gear box question (AGAIN)

[gandolf]

I have the 1.6 engine & c6bp gearbox with 10" wheels.I wanted better mpg and quieter motorway running. I have bought a box from rover 25 2lt td for a 3.6 final drive .Have I made a wrong buy?

[CooperWorks]

I love my C6 gearbox on 10 inch wheels.
What are you wanting to achieve?
If to keep acceleration but better causing surely just changing your fifth gear is the answer.

I'm sure the more knowledgable boys will be along soon to shoot me down

[AGoaty]

If you have bought the Rover 25 2.0 diesel box then that will have a 3.9 final drive. It's code is S6. It is a U spec box which has stronger bearings on the main shaft.

The box is not a straight swap. The bell housing is different.

With your current C6 box and the S6 box you can swap the bell housing over and make it fit. I did this on Phoenix.

I agree, motorway driving was perfect. You get around 3000rpm at 70mph. It does slow the acceleration slightly though as the K series likes to rev. You may find it is great for cruising but having the 1.6 may be a bit over kill.

If you want to do this, I can post a link to gearbox rebuilding. Was very helpful when I did mine.

Garv, you cannot just swap the 5th gear. The main shaft holding the 5th gear is splined differently. You need the full S ratio set. Even if you could, 1 to 4 would be great but a huge jump to 5th so would be silly.

Others on here have built a C7 ratio box. Basically you need 3 boxes to do this. The bell housing from your C6, the 3.6 final drive from a Freelander diesel and the gear set from a MG ZS 180. Revs drop about 200rpm at 70mph from the C6.

Another alternative is a Freelander 1.8 petrol box. This has a wide ratio gear set and a nice cruising 5th. This box fits straight on. +++EDIT+++ No it doesn't.

http://www.16vminiclub.com/showthread.php?t=38011

[gandolf]

Originally Posted by AGoaty

If you have bought the Rover 25 2.0 diesel box then that will have a 3.9 final drive. It's code is S6. It is a U spec box which has stronger bearings on the main shaft.

The box is not a straight swap. The bell housing is different.

With your current C6 box and the S6 box you can swap the bell housing over and make it fit. I did this on Phoenix.

I agree, motorway driving was perfect. You get around 3000rpm at 70mph. It does slow the acceleration slightly though as the K series likes to rev. You may find it is great for cruising but having the 1.6 may be a bit over kill.

If you want to do this, I can post a link to gearbox rebuilding. Was very helpful when I did mi
Garv, you cannot just swap the 5th gear. The main shaft holding the 5th gear is splined differently. You need the full S ratio set. Even if you could, 1 to 4 would be great but a huge jump to 5th so would be silly.

Others on here have built a C7 ratio box. Basically you need 3 boxes to do this. The bell housing from your C6, the 3.6 final drive from a Freelander diesel and the gear set from a MG ZS 180. Revs drop about 200rpm at 70mph from the C6.

Another alternative is a Freelander 1.8 petrol box. This has a wide ratio gear set and a nice cruising 5th. This box fits straight on.

http://www.16vminiclub.com/showthread.php?t=38011

Thanks Andy another£60 wasted Ill look for the freelander box.

[InstantCustard]

Originally Posted by gandolf

Thanks Andy another£60 wasted Ill look for the freelander box.

In your original post you said you wanted better mpg and quieter motorway running, the S6 box will be fine for that, you only need to swap the bellhousing.
3000rpm at 70mph and slightly wider gearing, there is a drop off when you use 5th but how often do you use 5th when your playing?
Getting a Freelander box and messing around will give you about a 200rpm drop at 70mph, that’s not that much.
I’ve got Andrews old S6 ratios because I like the way it dropped off in 5th for motorway journeys and the slightly wider ratios means I’ll drop a few revs between gear changes but I don’t see that as an issue.


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[CooperWorks]

Originally Posted by AGoaty

If you have bought the Rover 25 2.0 diesel box then that will have a 3.9 final drive. It's code is S6. It is a U spec box which has stronger bearings on the main shaft.

The box is not a straight swap. The bell housing is different.

With your current C6 box and the S6 box you can swap the bell housing over and make it fit. I did this on Phoenix.

I agree, motorway driving was perfect. You get around 3000rpm at 70mph. It does slow the acceleration slightly though as the K series likes to rev. You may find it is great for cruising but having the 1.6 may be a bit over kill.

If you want to do this, I can post a link to gearbox rebuilding. Was very helpful when I did mine.

Garv, you cannot just swap the 5th gear. The main shaft holding the 5th gear is splined differently. You need the full S ratio set. Even if you could, 1 to 4 would be great but a huge jump to 5th so would be silly.

Others on here have built a C7 ratio box. Basically you need 3 boxes to do this. The bell housing from your C6, the 3.6 final drive from a Freelander diesel and the gear set from a MG ZS 180. Revs drop about 200rpm at 70mph from the C6.

Another alternative is a Freelander 1.8 petrol box. This has a wide ratio gear set and a nice cruising 5th. This box fits straight on.

http://www.16vminiclub.com/showthread.php?t=38011

Yeah, thought so

[AGoaty]

At the end of the day, it depends on its use. If you are spending a lot of time on the motorway journeys then the S6 is the best option. This does mean stripping 2 boxes and rebuilding them though. Not everyone wants to do that.

Dan is right. From the C6 you have now, swapping to the Freelander petrol (S4), in 5th is about 200rpm drop. The S6 will drop 200 more.

The gearbox is not too complicated to build. Lots on here done it.

Shame you are so far away or would offer to help.

I helped Will on here via Facebook video call. Worked very well!

Here's the link. It's for bearing replacement but shows very well what is required to strip and build the box. I can do this now in under 2 hours. Obviously more for your first time.

http://www.rovertech.net/forum/viewt...4792482ac3076f

[gadget555]

If you do do it yourself be very careful of the 5th gear baulk ring/selector ring they have a nasty habit of falling off as the are not held on by anything when you have the box in bits, If it does come off it will go back on both ways! but there is only 1 right way and you also have to make sure that the baulk ring has seated on the 3 little dogs, it look's like you have it all in the right place to put it back together then you put the top casing on and open the big circlip the casing should just drop down to the other casing with a little hand pressure! if it doesn't the you haven't located the baulk ring on the dogs properly and you wont get it to close up without damaging the little 1mm spring ring that fits inside the selector ring, don't ask me how I know this as I bent 2 in 2 days Doh!

[ardonfast]

I'm beginning to wander about you k, searies is tops lot lol
Why don't someone start a firm makeing to finnished articacals?
A dead 5th gear sucks ,

[InstantCustard]

Originally Posted by ardonfast

I'm beginning to wander about you k, searies is tops lot lol

Why don't someone start a firm makeing to finnished articacals?

A dead 5th gear sucks ,

How often have you used 5th in competition Shaun?
The wider ratios on the diesel box mean 4th is capable of 110mph.


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[gadget555]

What he said above, plus I'm only changing up into 4th @ 90mph!

[AGoaty]

Originally Posted by ardonfast

I'm beginning to wander about you k, searies is tops lot lol
Why don't someone start a firm makeing to finnished articacals?
A dead 5th gear sucks ,

Shaun, the problem is there is so much choice. It depends on its use. I still think the C6 box is a good choice. But the OP doesn't. There are lower or higher geared options. I am running the C4, which is lower than the OP has. I think it's great. You cannot please everyone.

[ardonfast]

All roads in Devon are down hill,
All roads in Cornwall are up hill
Was only a pokey poke,
One day I'm Gunnar have me a vvc
But I won't want a lazy 5th that will go up to 150 mph
In a mini,
Is there just 1 box that bolts on and is similer to a mini?
I'm not disagreeing but just tickling you rover boys nuts!

[MiniLandy]

I had a turbo diesel box on a 1.4 engine. Mad as a bag of cats in the lower gears, but pretty civilised in the higher ones.

For a road car, I thought it was great.

[AGoaty]

Originally Posted by ardonfast

All roads in Devon are down hill,
All roads in Cornwall are up hill
Was only a pokey poke,
One day I'm Gunnar have me a vvc
But I won't want a lazy 5th that will go up to 150 mph
In a mini,
Is there just 1 box that bolts on and is similer to a mini?
I'm not disagreeing but just tickling you rover boys nuts!

Shaun, all of the gearbox choices are higher geared than most Mini's. The G4 box has a close ratio set but with 13" wheels has top speed of 110mph. It's what I originally had in Phoenix. You would love it.