Jack Knight Twin Cam Heads

General Chat with an emphasis on BMC Minis & Other iconic cars of the 1960's. Includes information on MK1 Action days.
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rich@minispares.com
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Re: Jack Knight Twin Cam Heads

Post by rich@minispares.com »

Spider wrote:
Tupers wrote:Didn't most of them go to Japan? I'm sure there was a company doing JKD 5spd twin cam conversions over there.
Slightly OT here - the JKD 5 Speed Gearboxes were also fitted by Rover to I believe 60 Mini Coopers, there was an inital run of 50 somewhere in the mid 90's then the last 10 off the line also had them fitted.
they where rubbish as well, the fifth gear gets all chewed up and there are no spare parts.

we are always getting people ringing up at work in the vain hope that parts from the minispares five speed will fit!
should you wish, you can contact me on rich@minispares.com

'long beard boss'

Tim Harber
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Re: Jack Knight Twin Cam Heads

Post by Tim Harber »

rich@minispares.com wrote:
Spider wrote:
Tupers wrote:Didn't most of them go to Japan? I'm sure there was a company doing JKD 5spd twin cam conversions over there.
Slightly OT here - the JKD 5 Speed Gearboxes were also fitted by Rover to I believe 60 Mini Coopers, there was an inital run of 50 somewhere in the mid 90's then the last 10 off the line also had them fitted.
they where rubbish as well, the fifth gear gets all chewed up and there are no spare parts.

we are always getting people ringing up at work in the vain hope that parts from the minispares five speed will fit!
We did sort a Jack Knight 5 speed box a while ago by getting a selector fork made, which wasn't cheap but it saved the box. I think one is supposed to advertise the fact if one is in business , but it seems to have missed me. We also sorted one of the prtotype ones that had no oil feed to the centre of the layshaft

Image

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bill773mini
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Re: Jack Knight Twin Cam Heads

Post by bill773mini »

rich@minispares.com wrote:
Spider wrote:
Tupers wrote:Didn't most of them go to Japan? I'm sure there was a company doing JKD 5spd twin cam conversions over there.
Slightly OT here - the JKD 5 Speed Gearboxes were also fitted by Rover to I believe 60 Mini Coopers, there was an inital run of 50 somewhere in the mid 90's then the last 10 off the line also had them fitted.
they where rubbish as well, the fifth gear gets all chewed up and there are no spare parts.

we are always getting people ringing up at work in the vain hope that parts from the minispares five speed will fit!
It's odd but I hear how terrible the JKD 5 speeder is all the time, can't be fixed, chews up 5th etc.

My SPI (the same one that's done Blyton now twice (I hope you'll agree not driven gently), the Italian Job and about 12k hard road miles mostly in 5th) has never given any grief despite a big chunk of torque going through it, the box it's self is a total joy, it's the nicest Mini box I've ever used.

Had the original 2 pin diff pop on the way back from the 2007 IJ, drove it slowly all the way home with a broken diff, pulled the box out and found it full of shrapnel and the diff cover cracked. Put a cross pin in from Rich and had the box rebuilt as a precaution as the diff was in such a mess. No problem with the rebuild and nothing at all damaged in the box, just new bearings etc as a matter of course.



Great box. :D
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Spider
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Re: Jack Knight Twin Cam Heads

Post by Spider »

I don't know a real lot about the Boxes and haven't heard much about them either, but I did drive 998 a few years back that was fitted with one. I thought the shift was excellent, probably a tad better than the stock one and the ratios very well suited that engine (mind you, while it was a 998, it was a very refined Injected engine, pulled really well to the point that I could hardly believe it was only 998 cc). 850man has more details on the car, engine and gearbox, I think he recently overhauled the box in fact.

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rich@minispares.com
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Re: Jack Knight Twin Cam Heads

Post by rich@minispares.com »

bill


yours is the earlier straight cut one though......

its the later helical version that gives all the problems. they didn't make the fifth gear correctly and they just chew them selves to bits.

id guess that the big, heavy 13" rover wheels didn't help with the problem either
should you wish, you can contact me on rich@minispares.com

'long beard boss'

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bill773mini
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Re: Jack Knight Twin Cam Heads

Post by bill773mini »

rich@minispares.com wrote:bill


yours is the earlier straight cut one though......

its the later helical version that gives all the problems. they didn't make the fifth gear correctly and they just chew them selves to bits.

id guess that the big, heavy 13" rover wheels didn't help with the problem either

Oh I didn't know that mine was an earlier version, it's from 96. Good news for me then! :D

I revise my statement, straight cut ones are brilliant, don't buy a helical one, they're rubbish! Better? :lol:

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JohnA
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Re: Jack Knight Twin Cam Heads

Post by JohnA »

Our S Works JK Speed box was replaced under warranty by John Cooper Garages after self destructing at 1500 miles. The new box was obviously fitted without cleaning the metal out of the engine as at 17,000 miles I had to strip and rebuild it, new oil pump, new camshaft and crank bearings. The replacement box has now covered 25,000 miles and is getting ready for some attention

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Spider
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Re: Jack Knight Twin Cam Heads

Post by Spider »

Looks like this thread is also going the way of that damn cat,,,,,,,,,

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JohnA
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Re: Jack Knight Twin Cam Heads

Post by JohnA »

Meow :o

Richspec
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Re: Jack Knight Twin Cam Heads

Post by Richspec »

Does anyone know if the Twin Cam head bolted straight on or needed block work / supporting mods?
Wanna see what I'm playing with? Youtube Channel
Caution ;) may contain 8 Ports, Xe's and VTec's, I don't do standard!

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