924Board.org

morghen · Joined: 21 Jan 2005 Posts: 9014 Location: Romania

No words, just grateful you share this with us.
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Supercharger and EFI kits
https://www.the924.com

barnwerks · Posted: Thu Nov 02, 2023 12:28 am Post subject:

Good Lord!
It's going to take me a month just to study the photos from one post.
Amazing!

Mike9311 · Joined: 14 Dec 2004 Posts: 1786 Location: Chicago-ish

Britain, you know what you are really good at? Embarrassing the rest of us but I mean that in the best of ways...wow wow wow
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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

Raize · Joined: 18 Sep 2013 Posts: 281 Location: Scotland

Why do you think the oil pump gear failed?

Britain · Joined: 26 Nov 2013 Posts: 303 Location: Cornelius, OR

Raize · Joined: 18 Sep 2013 Posts: 281 Location: Scotland

Cedric · Joined: 27 Aug 2004 Posts: 2721 Location: Sweden

Britain · Joined: 26 Nov 2013 Posts: 303 Location: Cornelius, OR

Okay...I know it has been a hot minute since I have updated this thread...so here a comprehensive update.

Starting from the broken oil pump gear. We determined that most likely cause of the broken gear was a separated harmonic balancer.

To address this, we went to a place in Cali that rebuild harmonic balancers (Dampener Doctor) so I sent them our failed units. They strip out the old elastomer (rubber) and make them new again. Much better than 30years old parts and fantastic turn-around.

As with the old chassis, the front end of the car unbolts...making engine swaps fairly quick.

We also finished up the rest of the bodywork including the floor, side skirts, and carbon front valance.

Britain · Joined: 26 Nov 2013 Posts: 303 Location: Cornelius, OR

With the new chassis ready to go, we ran the 2023 Thunderhill Championship. There was a mirror racing incident that happen during a restart in the rain that left the front bumper, headlight valance, intercooler, radiator, and some other misc structure damaged. We were able to repair the car enough to continue running, but it took us out of contention.

I also cut the video from the incident for your viewing pleasure. https://www.youtube.com/watch?v=Zc0gwyX0BAk

That incident resulted in another rebuild of the front-end and some rear to the diffuser.

Britain · Joined: 26 Nov 2013 Posts: 303 Location: Cornelius, OR

Next up was a race at The Ridge in April'23. Car was looking good.

However, we had another oil pump gear failure...this time in our #2 engine and a slightly different failure mode. The oil pump gear drive flange sheared right off...but you have to take into account that these parts are now 30years old and have untold amount of mileage before we starting using them. Fortunately, there is a guy in Europe making upgraded billet gears made and we replaced the gear in both engines to prevent future failures.

Engine reassembled and ready to go back in the car.

Britain · Joined: 26 Nov 2013 Posts: 303 Location: Cornelius, OR

Our rear wing has been on the car for over 8 years and has seen better days. I found this APR wing from a BMW that had the clear coat coming off and figured I could make it fit. I stripped off all of the flaking clear coat and removed the mounting plates. I then made some new mounting plates to be able to retain our existing uprights, made some modifications, and all looks good.

Britain · Joined: 26 Nov 2013 Posts: 303 Location: Cornelius, OR

The 924 is always the best it has ever been...until it isn't. This is the 2nd time that the car is working really well and then collides with an immoveable object. Such is racing.

In-Car View:
https://www.youtube.com/clip/UgkxRzVvriC6qQ1nRCnMHSIUpVXP7PFe7bY2

Outside View:
https://www.youtube.com/watch?v=W_nyKcywCH8&feature=youtu.be&fbclid=IwY2xjawHRU5xleHRuA2FlbQIxMQABHdzsWanlGfdkOX9WF-T4XKieEkIdlXmrz7MKC4mskOLqfikAvuOiUnlzEA_aem_Y5S1-rPBfcnm2q-u82amCw

The impact with the wall was ~1.5g at 51mph. The spin dissipated a lot of speed/energy and reduced the impact. We got lucky with only the rear hitting the wall as a frontal hit would of resulted in significantly more damage.

Britain · Joined: 26 Nov 2013 Posts: 303 Location: Cornelius, OR

Unfortunately, the damage was deeper that it initially looked.

I pulled all of the damaged parts off the car and cut the mangled sheetmetal. Fortunately, the damage appears to be mostly behind the fuel tank area and didn't hit the trans/diff cooler or the fuel pumps. The passenger side frame rail will have to be chopped off and the rear of the car will need a new clip.

The plan was to take the car for an alignment, however the rear suspension inner pick-up point is bent and will have to be repaired before I can put it on a rack. This will involve pulling the trans, the fuel tanks, and the rear suspension...then I will build a fixture off another chassis to get everything back in place.

I pulled the car apart to start rebuilding in the rear suspension mounts. To properly locate the inner mounts, I built a fixture off a spare torque tube that bolts to the car.

Britain · Joined: 26 Nov 2013 Posts: 303 Location: Cornelius, OR

Not the best pictures...but the rear suspension inner mounts fabrication has been completed.

Britain · Joined: 26 Nov 2013 Posts: 303 Location: Cornelius, OR

Rear suspension mounted and all appears to be in the right place.

Rear frame horns capped off and ready for a bolt-on rear clip. Had to cut off more of the rear-end...but sometimes you have to go "backwards" (into a wall) to go forward.

And now with the fuel tank and mechanical bits put back in place.