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Gordon Norris
Prolific User
Username: crewes_missile

Post Number: 158
Registered: 2-2005
Posted on Wednesday, 27 April, 2005 - 17:39:   Edit PostDelete PostView Post/Check IP

Went for a (terrifying) ride in a friends 454 big block hot rod last weekend. (Imagine sitting at about roof level in the open air in a machine with the power of a jet fighter, and the handling prowess of aeroplane jelly) I counted the gearshifts and noted how nicely it stayed in the peak power band...6 gears in all. Thinking he must have a modern Mercedes or BMW high tech box grafted on I asked what brand of box was it?
A: "Turbo 400 of course-only thing that will handle the torque and hang together"
BUT, BUT I spluttered...
"Gear Vendors under/over-drive" he replied, "you'll never look back".

So, if you want 6 speeds to play with including overdrive in your RR/B, but retain (mostly) originality and easy conversion back to standard, have a look here: www.gearvendors.com

For anyone familiar with the old Laycock de-Normanville overdrives fitted to many post-war Brit cars, it's a similar idea brought up to date, and which bolts onto the tail of the THM 400 without any need for brackets etc (see installation section) Tailshaft has to be shortened, but if I were to fit one I'd keep my original shaft and have a new shorter one made (not expensive) to enable easy conversion back to standard.

I have absolutely no idea if it will fit in the tunnel under a RR/B, but it all looks to be fairly compact. (size of a coffee-can)

Pat Lockyer, this might be of interest for one of your "Super-Shadows". Once you've found out if it fits in the tunnel and tested it for us, please report back...

GN.
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Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 408
Registered: 9-2004
Posted on Wednesday, 27 April, 2005 - 22:55:   Edit PostDelete PostView Post/Check IP

Gordon have sent you a link on a simple better transmission when the bugs are sorted.
500bhp pulling 38 tonnes.
No auto changes of course.
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Gordon Norris
Prolific User
Username: crewes_missile

Post Number: 162
Registered: 2-2005
Posted on Thursday, 28 April, 2005 - 17:25:   Edit PostDelete PostView Post/Check IP

Interesting Pat. CVT's (Continuously Variable Transmissions) have been around for awhile now, and Honda even offer one in the Civic in Japan, and in their Hybrid Civic here. However, most of these existing designs have problems handling big torque/power outputs. The one you've provided seems to be otherwise. May be some time before we see it on the road though. Some other big names are developing CVT's also, so it's undoubtedly the way of the future.

I'd still like to see a Gear Vendors under/over-drive unit on a high power RR like one of yours though.

GN.
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Peter Colwell
New User
Username: peter_colwell

Post Number: 2
Registered: 3-2005
Posted on Friday, 29 April, 2005 - 05:45:   Edit PostDelete PostView Post/Check IP

<<existing>>

It has been this way for many years in some agricultural equipment, eg. header harvesters of the seventies used it. The engine runs at a constant speed to drive all the on-board ancillary processing equipment that must run at set speed, but the over-the-ground speed of the machine rises and falls according to need.

The systems used were purely mechanical al la DAF type, and very reliable. They transmitted huge torque figures.

Peter
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Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 413
Registered: 9-2004
Posted on Monday, 16 May, 2005 - 08:03:   Edit PostDelete PostView Post/Check IP

Gordon not quite cvt, infinitely variable transmission maybe an oil cooler,to the future with economy and speed looking good.