Carpokes Porsche Forum

Interesting article about campaigning GTR 003:
https://johnstraub.blogspot.com/2012/02 ... acing.html

Bespoke GTR (only) engine block and cylinder. Porsche put some effort and $ into this project.

Were the cylinders separate like that from the factory, or are you sleeving it? Fantastic pictures!!!

Tom wrote: Wed Jun 19, 2024 9:36 pm Were the cylinders separate like that from the factory, or are you sleeving it? Fantastic pictures!!!

The photos show a new and untouched factory GTR block and one Nikasil aluminum cylinder. Both are from the spares that were included with the car. The cylinders drop into the lower crankcase and use a cellophane type seal at the bottom. The cylinder head clamps them in place via 14mm head studs. Note that the lower case half is integrated into the oil pan. The 100mm cylinders were manufactured by Mahle, the pistons are Cosworth, and the billet 2.5L crank has the standard 78.9mm stroke. I've brought two cylinder heads back to Maryland, so more pics and flow numbers will follow.
MM

Do you have any pics / specs on the crank Michael? Not often we get to see a bespoke forged crank for a 944.

333pg333 wrote: Fri Jun 21, 2024 10:24 pm Do you have any pics / specs on the crank Michael? Not often we get to see a bespoke forged crank for a 944.

Unfortunately, the GTR is 3 hours from me, so I can't visit as often as I'd like. I brought several components back with me, but crankshaft(s) are still in the Virginia shop. I'll likely visit the GTR next week, so I'll take pics of the crankshaft. There are two cranks on the shelf that are slightly rusted due to storage issues over the last 40 years. I'll try to resurrect them without turning any journals undersize, but we'll see.

Recent pics. Found the engine in the car is tired, spare engine was not stored properly, so having to go through it - wanted to be familiar with it too. Under the gun to have it tuned, tested, and run in Monterey in mid-August. Nice billet crank, Carrillo rods, Cosworth pistons. Pan (lower case half) has nice crank scraper and windage tray. Selected a NOS cylinder head for this build. Installed guides, valve job, new valves, ported under the seats to blend to existing ports. All very nicely designed/prepared by Porsche and Andial nearly 40 years ago.

Very cool, thanks for sharing. It is amazing how much effort was put into an engine that was used in such a short-lived project!

Amused by the "Mid-Atlantic Rovers ex valves" writing on the box in the last pic. I briefly delved into that world a few years ago with a 1970 Rover P6 3500S Lemons Rally car. Neat little aluminum V8 engines, with limitations. They weigh the same as a 944NA engine, though (about 370 lbs). That has always been one of my biggest complaints about the 944 engine, it is large and heavy for what it is . . . . but that's another discussion for another time

Please keep us updated on the progress of the GTR!

The history and engineering of these is fascinating to me and I'm guessing somewhat lost to the general Porsche audience and those unaware of the 944/951. Great background and photos. Thank you for the revitalization and updates. Tom's 000 article is a wealth of info.

Well said, Rob. ^^^