Hello all.
Hopefully all you clever people can help me with this question...
I have just acquired a gearbox, A+ DAM2886 (big idle gear). I'm trying to figure out if it's a close ratio.
The layshaft is stamped DAM3??? It's not clear, but the bits of letter could read DAM3168.
The first motion shaft has a 17 tooth first gear.
Now.... I know the close ratio had an 18 tooth gear, 22G1040 on the A-series boxes, but did the DAM boxes also have this?
I have had loads of A+ gearboxes, but have never, ever seen a laygear on a 'normal' A+ gearbox with a DAM number stamped onto it, ever.
I just can't quite make out the full number on it, but it's defiantly DAM3???
So... What is this gearbox, close ratio or not.... oh, its was not on a 1275 engine, but it was from a bitsa engine that had some 1275 parts (timing cover, clutch housing), so not an original engine.
Discuss.....
Close ratio gearbox??
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- 1275 Cooper S
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Re: Close ratio gearbox??
The Late 1275GT had the A+ Close Ratio Gearset fitted. Same ratios as the all Synchro Cooper S.
The First Motion Shaft did take the 18 mm Needle Roller and was 18 tooth. This was a DAM3167. The Laygear took the 2 step type Layshaft, this was a DAM3168. The Laygears are fairly thin on the ground.
I suspect with your 17t First Motion Shaft, it's a standard ratio gearset, in A+, these had a DAM3169 Laygear.
The First Motion Shaft did take the 18 mm Needle Roller and was 18 tooth. This was a DAM3167. The Laygear took the 2 step type Layshaft, this was a DAM3168. The Laygears are fairly thin on the ground.
I suspect with your 17t First Motion Shaft, it's a standard ratio gearset, in A+, these had a DAM3169 Laygear.
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Re: Close ratio gearbox??
Hi Tim
I have a couple of standard 3 step laygears stamped DAM3169, don’t see a lot of them but they do exist. The close ratio A+ with A series tooth profile are the part numbers Chris has detailed, All close ratio have 18T first motion.
I have never seen A+ laygears, standard or economy with a part number stamped.
Regards Jason
I have a couple of standard 3 step laygears stamped DAM3169, don’t see a lot of them but they do exist. The close ratio A+ with A series tooth profile are the part numbers Chris has detailed, All close ratio have 18T first motion.
I have never seen A+ laygears, standard or economy with a part number stamped.
Regards Jason
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Re: Close ratio gearbox??
Hello Jason.Jason wrote: ↑Thu Jul 04, 2024 9:54 pm Hi Tim
I have a couple of standard 3 step laygears stamped DAM3169, don’t see a lot of them but they do exist. The close ratio A+ with A series tooth profile are the part numbers Chris has detailed, All close ratio have 18T first motion.
I have never seen A+ laygears, standard or economy with a part number stamped.
Regards Jason
Thanks for the reply, appreciate it.
It's definitely a 17 tooth first motion, counted it again and again. It was odd as the laygear is clearly stamped DAM3??? It just looked like a close ratio laygear, really odd as you say, I have NEVER seen a 'standard ' laygear with a part number stamped.
I knew it was not a close ratio, they are ALL 18 tooth. It's just a odd one....