clutch balancing
Turbo Mini Forums

finaly got the car on the road,my spi verto clutch is not up to it so im after a upgrade, been looking at minispares turbo 20% uprated clutch, it says it will need balancing with flywheel,is this really needed?anyone not done this and had any problems?clutch was ok till i let my mate have a go in it,cheers phil

in a perfect world you need all the "rotating" assembly ballancing......... IT DOES MAKE A MASSIVE diffrence on how the engine runs so smoothley !!!!

its your mates right foot and boost that killed it ............ i doubt that the uprated clutch in the future would cope with anyones hunger for more power ?

So it's rts clutch or pre verto then, don't really want to go pre verto cos of thrusts wearing out , how quickly do the thrust washers wear with say a grey cover

Problem. With thrusts are . . . Clutch in and Mega rpm sat on the quarter mile line. . . That's where the problems come from usually not the road or track IMO.

The prevertro ultralight is much lighter than the vertro set up

how much poer/ boost you running? I reckon the minispares turbo 20% should be fine upto about 150hp

just running 7psi this year then going to up it when i upgrade pistons and gearbox,iv got a matty manifold with gt1752 so boosts up quite quick which wont help the clutch

Why doing the pistons why not have a fully balanced rotating assembly done? Gonna boost it do it right first time

Cos of money and happy to run low boost and iron out any problems this summer,would turn boost down some more but actuator is backed off as far as it will go to save this clutch

id be spending the cash to make a healthy core first rather than boost a compromised engine imo

i sacrificed a new modern turbo and other things for a better long block easy to change the turbo out later vs open the engine up to balance it or change pistons or what ever
better to spend cash to get the internals and long block right then get better turbo or nice bling stuff
if you know what im mean not having a go or trying to tell you what to do im just voicing my thoughts

Edited by Turbo This.. on 9th Feb, 2015.

I know what your saying and agree but I wouldn't have the car on the road till next year, I'm shure it will be ok on low boost this year, I'm nearly 40 so have abit more mechanical sympathy than a young lad, think I'm going to go pre verto with grey now.

Go for the standard turbo verto or, if in doubt, the 20% updated one that Joe mentions.

I'd rather either if those in mine over a grey.

In the 13's at last!.. Just

Which clutch you choose depends on max boost.
Whether you need to balance it depends on your max RPM.

(EDIT:As pointed out by stevieturbo below, boost isn't the same as torque. One effects the other, but an oversimplification on my half to keep in context of the original question)


My non balanced 1275 saw 5000 rpm daily. It had an unbalanced, uprated clutch, but I didn't know the clutch was also imbalanced due to one of the spring fingers snapping off and rattling around inside. I was aware of a slight vibration for thousands of miles, but nothing that I would take it apart for.



My last set of mods gave more power at higher revs, so I temporarily set the rev limit to 7000 and started tuning the last part of the map... It destroyed itself in 30 minutes.

The effect of any imbalance at 5k rpm is DOUBLED at 7k rpm. If you can tune your engine to make loads of torque low down the rev range and set a sensible rev limit, IMO, you shouldn't worry about balancing it just for a clutch swap (Just don't be tempted to lift the rev limit).

Edited by PhilR on 9th Feb, 2015.

Which clutch you choose depends on torque vs rpm.

Boost isnt the same.


And I'd be a bit concerned about buying any clutch where the seller is saying it has to be balanced. That would raise huge alarm bells about the quality of the parts they are selling.

All items like clutches and flywheels would be neutrally balanced as individual parts because they are changed often.

Yes there may be some longevity improvements by having these things and the entire rotating assembly balanced...but clearly that isnt always practical for all.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Minispares state that new Verto's need rebalancing with the flywheel!

http://www.minispares.com/product/Classic/...e/GCK151MS.aspx

If something is worth doing, it's worth doing half of.

And how many folk have ever re balanced the flywheel when changing the clutch on a Mini or Metro when there were thousands of them on the road in the 80's??
Ok nice to do but I certainly wouldn't lose much sleep about it personally. The clutches as fitted to 99% of modern cars are no different in principle to a verto and you never rebalance a modern clutch assembly before fitting it.

It was minispares that I had seen about balancing, minispeed are selling the same clutch but don't say anything about balancing ,PHIL R that makes sense to me and I won't be taking it much over 5000 anyway not with standard cam in it, after reading everyone's posts I'm going for turbo verto20%then il have two clutches to have a go at making an rts next time round

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

has anyone ever taken time to measure the ft pounds that different clutches will take like bolt the flywheel to the bench and make an old primary gear and cheep socket welded together to take a torque wrench drive? be interesting to see what combinations can be had or more so to preempt if a clutch it up to the job before balancing and all the jaz

Stevieturbo do you think il be ok to swap just the friction plate for a paddle disc? It only just slips as is, I'm not going to be doing a lot of mileage either

Imo why the engines in bits get it balanced it's not that expensive then you have peace of mind it's done.

I properly don't need it on My 998 but it's getting itit. Difference in driving I found was very different on a friends one it idles better and revs up more freely. The lads on here have tired everything and made the mistakes learn from them. They've taught Me alot since joining.

That would work in a fashion for a static load test, the tricky bit would be to test dynamic load like when slipping/re-engaging the clutch after a gear change. I also guess heat becomes a factor here too.

If something is worth doing, it's worth doing half of.

I found the strongest clutch for mine through a simple test....but I did have access to multiple clutches to do so.

Set cover on the floor, place the cup over the fingers and stand on it.

Some would depress the fingers with ease, some actually took a good push to depress them. These were by far the strongest clutches.
Even for clutches in the same packaging, intended for same fitment...the vast difference in diaphragm strength was shocking.

This test wont give you any units of measurement as far as torque ability goes....but it's a fast and easy test if you have a few covers sitting about.

It was easy for me as mini/metro clutches would have been more popular back then and the local factors always had several in stock I could check out before considering trying them. Plus I had a good few OEM and turbo clutches from cars I took apart.

I used the same cover for many many miles, easily over 100k.
That said, I did have the friction surface replaced at least twice and also flywheels as the paddle discs did eat into them with normal daily use.
But the main flat steel bit and diaphragm spring remained the same.
It wouldnt last forever though, as where the cup presses on the fingers was wearing

As John says, getting a real test figure would be impossible...but getting a simple clamp/diaphragm clamp strength should be easier.
Testing the fingers as I describe is almost the same....end of the day if it's harder for you to depress the fingers, you can be 99% sure it will also clamp harder.

@ Phil, if the organic plate was hanging on well then yes I'd have good confidence a paddle disc would make a huge difference. Certainly isnt expensive to try it.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

This balncingv thing is very subjective. The verto clutch was a complete balanced unit, flywheel included which is why(as well as a financial gain point of view) Rover only sold complete balnced assemblies more so towards the end.what that meant was the whole assembly was a single balanced unit rather than indivudual balanced parts. This is the current situation. I have found huge variation in balance of just the verto pressure plates. Add that to a flywheel balanced as a single unit from another clutch and it either gets bettet or Worse

it us generally assumed that it is going to be balanced as an assembly so the individual parts are supplied un balanced.

100% balance them as an assembly. AP themselves do not recommend fitting or trying to balance the clutch by itself.

I have never seen any aftermarket Verto clutch of any make been sold with a flywheel.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will