15 replies to this topic

[Spider]

I saw this advertised today



Apparently the head (and block ?) are one of the many OHC A Series that were experimented with. There's no suggestion in the advert that the Mini Moke left the factory with the engine rather, it was fitted later.

It does sorta look A Series-ish. Anyone here be able to shed some light ?

 

[sonscar]

Machine a cam carrier to replace the existing train and a drive pulley,might look exactly like that.Doesn't look like recent work,Steve..

[mini13]

Well thats certainly an interesting peice,

 

Initially I was thinking it could be a modded std head, but the bit next to the heater take off is different, also is that a filter on the block ala south african 1100?

[mab01uk]

Interesting photo to compare with those below....as said above by 'mini13' the oil filter in the Moke photo does appear to be on the block like the South African A-series engine.

BL's OHC A-Series engine for the Mini in 1975 which featured belt drive to the overhead camshaft, single or twin-SU carbrettors and retained all the familiar A-Series features, such as the starter motor, alternator, distributor and spark plugs on the same forward facing side of the original cylinder block. There were also inline versions developed for BL's rear wheel drive cars. 11 prototypes of all sizes were built and completed 3,200 hours on test beds and 2,200 vehicle miles. The 1275cc OHC A-Series produced 84bhp @ 6750, torque 80lb/ft @ 4,500 (against 59bhp @ 5300, torque 69lb/ft @ 3000 for the pushrod engine) in standard form. There were also 970cc and 1097cc versions produced and tested but the project was eventually canceled due to the mounting losses of British Leyland which had become nationalised during the engines development.
More details here:-
https://www.theminif...ines/?p=2431295

 

Edited by mab01uk, 01 July 2022 - 08:44 AM.

[stuart bowes]

what would the benefit be of OHC instead of the push rods?  easier tuning, or power gains, or what 

 

weighed up against the increased likelyhood of timing going out because of a belt snap (less likely with chain?)

 

another plus is easier(/possible) to change the cam with engine in-situ though I guess

 

interested to know more 

Edited by stuart bowes, 01 July 2022 - 09:14 AM.

[mini13]

Well, to be honest it dosen't offer huge benifits unless you design the head to suit (ie breathe better, non siamese ports etc)

 

However, OHC would allow you to get the valves open quicker, a lot of performance cams do this but theres a limit to how far you can go reliably, certanly the diameter of the cam follower limits this, and there have been been cams avalable that require the followers to be replaced with larger diameter ones to allow the acceleration ramps to work.
Also anything you can do to stiffen up the valve train is considered good, as you can run lower poundage springs, again more reliable, less wear, less losses etc.

 

 

 

what would the benefit be of OHC instead of the push rods?  easier tuning, or power gains, or what 

 

weighed up against the increased likelyhood of timing going out because of a belt snap (less likely with chain?)

 

another plus is easier(/possible) to change the cam with engine in-situ though I guess

 

interested to know more 

 

[Ethel]

Had to check the date, several times.

 

The cam must be centred on the pulley and there must be valve springs under that  almost standard looking cover. I can't imagine how both can be true.

[nicklouse]

Had to check the date, several times.

 

The cam must be centred on the pulley and there must be valve springs under that  almost standard looking cover. I can't imagine how both can be true.

Bcut the head is nothing like standard. It hangs over the transfercase more. Look at the recess between the left front stud and the water take off. There is something very odd going on but I don’t know.

[Ethel]

Yes, I'd love a look under the cover...

 

It'd need to be a bit longer to house the bearings, but it isn't any taller. 

[nicklouse]

I saw this advertised today



Apparently the head (and block ?) are one of the many OHC A Series that were experimented with. There's no suggestion in the advert that the Mini Moke left the factory with the engine rather, it was fitted later.

It does sorta look A Series-ish. Anyone here be able to shed some light ?

Chris, where was it for sale. Down there or up here?

 

plate does match a UK reg but I don’t believe it is.

 

Datsun?

[DeadSquare]

I saw this advertised today



Apparently the head (and block ?) are one of the many OHC A Series that were experimented with. There's no suggestion in the advert that the Mini Moke left the factory with the engine rather, it was fitted later.

It does sorta look A Series-ish. Anyone here be able to shed some light ?

 

I wonder how many people have to crouch under the bonnet, tightening down the cam-cover ?

[DeadSquare]

@ Nicklouse.

Chris, where was it for sale. Down there or up here?

 

plate does match a UK reg but I don’t believe it is.

 

Datsun?

In over 25 years of looking, I have never come across a photo of a Datsun engine, but I think that I may have seen something like this, in Graham Cooper's scrap yard in Wolverhampton.

The thermostat housing would have been hung out in front of the head like this, but had been treated to the usual BMC "lump-hammer", otherwise it was a 5 port head with two rows of bent rocker pedestal studs.

[nicklouse]

@ Nicklouse.

Chris, where was it for sale. Down there or up here?

 

plate does match a UK reg but I don’t believe it is.

 

Datsun?

In over 25 years of looking, I have never come across a photo of a Datsun engine, but I think that I may have seen something like this, in Graham Cooper's scrap yard in Wolverhampton.

The thermostat housing would have been hung out in front of the head like this, but had been treated to the usual BMC "lump-hammer", otherwise it was a 5 port head with two rows of bent rocker pedestal studs.

Wolverhampton is the area it is up for sale in. Just found the advert. Owned since 1973. 

[DeadSquare]

 

@ Nicklouse.

Chris, where was it for sale. Down there or up here?

 

plate does match a UK reg but I don’t believe it is.

 

Datsun?

In over 25 years of looking, I have never come across a photo of a Datsun engine, but I think that I may have seen something like this, in Graham Cooper's scrap yard in Wolverhampton.

The thermostat housing would have been hung out in front of the head like this, but had been treated to the usual BMC "lump-hammer", otherwise it was a 5 port head with two rows of bent rocker pedestal studs.

Wolverhampton is the area it is up for sale in. Just found the advert. Owned since 1973. 

 

That's interesting,.  Can we go and view it ?

[mab01uk]

1965 Mini Moke for sale, owned since 1973 but it now has a prototype "A" series OHC chain driven engine.

https://en-gb.facebo...28545390518912/

Edited by mab01uk, 01 July 2022 - 10:18 PM.