Williamson by QUAD?
 

On Sep 6, 1:58 pm, "Dave Plowman (News)" wrote:
In article .com,
Bret Ludwig wrote:

Another substantial upgrade is the use of Oldsmobile valves in the RR
V8 engine.

Do you mean the Range Rover engine? That started out life as a Buick/Olds
unit.


No, the valve that fits the RR V8 is a big block Olds valve. You
order them from Manley (the engine valve Manley and not the
"thermionic valve" one) and the length is a little different-there's a
small up charge. Still a hell of a lot cheaper and a better part.

Williamson by QUAD?
 

If only Jaguar had used a better transmission, better rustproofing,
and better electrics. Actually what would have been even more useful
is had they offered the Gardner 4LK engine as an alternative as Mr.
Gardner tried to tell them.
The Jaguar engine is stout but heavy. With three Webers and an
American distributor or a Scintilla Vertex mag they are pretty
reliable.

Dunno where you get the idea Lucas distributors are not reliable.


Growing up in a family with several British cars.

Or
indeed the need to change from SU carbs.
he SU isn't that bad but needs constant maintenance. Later Jags had
the useless Strombergs which were terrible.

Six chokes worth of Webers will
increase the maximum power but loose the tractability. Three SUs are a
better bet for road use.

Williamson by QUAD?
 

In article om,
Bret Ludwig wrote:
Dunno where you get the idea Lucas distributors are not reliable.


Growing up in a family with several British cars.

I grew up with only British cars.;-) But the worst distributor I ever came
across was a Delco fitted to a Vauxhall.

Lucas ones of course required periodic lubrication - but if this was done
had a decent enough service life.

Or indeed the need to change from SU carbs.

he SU isn't that bad but needs constant maintenance.

Because they are adjustable and most carbs ain't plenty felt the need to
fiddle with them. Usually while not having clue as to how to set them
correctly. The only maintenance they needed was topping up the piston
damper at engine oil change times.

Later Jags had the useless Strombergs which were terrible.

Yes - they were slightly better at emissions control and semi tamper
proof. Compared to the SUs of the time - but SU developed a better unit
shortly afterwards.

Six chokes worth of Webers will increase the maximum power but loose
the tractability. Three SUs are a better bet for road use.

--
*What do little birdies see when they get knocked unconscious? *

Dave Plowman London SW
To e-mail, change noise into sound.

Williamson by QUAD?
 

On Fri, 07 Sep 2007 19:48:42 +0100, "Dave Plowman (News)"
wrote:

Later Jags had the useless Strombergs which were terrible.

Yes - they were slightly better at emissions control and semi tamper
proof. Compared to the SUs of the time - but SU developed a better unit
shortly afterwards.

The big problem with the Strombergs was that the piston was sealed by
a thin rubber diaphragm which would eventually split - usually at some
inopportune moment.

d

--
Pearce Consulting
http://www.pearce.uk.com

Williamson by QUAD?
 

In article ,
Don Pearce wrote:
Later Jags had the useless Strombergs which were terrible.

Yes - they were slightly better at emissions control and semi tamper
proof. Compared to the SUs of the time - but SU developed a better unit
shortly afterwards.

The big problem with the Strombergs was that the piston was sealed by
a thin rubber diaphragm which would eventually split - usually at some
inopportune moment.

Indeed - but that diaphragm meant there could be no leakage past the
piston while it was sound. However, the shorter travel of the piston
introduced other problems.

--
*Constipated People Don't Give A Crap*

Dave Plowman London SW
To e-mail, change noise into sound.

Williamson by QUAD?
 

Dunno where you get the idea Lucas distributors are not reliable.
Growing up in a family with several British cars.

I grew up with only British cars.;-) But the worst distributor I ever came
across was a Delco fitted to a Vauxhall.

Lucas ones of course required periodic lubrication - but if this was done
had a decent enough service life.

Oh, they'd last longer than you wanted them. The coils would fail,
the points would shift and lose time-Mallory did a land office
business in aftermarket ones for all BL products that took Ford parts
as I recall.

Or indeed the need to change from SU carbs.
he SU isn't that bad but needs constant maintenance.

Because they are adjustable and most carbs ain't plenty felt the need to
fiddle with them. Usually while not having clue as to how to set them
correctly. The only maintenance they needed was topping up the piston
damper at engine oil change times.


The SU is quite expensive over here, probably over there now too, and
they never really had any aftermarket support over here-right or
wrong, the trend was to get away from them. I suppose they aren't all
that bad. But Webers if correctly sized and set up are the best carb
anywhere for most anything. Eduaardo Weber SpA had the carb thing
down. The best US one was usually a Holley: I loathed and hated
Rochesters.

The Stromberg had a diaphragm and it would fail, but it was just
lousy aside from that.

Williamson by QUAD?
 

On Fri, 07 Sep 2007 22:37:46 +0100, "Dave Plowman (News)"
wrote:

In article ,
Don Pearce wrote:
Later Jags had the useless Strombergs which were terrible.

Yes - they were slightly better at emissions control and semi tamper
proof. Compared to the SUs of the time - but SU developed a better unit
shortly afterwards.

The big problem with the Strombergs was that the piston was sealed by
a thin rubber diaphragm which would eventually split - usually at some
inopportune moment.

Indeed - but that diaphragm meant there could be no leakage past the
piston while it was sound. However, the shorter travel of the piston
introduced other problems.

Leakage past the piston of an SU isn't a problem unless it changes.
You just calibrate the spring and needle to get the right mixture
curve, and choose the damping oil carefully. Too thin and it will
hiccup when you put your foot down, too thick and initial acceleration
is compromised.

It is, in my view an utterly brilliant piece of design, in which
everything seems to do about ten different jobs, unlike the Weber
where you have to change jets for every aspect of the power curve.

And as you say, the longer piston travel of the SU makes all of that
hugely easy compared to the Stromberg.

d

--
Pearce Consulting
http://www.pearce.uk.com

Williamson by QUAD?
 

In article . com,
Bret Ludwig wrote:
Lucas ones of course required periodic lubrication - but if this was
done had a decent enough service life.

Oh, they'd last longer than you wanted them. The coils would fail,
the points would shift and lose time-Mallory did a land office
business in aftermarket ones for all BL products that took Ford parts
as I recall.

All points 'shift'. If they didn't there'd be no adjustment provided.
As regards Mallory I recently fitted a Unilite to my Rover V-8 to replace
the high mileage DLM8 Lucas having been assured I'd notice a vast
improvement. And there was none. Of course if you have a modified engine
the ability to easily alter the advance curve would be useful. But mine is
standard.

Or indeed the need to change from SU carbs.
he SU isn't that bad but needs constant maintenance.

Because they are adjustable and most carbs ain't plenty felt the need
to fiddle with them. Usually while not having clue as to how to set
them correctly. The only maintenance they needed was topping up the
piston damper at engine oil change times.


The SU is quite expensive over here, probably over there now too,

As is the Mallory. I imported direct and got it for half the UK price.
Fact of life with some imports.

and they never really had any aftermarket support over here-right or
wrong, the trend was to get away from them.

All spares were and are readily available in the UK. Burlen Fuel Systems
now make them (and fuel pumps) and have good stocks even for older models.
Of course not cheap being no longer mass produced.


I suppose they aren't all
that bad. But Webers if correctly sized and set up are the best carb
anywhere for most anything. Eduaardo Weber SpA had the carb thing
down. The best US one was usually a Holley: I loathed and hated
Rochesters.

The snag with the DCOE Webers and similar designs is the poor atomisation
at low flow rates - ie low engine speeds. It can also be near impossible
to get smooth progression. The SU alters the venturie size to keep
relative airflow speed high to aid atomisation. The downside of this is
you can't make such a clear flow path at maximum power. But for road cars
it's a good compromise. Other ways of course are twin choke designs with a
small and large venturie - but these aren't known for long reliable
service life. Other thing with fixed jet carb is there is no compensation
for the inevitable wear - an SU unless bodged or neglected can be adjusted
as needed.

Of course BL cars used SU because they owned the company. Same as GM and
Delco or Ford and Mallory. But Rolls Royce continued with SU until they
changed to injection - and cost etc can't have been a factor.

The Stromberg had a diaphragm and it would fail, but it was just
lousy aside from that.

--
*The problem with the gene pool is that there is no lifeguard *

Dave Plowman London SW
To e-mail, change noise into sound.

Williamson by QUAD?
 

In article ,
Don Pearce wrote:
It is, in my view an utterly brilliant piece of design, in which
everything seems to do about ten different jobs, unlike the Weber
where you have to change jets for every aspect of the power curve.

The main problem with DCOE Webers is getting the progression from the idle
jets correct. Means enlarging holes in the body or drilling one in the
butterfly. Of course not a problem if only used for racing - but a real
PITA on a 'normal' car.

--
*I'm pretty sure that sex is better than logic, but I can't prove it.

Dave Plowman London SW
To e-mail, change noise into sound.

Williamson by QUAD?
 

On Sat, 08 Sep 2007 10:54:58 +0100, "Dave Plowman (News)"
wrote:

In article ,
Don Pearce wrote:
It is, in my view an utterly brilliant piece of design, in which
everything seems to do about ten different jobs, unlike the Weber
where you have to change jets for every aspect of the power curve.

The main problem with DCOE Webers is getting the progression from the idle
jets correct. Means enlarging holes in the body or drilling one in the
butterfly. Of course not a problem if only used for racing - but a real
PITA on a 'normal' car.

I used to have a pair of twin 45s on my mkI escort rally car (BDA
engine). I had it on a rolling road four or five times trying to get
that progression right. as you say, flat out was not a problem apart
from in long one-way bends when the levels in the emulsion tubes could
drop (or climb if going the other way) and the mixture wasn't right.

d

--
Pearce Consulting
http://www.pearce.uk.com