt, and the newer replacement pistons also weighed 19 grams more!! Further investigation by David at Ricambi showed that any pistons that didn't meet weight at the factory were sent out as replacement parts. As a result, we designed our own pistons-- better and lighter than factory pieces too, and cheaper. Depending upon how many pistons you need, you may have to resort to custom pistons too. In the Ferrari 180 degree flat plane crank, it is very important that all pistons weigh the same to keep the engine in balance. If you can't find a suitable replacement, PM me and I can give you a quote on custom pistons if you want.

 

ya know whats so funny, i have found out that many out of spec and downright wrong Lamborghini parts from the assembly line were boxed and shelved for "service parts".

now, 20 years later, when we are trying to keep our cars running, we find new old stock parts, that were garbage when they were new, and the supply of any good parts to be " 0 ". that explains why Lambo Jalpa wheel bearing are almost $700.00 EACH, and SKF and lambo "locked" the part number so you cannot get replacements.

lucky for me Diablo bearings with factory shims will work in a Jalpa.

so these small quaint Italian "craftsmen" did have a bit of Redneck in them after all.



LOL

 

I'm not clear on why one style is "right" and one is "wrong" as long as all 8 are the same.

Better than stock pistons are available from JE and others for less than OEM price.

The biggest reason for the scarceness of Jalpa parts is the small number of cars built (411) and they haven't developed much of a following.

Strut cartridges have been rare almost since the beginning.

 

If needing only a single piston or two, you may want to contact Dave Helms... he may have what you need too.

 

KEVIN ---

As with many out-sourced parts, you often get the supplier's (Mahle) id stamps and the end assembler's (Ferrari) stamps on the same part. Plus, with cast / forged parts, there are often id's for the "as cast / forged" version and id's for the final "machined" part --- this can be a source of confusion when trying to determine which part id to match to a replacement.

If you wish, send me a PM with as much "Mahle" info & identification stamps (plus everything else that's on the piston) as you can find, and I'll run it by a friend of mine who works for Mahle --- he may be able to hunt this down for you.

No promises though, as he works for the Filters Division of Mahle... but, he might know whom to contact internally.

 

This is my first post on this site. I got an Email yesterday from Williws telling me I need to join and check out this question. The 81P #s are the numbers of the forging. The 81 is for 81 mm diameter, the "P" is for forging (as opposed to an "L" for a casting or a "V" for a casting with steel struts), and the last digits are the "derivative" of that diameter. The "8093" is the last 4 digits of the finished print of the piston. What you don't know though is the change level difference if any. The numbers above the "M" tell you that this piston was machined at the MAHLE Rottweil plant (plant 5). The "04" is a MAHLE plant internal number that identifies which shift and/or which machine line. The "0184" says that it was machined in January of 1984. I think more importantly in this matter is the 2K31817. I am suspecting that this number is the first part of the drawing number. I will inquire to friends in Germany today to see if I can get prints that reference each forging type. Hang in there and don't stray to the dark side. Piston precision is toleranced tighter than parts in a Swiss watch.

 

What a small world.....

I was born in Rottweil, my mom was working as an administration secretary at the Mahle Plant.

Today my cousin is working at Mahle in Stuttgart (administration too). I gonna ask him if he can help.

Good luck, Till.

 

Sorry Kevin, no help here.

Dave

 

I'm sure it does refer to a USA version Ferrari engine application....great thread here!

308 engine pistons were all used up long ago in rebuilds of the 'oil burners' so we can use this Factory support!

Thanks again to those, joining in......

 

KEVIN ---

It looks like between "208vol" and "till", they've got you covered. So, I won't bother to ping my buddy at Mahle afterall.

 

there is a VW, (front wheel drive) that uses struts that fit the Jalpa.

ill be quiet and not distract from the thread.......

 

cool post, and welcome. its refreshing to see others help those in need, especially with parts for these crazy cars!

 

Kevin i "think" the USA spec cars were at a lower compression ratio and had a dished piston as opposed to the rest of world spec cars due to the emissions requirements. i could be mistaken, but it seems the "euro" cars of the same type, always have a higher compression ratio and require a higher fuel grade. then there are the camshaft profiles....

 

I think you might have heard this from me.

Not a perfect fit, I've modified a few sets though.

 

I just mailed all the information to my cousin at Mahle.

He told me that Ferrari-pistons are distributed in the so called "Motorsport"-department which is splitted from the normal aftermarket
That's why it is impossible to choose Ferrari as manufacturer if you visit: http://www.motorenteile.mahle.com/eLIZA/app/queryEngine

Now we have to wait for answers.............

Oh man, in 1984 I lived only 500 meters away from the place where this piston was made.
Today I live 500 m away from Mahle headquarter in Stuttgart.
There must be a solution.

Best, Till.

 

The times I have seen "red dot" and green dot" markings on pistons, it was to differentiate between bore clearances. For example an 81mm piston that actually measures 80.996 mm will be within tolerance, but require a smaller bore than an 81.004 piston, hence the red and green dots. That was not on Ferrari pistons, though, so take it for what it's worth. Also, I am picking numbers otut of the air; it's been a while, but I seem to rem pistons coming in 0.01 mm increments.

 

First information from my cousin at Mahle:

He transmitted the photos to the technical service. The competent engineer promised to look after our problem.

My cousin wont be in his office until wednesday 13th of march (skiing in Austria, lucky man). So don't worry if there are no news until then.

Best, Till

 

That's great news - been a fun thread to follow and look forward to how this all turns out.

 

Adeptel, I still have more technical information on its way. I may be able to elaborate more after tomorrow. I am glad you have what you need on the way. As for til.a.fischer, you must live on Pragstrasse or Haldenstrasse. I was just there at the end of January, and I too had to make a trip to Davos / Klosters (Switzerland) for some snowboarding over the weekend. The motorsport part of MAHLE is located in Fellbach. There is also a motorsport division in the USA, but it is primarily focusing on Domestic (USA) racing - and quite successful I might add.

 

Adaptel,

great that the problem is solved.

208vol,

my office is indeed more in the center of Bad Cannstatt, that's the other side of the Neckar (river). But tomorrow we are moving....horrible mess, everything in boxes.
I didn't know that the Motorsport-part of Mahle is in Fellbach. My occupation is in architectur, my links to MAHLE are stricly familiar.

Am I correct assuming that you are working for MAHLE?
Davos is also a nice place to be. Growing up I spent some summers there.

I think we are all interested in more technical information on the topic.

Best, Till.