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| | | | Joined: Aug 2010 Posts: 24 'Bolter | | 'Bolter Joined: Aug 2010 Posts: 24 | Has anyone successfully bolted the BW overdrive to the ol 4 speed SM420? | | | | | Joined: Jan 2001 Posts: 1,424 ODSS President | | ODSS President Joined: Jan 2001 Posts: 1,424 |
~ Cosmo
1949 Chevy Half Ton
Rocinante, like Don Quixote, he is awkward, past his prime, and engaged in a task beyond his capacities.
"...my good horse Rocinante, mine eternal and inseparable companion in all my journeys and courses." ...Don Quixote, Cervantes
"If you come to a fork in the road, take it."...Yogi Berra
"Rudeness is the weak man's imitation of strength." ...Eric Hoffer
| | | | | Joined: Aug 2010 Posts: 24 'Bolter | | 'Bolter Joined: Aug 2010 Posts: 24 | I did and have used the search function which is not very useful for this forum, it could use an update. I know there has been discussion about overdrives for the sm420 but maybe one specifically has asked about the BW Overdrive being used with an SM420 which no one replied to. | | | | | Joined: Jan 2008 Posts: 4,962 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,962 | I have been playing with BW overdrives for 50 years and have R10 and R11 back sections in my store room. I also have some SM420s. I have toyed with the idea, but I see no way of doing it without a lot of machine work. I think if I were to try to do it, I would start with a 4 speed with an open drive shaft and fabricate a nose section with with an input bearing on a shaft with a seal that would accept a companion flange. The nose section would have to include means to securely mount it to a cross member. I think making the OD unit into an divorced unit would be more doable than trying to attach the OD to a SM420. And then it would work behind any transmission with an open drive shaft. | | | | | Joined: Feb 2004 Posts: 29,846 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,846 | There's a much simpler way to adapt a divorced OD than using the BW unit. Look at the Laycock De Normanville unit that was used on Jag, Austin-Healey, Triumph, MGB, and other Brit sports cars. It is identical to the Gear Vendors unit that's being sold for 5 or 6 times the price of a used Laycock. It would be very simple to either adapt the Laycock as a bolt-on extension to the SM 420, or fabricate an input flange to make it a divorced unit mounted on crossmembers. The Laycock is hydraulically-operated, and has its own onboard pump. A simple toggle switch is used to engage/disengage it.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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| | | | | Joined: Aug 2010 Posts: 24 'Bolter | | 'Bolter Joined: Aug 2010 Posts: 24 | Guys Thank you for the great info! | | |
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