Heavy Duty Clutch

[Graeme Naisbitt]

I know there was a discussion about slipping clutch's a couple of months
ago. Mine is going but I want to replace with a heavy duty clutch as I have
plans for a turbo/supercharger or NOS kit in the near future. Can anyone
recommend a supplier/installation in Auckland area? Browns Bay area would
be ideal. Alternatively I could fit myself as I have fitted quite a few in
the past, but I'm an ex-pat with few tools yet so it may turn out to be
cheaper to have it fitted instead of buying trolley jack, axle stands
etc...

Thanks in anticipation

Gram

[Ray]

Graeme
Rotary Power in Glenfield supplied and fitted my "centre force" clutch i think he
did Lou's as well, (who is on this list), on both our super charged cars, pedal is
very light, also consider fitting a lightened flywheel if funds permit, while you
have the gearbox out.
Ray


[...]

[Clive Granger]

Ray,
Do you have any problems driving in stop/go traffic with the centre force
clutch? Racing clutches are not so good on the road I hear, where to be
able to slip the clutch a bit makes for easier driving. Also carbon/kevlar
clutches can wear the flywheel down quicker I have been told. Is this true?

I have a 'standard' heavy duty clutch in mine and the pedal action is also
just as light as the stock clutch.
Clive.

[Ray]

Clive
I have no problem at all in traffic, in fact the clutch is lighter than stock, i
know of at least 6 people with Turbo/supercharged MX5's in Auckland ranging from
160BHP-260BHP running the centre force and they all say how light and smooth the
clutch is, the centre force clutch has weights on it that put out more pressure as
the revs rise, hence putting more pressure onto the driven plate, but it aint cheap,
cant remember how much it was now, i know it made my eyes water, but then good quality
gear is'nt cheap, the last thing you want to do is to keep taking the gearbox out,
do it once and do it right is my motto.
no clutch will wear out a flywheel its the constant slipping of the clutch for fast
take offs that destroy a flywheel, and of course the clutch, and a worn slipping
clutch will also damage the flywheel whether its riveted or bonded, thats one of
the reasons why i recommend putting in a lightened flywheel as a lot of stock flywheels
are so damaged they need refacing, so you might as well put in a lightened one.
Perhaps you could mention your make and cost for interested people Clive.
Ray

[...]

[Gary Morrison]

Ray,

What was the lightened flywheel you used, and how light is it?

Gary

[Ray]

Gary
All lightened flywheels are steel or forged aluminium, my steel one weighs 12lb,

the rule of thumb is you need 30% reduction to notice and gain any difference, 1600's

are around 18lb-19lb i think and the 1800's a bit heavier and all are cast iron,

if you go lighter (and i'm looking at an ali one of 6lb, $1000) it will play havoc

with the idle, because there is no mass to keep the engine spinning when you shut

the throttle say coming up to traffic lights, i'm not a believer in shaving some

off the stock one as i have seen what happens if too much is taken off cast iron

flywheels, they can explode and i've seen the mess it makes when they come through

the car by your feet at 7000rpm, if it doesn't take your ankles off, now i know

there's

a few members who have taken a couple of pounds off a stock flywheel usually the

ridge, this is there for a reason, "STRESS", and i defy anybody to tell me they

notice

the difference with that small amount removed, i personally consider it a waste

of

time in removing the gearbox for 2lb and the risk that goes with it, this just my

opinion of course, its always one of the first thing i do when looking for more

performance,
[...]