8 replies to this topic

[MJWarren]

Heres the link to someting that interested me, no good really without the cooper s rods if im right in thinking? as the journal sizes are different?

Might be good for someone though?

http://www.ebay.co.u...=item35b76d3c52

[Cooperman]

At Std/0.010" it's an excellent crank. You would need 'S' rods as the big end journals are 1.625" dia instead of 1.75".
You can't just drop the crank and rods intoi a non-'S' block as the main bearing widths are different and some different thrust bearings are needed.
With a fully balanced EN40B 'S' crank you can safely rev the nuts off of it so long as you also have a centre main bearing srap on a non-'S' block.
I reckon that crank is worth around £400 maybe a bit more.

[The Otter]

A friend of my uncle's once told me that he used to own a highly modified 1380 monster of a mini that he used for rallying back in the late 70's, and I remember him telling me that he had one of these cranks in his engine, and it could rev to around 11,500rpm! I was very dubious of this claim when he told me, especially knowing the sort of person he is, but I have always wondered whether he was talking complete and utter nonsense or whether it is actually feasible?

He told me he had to rebuild the engine every 1000 miles, something about using softer bearings so they would effectively disintegrate and keep the crank in perfect condition or something like that. I don't know much about engines mind you, so if that's wrong I'm sure you can sort of work out what I mean!

I hope you can sprinkle me with some of your knowledge Cooperman, this has been on my mind for a while

[Cooperman]

There would be no benefit by revving to 11500 rpm even if the engine would take it, especially on a rally car, as a good rally cam, such as the 544 or even 649 back in the 60's/70's would run out of power at a max of 7200 rpm.
I've heard of the ultra short-stroke 970 'S' revving to almost 1000 rpm with a very special race cam and my son and I used to rev our 970 with a 286 to around 7800 rpm, but not a 1275/1330/1380.
I've never heard of 'soft' bearings and have always used Vandervell and they have been fine with the EN40B nitrided 'S' crank.
The idea of a 1380 for rallying would be to run a slightly less aggressive cam and use the better torque to give the best performance on events. I'm not a great fan of the 1380, preferring a 1330 as that can give as much as the 1380 and with thicker cylinder walls.

[Artful Dodger]

11000?? blimey he must have been giving it some!


watching this crank, could be of some use to me

[minisam92]

shame ive got no income thats only 10 miles away from me

[oltonlad]

£154....with 6 mins to go.........thats cheap........its gotta go for more than that surely!

[mini-luke]

£307, cooperman wasn't far off.

[oltonlad]

£307, cooperman wasn't far off.

yeah............not far off.............but then cooperman does know his stuff......especially when it comes to coopers........i wish that i still had my "s" engine, i sold it for £400 about 10 years ago.......what a plonker!!, it was pushing 98bhp on twin HS4's (it wasnt standard).......i really really regret selling that engine......