Stu, I bought two five speeds when they were cheap. I boxed and placed them on the shelf till someone wanted them more than I did. As you suggest I went with a wide /spread ratio A+ gear set and a 2.76 CWP and added two OD drop gears. If you do the math it should come out as 2.56 overall FD ratio. Yes I have a 1360 Cooper S engine with a stump puller cam. No super charger but it's hard to pull off in first without wheel spin. Driving around town in the rain last week I could spin the tires in third with just throttle. Granted I only have 145 / 12s on 4,5 wheels. 3000 RPM is 70 MPH, 4000 is 94 MPH. It's possible to run 45 in 4th at 2000 RPM and it's very smooth doing that. I'd like to send all my gears ( every gear in the tranny ) out for REM treatment. That should take some of the FWD whine out of it. I'm currently building another gear box like it for a customer. I drove a 998 with a remote and 3.44 last week and at 70 MPH there is alot going on. 

I'm also thinking if I have to put up with that might as well take an old race 66 shell and install a 1071 S engine with a SC/CR gear set 4.20 Semi SC CWP on posi. Great for stop light GP and good for little else. Whats that? 42 MPH at 3000 RPM and 55 at 4000 and 104 at 8000 RPM.  Steve (CTR)

It sounds as if some of you are trying to create modern car performance/comfort levels with a load of machinery which struggles to achieve that. 

You want a 5 speed so you can go down the motorway at 90 at 2500 RPM, but at the same time, you don't want noisy gears, or a first which is like a second. The problem is that 5 and 6 speed boxes are made for racing engines. You want a 2.9 final drive AND a sensible first gear AND a sensible top speed. Then you want it to be quiet as well. 

Buy another car, a mini is not suitable for those things. 

A while ago, I stripped out the interior of mine and stuck a 137hp 1430 in it. It is not the sort of thing you drive around London in. 

Rather than trying to spend $20000 on putting racing car parts into an old mini, trying to make it a modern car. How about using a spread ratio (A+ helical box) a 2.76 final drive, a stumpy cam and a supercharger with a sensible amount of boost. Anything else seems to be highly unlikely, very expensive and quite disappointing. 

took me a little while to figure it out, yes i have a rod change box that is stock, you have to lift for reverse and also for 5th, but it goes in nicely. tried to use the KAD quick shifter but could not get it to function and after talking to heritage they told me their experience was that a quick shift kit would not work with a 5 speed.

jimfai, how does that Mini Sport unit shift? Any special work on the rod shifter?  My customer was expecting the 5th gate and reverse to be in line, but the design adds a separate gate for 5th.  Do you still have the 'lift for reverse' feature in the shifter?  We taked about building a "precicion shifter", but I have to get those gates to line up better first.

Let me say that I have no direct experience with Mini Sport, so only passing on my customer's.  After tearing down the increadible Arden crossflow head unit from the Austin America when the 5-speed was simply not driveable, he tried repeatedly to contact Mini Sport with the intention of shipping the unit back to them in England for 'repair'. After a few weeks of silence from them, with the stunning show car and it's delicate bits dismembered all over his shop, I suggested a nice 4-speed in 3.44 or 3.21 with his 12 inch wheels.... I mean how fast do you want to go in an AA really?  

But what to do with the ebay 5-speed? The owner of the car is a true gentleman, and did not want to 'unload' the problem box onto someone else. Perfect project for me and Cooper Road Mini!  I'm building a jig to mount a shifter and will try to make it shift with satisfyingly crisp detents into all the gear positions with no gears in the box... like I did with the 4-sync magic-wand unit I built for the Super-Moke.

A couple of comments, The 'real' JK 5-speeds were straight-cut and used few if any of the DAM5626 assemblies, so yes noisy!  The aftermarket ones should not be... they mostly use the standard A+ single groove helical gears, so maybe the 'noisy' unit had straight-cut drops or final drive.

A version of Jack Knight is still around, but not at all the same group.  I have a customer who did finally get a new 6-speed from them in the last couple of years after parting with an ABSURD amount of cash and waiting an absurd number of YEARS!!  It's made from a 5626 case now.  We still don't know how or if it works!

The arithmetic says a 3.1 and standard ratio makes 1st gear pretty close to 3.44 and close ratio - Close ratio means a taller 1st.  But from there each successive gear is further away, so bigger RPM drops all the way to 1:1 4th.  But I absolutely agree, it's the best way to give most Minis versatility for US roads.  The main downside is one few people understand.... The taller 1st makes more clutch slippage necessary for our hot rods, and most of these Minis will have an annoying "bucking" getting off the line and in reverse as cluch-chatter sets in. Try taking off in 2nd for a week with your "normal" car. It won't like it!

my woodie wagon with the specialists components 1350 with a 16v head was fitted in the uk with a mini sport 5 speed box when built, i have not driven it an excess of miles but i do like the 5th gear and have not found the box to be any louder than a standard one. it was built 8 years ago and mini sport is still selling and servicing them, they were very helpful when i had some questions for them about it too.

As l understand it, Jack Knight is no longer in business but there has been several (2-3) successors to the business (Do not relate the word successors to the word successful)

In fact one poster to this board, ex USA citizen now living in the UK, used to refer to the Jack Knight gears as made from "chocolate"

Now, my 5 speed set up is something else, 1380cc,Fuel injected, Super charged and of course the 5 speed-

Who needs V-Tech power ??

BIG AL

I had a MS unit in to rebuild a few years ago. Quite a clever design with part of the assembly turning into. a dismantling tool as the parts get stripped out. The main problem appeared to be the layshaft which was made in two parts that screw together. This design appeared to have a lot of flex judging by the damage to the gear case cause by this movement. 

just what i had in mind Kev!

My 2c-

For a road car, just fit a 3.1 diff and stock gears (not Cooper S closer ratio). This gives you approx  S ratios in 1-2-3, and a taller 4th gear.

dido what jemal said.. and very noisy. 

nope 5 speed was optional and agree with Jem, Jack knight was da s**t they still got them in their catalogue

Great info thanks guys. But didn't the 1990 ish Rovers all come with 5 speed transmissions? 

 

Now THOSE 5-speeds were the 'real' Jack Knight units with there own case disigned from scratch, and for the most part were quite fantastic. I installed a very few of them on my engines prior to about 2005 when the supply dried up.  Still not the greatest shift quality unless your rod linkage was perfect, but much better than the 'aftermarket' variety.   By aftermarket, I mean the ones using modified DAM5626 housings with custom machined components to 'graft' in 5th gear and linkage for shift forks.  

That's where the one I have goes sour.  Poor attention was given to the cobbled-in linkage. When lined up to engage the "extra" 5th gear fork, the selector lug is still engaged in the 3rd & 4th gate, so either it won't go to 5th, or it slams back into 3rd... simply unacceptable.  I'm going to try shimming the stack of "fingers" that make up the shift gates and pricision align them with the lug controlled by the shifter, looking for a nice click into each gear position. If you want to look at my innitial assessment of this Mini Sport unit, here's the Cooper Road Mini R&D basement:

i once read about a guy that worked for cooper garages in the 90s, that said they only installed 5speeds to about 20 cooper sports as optional equipt.. Honestly i'm of those people that look for the 5th gear when driving my mini but its the cost that keeps me away..

Not hard to find but EXPENSIVE.... and for your nearly 5 grand, the shift quality is generally god awful... you think a standard Mini has a stick in the mud?

BUT.... stay tuned!  I have a MINI SPORT unit a customer got on ebay, and I'm trying to 'gunsmith' the linkage to make the thing shift.  Mini Sport wants no part of it.... the last thing they want is to get into a unit they may have sold years ago, when they no longer deal with the company they contracted with to machine the parts.  That brings up another big problem... where do you go for parts?  Many of these were tiny runs of a few here and there, and unless you have a machine shop in your basement, they become a boat anchor!

Also people imagine that the extra gear will miraculously give the car longer legs, but these little engines just won't pull it. They have to spin to make power, lugging them simply destroys the THREE main bearings!

I'll post here or on my CooperRoadMini.com my progress!

Are 5 speed transmissions hard to find?

Are there problems that are specific to rhe 5 speed transmissions?

is it worth money?