Mud-club

Vehicle & Technical => Range Rover => Topic started by: fishlocust on October 25, 2009, 19:05:15

Title: RR Classic automatic to manual gearbox conversion, with Chevy engine
Post by: fishlocust on October 25, 2009, 19:05:15

Hello,

I’ve only just joined so I’m a bit of a novice.

I was wondering whether anyone has any experience of automatic to manual gearbox conversions?

I have a 1989 Vogue, with a full Overfinch conversion, and the engine bored to 6.0. It has been reshelled into a 1994 soft dash shell, but with the original Overfinch engine and 4 speed automatic. The second car was air sprung, but it now has the Overfinch coils.

I’m very keen to work out what I will need, and what the best box, would be for this conversion.

Any help / thoughts would be very much appreciated.

Nick

Title: Re: RR Classic automatic to manual gearbox conversion, with Chevy engine
Post by: ben-dent on October 25, 2009, 20:14:50

personally i would keep the box thats on it, as it has the right gearing and is strongenough to kope with the overfinch engine power,

a manual will get chewed to bits with the big engine

Title: Re: RR Classic automatic to manual gearbox conversion, with Chevy engine
Post by: trecfive on October 25, 2009, 20:15:41

Quote from: fishlocust on October 25, 2009, 19:05:15

I was wondering whether anyone has any experience of automatic to manual gearbox conversions?
 Overfinch engine and 4 speed automatic.
what the best box, would be for this conversion.
Any help / thoughts would be very much appreciated.
Nick

Why try to reinvent the wheel. 6LTR and an autobox.POWER,TORQUE,SMOOTH GEAR CHANGES,job done.

Title: Re: RR Classic automatic to manual gearbox conversion, with Chevy engine
Post by: J.D. on October 26, 2009, 19:15:33

As above, the ZF auto is the only gearbox which will take the extra power. An LT77 or an R380 will do, but will be more vulnerable to breakages and wear from the extra power.

Title: Re: RR Classic automatic to manual gearbox conversion, with Chevy engine
Post by: fishlocust on October 26, 2009, 21:46:41

Thank you very much for all of your advice on this.

Title: Re: RR Classic automatic to manual gearbox conversion, with Chevy engine
Post by: Range Rover Blues on November 01, 2009, 02:13:10

It might be worth checking WHICH ZF box is in there and if it had any upgrades.  The Ashcroft transmission website has details of the hp22 and 24 boxes plus what upgrades can be made to the 22 using bits form the 24.

The 4.6 P38 had the 24 as it's a stronger box.  Having damaged mine (it looks like) I'd advise you make sure the auto is in tip-tiop condition too.  I'd agree though that auto is the way to keep it, the manual box's aren't really up to the job and even a humble 3.9 can smoke a clutch quite quickly.

Title: Re: RR Classic automatic to manual gearbox conversion, with Chevy engine
Post by: Range Rover Ron on November 23, 2009, 14:06:18

My mate fitted a Chevvy to his Dico and eventually took it out as it was destroying gearboxes and diffs.

Title: Re: RR Classic automatic to manual gearbox conversion, with Chevy engine
Post by: Range Rover Blues on November 26, 2009, 00:18:44

Yes a manual box would probably be more severe to the transmission and axles too.