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jhsiegle
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When converting to the Toyota W58 5 speed transmission will a one piece driveshaft work or is a 2 piece necessary?

NigelK
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Hi

The 2-piece propshaft is not necessary regardless of which gearbox is fitted. The PO had already replaced the 2-piece driveshaft on my GT while it still had the Getrag gearbox, and I had a new one-piece driveshaft fitted when I had the W58 gearbox fitted. No one really knows why the JH5 and GT had the 2-piece propshaft - I read somewhere that JML encountered a vibration issue during testing with the Getrag box and ordered a job lot of 2-piece propshafts and centre bearings (I think these are Austin Maxi derived) as a fix. But then the vibration issue went away and JML decided to use up the parts it had already ordered to save money.

Best wishes,
Nigel

gmgiltd
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Hi Nigel,
I believe that the reason for the two piece driveshaft is that there is very little lateral support at the back of the Getrag box. The Maxi was front wheel drive if I remember correctly and I believe that the centre bearing came from the Marina/Ital 1700/1800.
Gordon

NigelK
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Hi Gordon

You're quite right, the central bearing was from the Marina. I read also that the Getrag box has a fixed rear flange, so the centre bearing was one way of accommodating fore and aft movement from the diff, the alternative option is to use a one-piece propshaft with a sliding front joint.

Have a great Xmas and New Year!

Best wishes,
Nigel

jhsiegle
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Thanks Nigel. I have another question moving further back in the drivetrain. My question is regarding the use of the 3.45:1 vs 3.73:1 rear end with the W58 tranny. I have also increased my horsepower with a 2.2 stroker crank, 10:1 pistons, 104/107 cam combination and lightened flywheel, and I am wondering whether the increased power can compensate for my current 3.45:1 rear end or whether Iwould be better off with the 3.73:1. Any ideas?

NigelK
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Opinions differ on this question. I think with a stock engine, the 3.45:1 diff and W58 gearbox combination is too tall. But my engine is also stroked to 2.2l and with the extra power (184bhp peak at 6750rpm) and torque (167 lb-ft peak at 5000 rpm) my GT is nicely driveable. But then again I'm not using it for competition, just for enjoyable drives on winding A roads. And I have a nice tall overdrive 5th gear for the motorway and still plenty of torque in top gear for overtaking...

Last edited on 12-26-2015 11:33 pm by NigelK



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