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mini63 wrote:A couple more pictures.
Claude Ballot-Lena and Jean-Louis Marnat entry, 1966

The car looks different though in each picture but the entry list details only one for that year.

I wonder what the speed difference was between the marcos and that 275 GTB!

I bet it was some experience when that came howling past in the dead of night!

mini63 wrote:A couple more pictures.
Claude Ballot-Lena and Jean-Louis Marnat entry, 1966

The car looks different though in each picture but the entry list details only one for that year.

The second picture is from 1967. It is the car of Chris Lawrence and Jem Marsh. They only lasted 13 laps when the oil pump gave up!

rich@minispares.com wrote:

Jeroen Booij wrote:
Thanks for that Richy.
I have just spoken to a friend who knows about these sort of things, and I told him that a new world is opening up for me. I have always totally lost myself in the historical part of motoring things, not so much in the technical side. But for now I have to take a plunge in there, too. I must say it's very refreshing!

j

ive just worked this out

on a 165 tyre a 2.49 gives 22.75 mph on a set of 1:1 drops

that's

6000 rpm = 136 mph

6500 rpm = 147 mph

7000 rpm = 159 mph

Well… I know it reached 141 mph and revved up to 8,000rpm…

A 2.9 : 1 final drive would give about 140 odd at just a whisker over 7,500 rpm

Jeroen Booij wrote:


Well… I know it reached 141 mph and revved up to 8,000rpm…

a 3.4:1 running 0.95:1 straight cut drops would give 138 mph at 8000 rpm

a 3.1:1 running 1:1 drops would give 146 mph at 8000 rpm

the 3.4:1 was certainly available in period, where as a 3.1:1 is a late 1980's one.

the above is worked using the rolling radius of a 165/70 tyre, so I suppose a slightly taller racing tyre would let a 3.4:1 do 141 mph

In view of the fact the engine lasted the race & was supposedly a "rally-ish" spec, I reckon it is unlikely that they would have been pulling max revs down the mulsanne straight.

Add to that the "legend" that it has a 2.4:1 CW&P, I reckon a 2.9 special could have been a possibility.

This is of course, just a guess.

Unipowers were using 2.9 in 1966. I've an interesting article I'll post up describing my car doing 130mph with Andtew Hedges at the wheel in December 66.

Pete wrote:Unipowers were using 2.9 in 1966. I've an interesting article I'll post up describing my car doing 130mph with Andtew Hedges at the wheel in December 66.

pete


where they a straight cut jkd one?

mk1 wrote:In view of the fact the engine lasted the race & was supposedly a "rally-ish" spec, I reckon it is unlikely that they would have been pulling max revs down the mulsanne straight.

Add to that the "legend" that it has a 2.4:1 CW&P, I reckon a 2.9 special could have been a possibility.

This is of course, just a guess.

There is a quote in Hrubon's autobiography about the revs it made, I'll have to check that. Mind you: it was the Cooper 'S' engine tuned by Hrubon that was used at Le Mans, not the ST one.
Oh - and thanks for the calculations Rich. It all does make sense.

Will you be restoring it with the correct ratio Jeroen? if so, it may limit it's use somewhat?

Al

Jeroen Booij wrote:
There is a quote in Hrubon's autobiography about the revs it made, I'll have to check that. Mind you: it was the Cooper 'S' engine tuned by Hrubon that was used at Le Mans, not the ST one.
Oh - and thanks for the calculations Rich. It all does make sense.

j

one thing to consider is this

if it was a 2.9 that was used, someone may have miss read the hand written notes and thought the '9' was a '4'

the reason I say this is that one of my French customers has a really strange was or writing the number 9 that makes it look more like a sort of 'y' shape that makes it look like a '4' - it may be that French children where taught to right numerals in this way at school in the 1960's?


next time I see one on his order I will take a photo for you!

That's the point I was trying to make earlier a hand written 9 & 4 can be easily confused.

rich@minispares.com wrote:

Jeroen Booij wrote:
There is a quote in Hrubon's autobiography about the revs it made, I'll have to check that. Mind you: it was the Cooper 'S' engine tuned by Hrubon that was used at Le Mans, not the ST one.
Oh - and thanks for the calculations Rich. It all does make sense.

j

one thing to consider is this

if it was a 2.9 that was used, someone may have miss read the hand written notes and thought the '9' was a '4'

the reason I say this is that one of my French customers has a really strange was or writing the number 9 that makes it look more like a sort of 'y' shape that makes it look like a '4' - it may be that French children where taught to right numerals in this way at school in the 1960's?


next time I see one on his order I will take a photo for you!

Good point, could well have been the case. I don't know. 2.9 definitely makes sense to me now.
Oh, and, Al, I think that's a diff ratio one can live with quite easily. Am I right Rich?

Just made a little update on my weblog with some photographs of the surviving fuel tank and the pick-up points for the roll bar.
Have a look if you like here: http://maximummini.blogspot.com/2016/12 ... cos-3.html

Jeroen Booij wrote:

rich@minispares.com wrote:

Jeroen Booij wrote:
Well… I know it reached 141 mph and revved up to 8,000rpm…

I think the '66 Mini Marcos was clocked at 146mph down the Mulsanne Straight?

Jeroen Booij wrote:


Good point, could well have been the case. I don't know. 2.9 definitely makes sense to me now.
Oh, and, Al, I think that's a diff ratio one can live with quite easily. Am I right Rich?

All depends what you are going to do with it Jeroen. On a road car a 2.9 will make a great motorway muncher but if you combine it with a lumpy cam you could have a car that is very sluggish to get away from standing and a bit of a cow in traffic! Sometimes compromises to the original race spec are needed when you are restoring a car like this, unless it's going to be racer again?!

Many years ago I remember having a conversation with someone at Longmans about the Mini and the Metro (you can tell how long ago I'm talking about!). He said to me that whatever they did to the Mini they couldn't get it to do any more than about 108mph out of it. He went on to say that at the time they were getting 120mph out of the Metro.

Graham

GrahamWRobinson wrote:Many years ago I remember having a conversation with someone at Longmans about the Mini and the Metro (you can tell how long ago I'm talking about!). He said to me that whatever they did to the Mini they couldn't get it to do any more than about 108mph out of it. He went on to say that at the time they were getting 120mph out of the Metro.

Graham

Yep, hence the Minisprint!

Pete wrote: Back to the Marcos (that 2nd pic is the '67 one Michael) are there any interior shots Jeroen? Usually the hard one to find!

Thanks Pete for clarification.

As Pete has already suggested what you finally decide to use FD wise should be determined by what you are planning on using the car for NOW, not what it had then. If you are building it totally back to 1960's spec then fine, use the original 2.9, but if you plan on driving it on the road be prepared to COMPROMISE!

Things like actual engine spec & FD are important to know as part of the overall story, but they could make the car pretty much undriveable on anything but a race track. A little bit of compromise could leave you with a truly great historic car that is a joy to drive anywhere & can be easily converted back to full historic race trim by swapping the engine.