The load on the clutch is not only a factor of horsepower.
The weight of the vehicle has a large effect on clutch life.
We used a small Ford zephyr clutch behind a high performance 283 Chev in a
Mk 3 Zephyr driving through the original Ford four speed gearbox. This set
up worked ok in the lightweight Zephyr but the same clutch and gearbox would
not have survived if installed behind the same engine in a full size Chev.
The Alpine is a small lightweight vehicle so I would expect clutch life to
be sufficient to last untill the engine needed attention.
I drove a 3.4 Jaguar with manual box and quickly learned that slipping the
clutch was a big "NO NO". The magic smoke escaped as quickly as foward
propulsion ceased :-). Jag drivers manual says " for best acceleration off
the line use about 2000rpm, allow cluch to fully engage before flooring it"
Slipping the clutch on normal changes is clutch abuse and does not improve
performance.
In fact driving the Jag taught me to allow all the bits of clutch/gearbox
etc to work at their own pace. Fast gear changes never happened with the Jag
(Moss) gearbox. A pause in neutral between gears always helped. The same
technique in my 55 Californian means silent gearchanges occur, and gearbox
bits don't fall in the bottom of the box :-))
Australian car racing involves great races like Bathurst where "hard"
drivers go quickly but often never finish because they break something.
Rootes Australia entered the Humble Minx (badged as Sunbeam ) in the great
race. It finished and put up lap times that I feel were nothing short of
amazing considering that this was a stock unmodified sedan.
I personally have learned the hard way about vehicle abuse. If it is broken
I get to walk :-) so coaxing maximum performance without breaking anything
has become second nature to me.
The point that these Volvo parts are more readily available is a good one
and adaptation of these parts should not be difficult, but to say that the
substitution is needed because the original parts cannot take the power is
not suffucient reason for me to make this change. In Australia I would
simply adapt Holdem ( GM) parts as they are cheaply available where Volvo
parts cost a premium in Australia.
If the Rootes engine drivetrain is not holding together then it was not
assembled correctly. I have rebuilt motors in my previous Hillmans and
pushed them full throttle for up to 100miles without failures. We are
talking about sitting on 6 -7000rpm for 20 miles at a stretch. To the extent
the exhaust piping becomes more than red hot.
I have gone on a bit here but the point I am trying to make is that the
Standard Alpine drive train is more than capable of handling any amount of
enthusiastic street use and a fair amount of classic racing use as well.
Keith
55 Californian
56 Minx
68 Hunter
>---- Original Message -----
From: <ellis838@concentric.net>
To: <alpines@autox.team.net>
Sent: Monday, January 27, 2003 2:28 AM
Subject: Re: VOLVO Clutch
> The MGB cover and Volvo plate works well is cheaper and easier to get,
> I also think the quality of the MG/Volvo parts is better. Sorting the
> combination of pivot block and release arm is the only difficult part.
> The 7 inch Rootes plate seems to like to spit the springs out and the
> plates I have bought look like they were rebuilt in the back yard in
> grandpas spare time. I figure my 1725 is good for 130+hp and with the
> 205 tires I am not sure the stock 7 inch clutch could take the strain...
> Jim E
>
> Alkon wrote:
>
> >The Volvo clutch throwout bearing is a ball race and runs on a guide tube
> >around the gearbox input shaft. This type of clutch is totally
incompatable
> >with the Rootes carbon throwout bearing. If you want to use the Volvo
clutch
> >pressure plate then a guide tube and the correct type of throwout bearing
> >must be used. This work is really fairly simple to do and made easier if
you
> >can steal the right parts off a Volvo. I have done this adaptation to
couple
> >a Jag box to a Chrysler Hemi V8.
> >
> >Unless you use dragracer clutch techniques. (7000rpm and step off the
> >clutch.) then the Rootes supplied item will handle anything that your
1600
> >or 1725 engine can deliver.
> >
> >Keith
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