924Board.org

[morghen]

If he's going to use a 944 style aluminium torque, perhaps since he's going to use a VW 1.8t..a VW gearbox would also be an interesting option if those gearboxes hold and offer the ratios he needs/wants.

Cheeky me pushing for that coupler i designed to be used
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Supercharger and EFI kits
https://www.the924.com

[MikeJinCO]

Ok, I'll change my tune. If space and finances not an issue save all the original pieces so that the next owner can spend $150K turning it into a museum piece. Find a donor 931 and rebuild everything. There are several tranny specialists who post on Pelican Parts Board, Rebuilding torque tubes appear to be more a pain to do than difficult and drop in either a 1.8t or build a modern 931 motor using US head components and ACM followers, rods, pistons along with modern ignition controls(Mittlemotor?) and fuel injection and the duplex cooling system that GTR's used tuned to a reliable HP and have a great time. That leaves a good base for a future restoration and provides a great ride. Yes, I left out a lot of details like turbo, clutch, etc.

Like I said before, trying to change the transmission just opens up another big bag of worms.
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Mike


'67 MG Midget Dp
'71 Ocelot Dsr Kawasaki 1000(under rebuild)

[Rasta Monsta]

Well, I only advocated selling the GTR box because Scott does not want to hurt or repair it. Therefore, it isn't useful.

The g31 boxes are plenty strong for this application. The original engine is already gone, so if the car is only for enjoyment, seemed like a practical solution to me.
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Toofah King Bad

• WeiBe (1987 924S 2.5t) - 931 S3

[Scott Sanda]

Love all the discussion!

I have enough 924 motor parts to build up at least 2 complete engines. What i don't have is any of the original turbo bits and pieces, etc.

So the idea of building a "modern" Audi 100 truck based turbo motor is intriguing and possible, but even with new tech applied, the cars had a lot of issues.

head lifting being one of them. Peter Dawe told me they used to actually machine the heads and use an extended sleeve that went into the head with a O ring seal.

He also told me they ended up actually sealing the water passages between the head and the block and running totally separate cooling lines for each.

And they still blew up. So my guess is everyone who has one in original form and runs it has it way detuned, which is fine, and certainly fun.

Remember they were pushing 500+ HP out of these. Fastest things on the track until they popped.

Even a mild build on original equipment, say 300HP would be a hoot in vintage terms.

I'm stupid. I want to go faster. So replacing the 3L Na with a modern turbo capable of easily sustaining 250 HP/L fits what i want to do.

But I'm never going to make so many changes that it cannot be put back into "normal" form at some point. Probably right before I die, so my kids have some inheritance, since I plan on spending any available money

[Carrera RSR]

Engine option.......proven in historic racing to deliver 395bhp, which is plenty enough for a lightweight 924 tubular chassis https://www.mittelmotor.de/racing/de/webshop/69044/6549/924-944/4-10-rennsport/4-01/2-4-01057-neu-detail Not cheap, but everything you need in a bolt in package.
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1980 931 - forged pistons, Piper cam, K27/26 3257 6.10 hybrid turbo, 951 FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife
Now www.924board.org/viewtopic.php?t=34690
Then www.924board.org/viewtopic.php?t=31252

[Rasta Monsta]

[Cedric]

I think you can expect good reliability with a 931 engine at the 400hp mark, as Joakim has proven over the years. The 1.8t would need a full bottom end build aswell, but have a better head as standard of course, but they need work to be reliable at high hp.

Do what you like best, any rolling car isbetter than a garaged one
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1980 924 Turbo
www.instagram.com/garagecedric/

[Carrera RSR]

[Mike9311]

Would be cool to scan the GTR trans....

My thoughts about some of the issues with the 2.0 are component weight and piston cooling. When I heard about how high these engines were/are revved, it blew my mind. Parts seem too heavy to handle those revs. I also have been dreaming of the best way to build piston oil squirters and hope to come up with this plan within the next month simply because I need them .
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1980 931 since 1989
1981 Ideola 931 Club Sport
1982 931 Entwicklungsfahrzeug
1979 924 NA ohne 650 mit 471
1982 931 Red Resurrection - 951 IC
1982 931 parts car / resurrection?
1980 924 NA (R&D lightweight)
1982 931 wana-be GTR race car

[Carrera RSR]

Mittelmotor 924 GTS spec car at Nurburgring - https://youtu.be/3hIfyjbLApM

Customer car on the dyno - https://youtu.be/aCvEAD2Aoew
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1980 931 - forged pistons, Piper cam, K27/26 3257 6.10 hybrid turbo, 951 FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife
Now www.924board.org/viewtopic.php?t=34690
Then www.924board.org/viewtopic.php?t=31252

[Scott Sanda]

https://youtu.be/kqwGx3ZDn-k Try this one for a fun dyno run.

[Carrera RSR]

Awesome. Was that the 944 motor?
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1980 931 - forged pistons, Piper cam, K27/26 3257 6.10 hybrid turbo, 951 FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife
Now www.924board.org/viewtopic.php?t=34690
Then www.924board.org/viewtopic.php?t=31252

[chuck21401]

[Scott Sanda]

technically a 968 motor. Finch cam profile, Mike mount built. KMR tuned.

[Fasteddie313]