Changing the gearbox, do I want to do the clutch too...?

[Corranga]

I think I know what most of the advice here is going to be but...

I have a B4BP CR box to replace the standard C6BP in my S1.

The clutch in there an AP Racing from Elise Parts, but it's been in maybe 5 years. In that time I've covered less than 25k miles.
The car is a slightly breathed on standard (stage 1 head, bigger valves, standard cam, 4-2-1 + k&n) so probably has an optimistic 150hp.

Am I risking it too much by trying to save 230+VAT on a new clutch?

Can I find a compromise by just replace the drive plate (assuming you can buy them separately)?

Edit: Anything else I should consider doing at the same time?

Thoughts?

[Stu160]

I would change it.

Stu

[BiggestNizzy]

Me too, And stick a lightened flywheel on it to.

[mwmackenzie]

Yeah AP Clutch, drive shaft seals, Lightweight flywheel, Linkage kit form moto build, braided hose and a slave should eliminate the need to work in the area again could be costly but worth it.

[woody]

Take it out, inspect it and replace if required. At 25k in 5 years with that power it should last you a while longer, potentially another 10 - 15 years at that rate.

The standard clutch I removed at 68k was in fine condition with the 160 engine. What's the thinking behind the gearbox swap? I looked at it when I had a C6BP sitting but concluded there was no overall benefit.

[Shug]

Agree with the Woodster on the inspect and replace if required route - the clutch on the K is massively overspecced for a light car. Mine only finally needed done after about 90K miles and some heavy shoeing (on a standard clutch), most of which with north of 170bhp and a lot of track. Check slave cylinder, make sure release arm is moving freely etc, of course.

Don't agree with the C6BP chat though - by far the crappest bit of the original S1 drivetrain. Diesel ratios and that horrible leap between 2nd and 3rd. B4BP is the box the car should always have had unless you want it as a motorway cruiser. I did it late in my ownership of the car and one of my regrets is not doing it much sooner.

[woody]

Agree with the Woodster on the inspect and replace if required route - the clutch on the K is massively overspecced for a light car. Mine only finally needed done after about 90K miles and some heavy shoeing (on a standard clutch), most of which with north of 170bhp and a lot of track. Check slave cylinder, make sure release arm is moving freely etc, of course.

Don't agree with the C6BP chat though - by far the crappest bit of the original S1 drivetrain. Diesel ratios and that horrible leap between 2nd and 3rd. B4BP is the box the car should always have had unless you want it as a motorway cruiser. I did it late in my ownership of the car and one of my regrets is not doing it much sooner.

Ah, had a moment of forgetfulness there. Ignore what I posted on the gearboxes as I got totally mixed up with the numbers.

[Stu160]

The release bearing changed for sure, thats the weak link.

[Corranga]

Yeah AP Clutch, drive shaft seals, Lightweight flywheel, Linkage kit form moto build, braided hose and a slave should eliminate the need to work in the area again could be costly but worth it.

I already have the uprated linkage kit from EP, as well as their uprated cables, and the braided hose was one of the first things I did to get rid of the red plastic one.

Oh, lots more questions now...

Can the drive shaft seals be done without removing the box?
I plan to strip down and POR15 the wishbones etc so might do it then (not sure when...)

Does a lightweight flywheel make much of a difference?
Would it make hills more of an issue (or is that my misunderstanding) any other cons?

I can justify trying to save 230 quid on a clutch with replacing it and the flywheel right...

I was planning to pay someone to do the gearbox switch (probably at the same time as a cam belt change) rather than attempt it myself, so unlikely I'll be POR15ing at the same time, and not sure I fancy trying a gearbox change on axle stands.

The release bearing changed for sure, thats the weak link.

I think the AP clutch come with an uprated release bearing 5 years back, so this will be the same 5 years + 25k max miles on it too.

[woody]

and not sure I fancy trying a gearbox change on axle stands.

I will be shortly, should be easier than the engine swap sans crane.

[robin]

I would replace the release bearing for sure, no matter whether was "uprated" 5 years ago; if you're doing the work yourself on a budget that's fair enough. The moment you pay a garage to do the work the material cost of the clutch is swamped by the labour cost and you would clearly change the whole assembly while the gearbox was out.

I think you can replace the seals with the wishbones dropped (as this allows you to pop the shafts out of the box and spill all the gearbox oil in your hair ). I have never done it though (at least I cannot remember doing it - maybe I have!).

Lightweight flywheel is going to make little difference - easier to stall, <0.1s acceleration improvement 0-60. It might make you a bit quicker up a hill as you've got less mass to lug up to the top

Cheers,
Robin

[Shug]

and not sure I fancy trying a gearbox change on axle stands.

I will be shortly, should be easier than the engine swap sans crane.

Not too bad IME - do some deadlifts to practise, though. I had an air ratchet, as nothing kills your arms like ratcheting away at all the bellhousing bolts lying on your back with your arms in the air. I had the assistance of my Dad, so I lay under the car and lifted, whilst he lay off to the side and maneuvered the box on and off. Not exactly simples, but not the job of nightmares that I'd feared.

[Corranga]

Not too bad IME - do some deadlifts to practise, though. I had an air ratchet, as nothing kills your arms like ratcheting away at all the bellhousing bolts lying on your back with your arms in the air. I had the assistance of my Dad, so I lay under the car and lifted, whilst he lay off to the side and maneuvered the box on and off. Not exactly simples, but not the job of nightmares that I'd feared.

I spoke to the mechanic I use last night who thinks my level of spanner monkeying should be advanced enough to manage it so I might give it a go. I'm thinking that I might take care of a few other bits on the car now, and postpone the box change to next winter, allowing me to save for some other bits, and then I can do the whole suspension strip down and POR15 at the same time.

I guess I really should be prioritising rad + PRT at any rate!

Thanks for all the advice everyone, I'll revisit this thread when I give it a go and get stuck with something

[woody]

I'm not dreading it too much tbh and can still remeber back to when I'd many many more bolts that were only spannerable to tighten, so not fearing it too much.

[Ferg]

Very interested in how you get on. I keep telling myself I'll do mine when the clutch goes. But judging by the comments I might have to wait too long for that.