Ultimate ST thread

[lee88]

If you haven't seen it yet, nice short video (~5 min) of the Larousse TDF car after restoration by Historika.
https://www.youtube.com/watch?v=8XB4Vmg0p-8

[beh911]

^^^^That was nice. I had never heard the personal side of Larrousse and that car

[928cs]

Thank you for the link. I have copied it to the thread of this particular car.

[ZWEIRS]

Had this ST the magnesium 908 front callipers installed?

[lee88]

^^^^That was nice. I had never heard the personal side of Larrousse and that car

Indeed the story about the birth of his son and thus the meaning of this car and the TDF to Larrousse was news to me.

[Ernie W]

Need Help... The type 911/21 MFI engine, used 87.5 mm P/C Q: what is the piston/cylinder part number for the 87.5mm P/C set, I have a part number of 911.103.987.50 ? Can anyone verify this part number. Thanks...Ernie

[914-6gt]

Hello Ernie, I'm no sure if this will help in your research, but here it goes...

I will look for the p/n to see if I have it, but in the meantime here is a visual-reference of the 87.5mm MAHLE pistons and cylinders I had.






Hard to see, but the casting number should be 84 P 13











I also looked at my 1999 MAHLE Piston Casting Number Master List...



...and the piston casting '84 P 13' taken from my OEM 87.5mm ST pistons is not shown. At least not in this reference.







Here is what Freisinger shows for a p/n at his site.

[gled49]

What is the cylinders spigot bore for those cylinders. The last long stroke 2.5 I did had an unusual bore, needed 908 base gaskets. G.Led

[letsrollbabe]

Studying Paul Frere's discussion regarding P&Cs used in the 2.3L ST engines, he points out that the cylinders were still birals...cast iron with aluminum fins as used in production 911s. The pics posted above show nikasil cylinders, which were not used initially with the 87.5 mm pistons. When the factory developed the 2.5L ST engines, the short stroke version needed an 89 mm piston bore, which could not be done with the biral cylinders, so the 917 experience with nikasil cylinders was introduced in a 911 engine. I think nikasil cylinders were also used with the long stroke 2.5L, with pistons being 86.7 mm.

At some point later, all the 911 race Mahle P&C sets utilize nikasil cylinders, but not sure when that happened.

[Ernie W]

This is what I have...a full set of Mahle P&C's (rings, pins, clips) purchased about 30 years ago from Race Force. Porsche part number on the set, 911.103.987.50