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GU5 diff

Johns SLE

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1979 VB SLE 4.2 ltr Trimatic
Hi There, first time on this forum for me. I purchased a Vb Sle about 12 Mths ago to restore, nearly finished, done as close to original as possible. at this stage I am trying to work out my speedo which reads 114kph @ !00kph (actual) 3000 rpm. I believe I have a Bw diff 3.23 from all my research, as it has the hump in the backplate & a rubber plug. I am thinking this wouldn't have been an ex factory fitment as it appears they only were fitted to a VK in late production.Probably fitted the GU5 for a tower as the car had a towbar. To to get my speedo to read correct I will need to change the driven cog at the gearbox. Any clues how many teeth I would need to correct the KPH.
 

Johns SLE

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Lacksballs

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VK Group C Replica
1: Check the rear tyre size & ensure both are the same
2: Inflate the tyres to the correct pressure
3: Download a GSP app on your phone go for a drive on the highway, travel @ 100 kph (actual GPS speed) record your speedo reading, work out the difference between actual & recorded as a percentage, then change the drive gear to suit ie +5% or -5% etc...
 

Johns SLE

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Thanks for that sire01tmk , that has sorted it ,red 23 teeth comes out at 103.6, my diff is 3.23 so the would make it almost spot on. The 3.23 option was not on the list. Cheers
Back again sire01tmk , just a quick question you may be able to answer, what no of teeth were on the drive gog on the Trimatic 3 speed when they left the production line.
Cheers & Thanks if you can help
 

sire01TMK

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Back again sire01tmk , just a quick question you may be able to answer, what no of teeth were on the drive gog on the Trimatic 3 speed when they left the production line.
Cheers & Thanks if you can help
Sorry mate I wouldn't have a clue I got a th350 in the vk
 
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