16 replies to this topic

[Merryck]

I was reading an article about the 'Milwaukee Midget', an MG Midget that was built a few years ago to set the speed record at the Bonneville speed flats for sub 1 litre classics.

http://www.landracin...pic,4087.0.html

There's plenty of reading there for you - only 83 pages!!

Basically the guy decides the engine he wants to go with is a 970cc Cooper S engine. He builds the engine himself, and it made me want to find out a bit more information about them. From what I can gather, the only differences between the 970 and the 1275 engines are the crank, push rods and the cam shaft. Is this correct? I haven't been able to find anything for sale anywhere.

Does anyone know if you can buy the parts to build a 970 engine yourself? It would be amazing to be able to put one in the car, 10000 rpm would be awesome.

[mab01uk]

The parts needed to build a genuine 970 S engine are rare and expensive as less than a 1000 were ever made in production for selling as road cars, purely to qualify the S for the 1000cc class in saloon car racing, however anything can be built if you have the desire and the cash to back it with.......

Edited by mab01uk, 26 May 2012 - 07:12 PM.

[Cooperman]

I have built a couple of 970 engines over the years, the last one being for my son's historic rally car to enable it to win the 'up to 1 litre' class.
It had a 286 cam, flowed head with 35.6 mm inlet & 30.5 mm exhaust valves, 11:1 compression ratio, twin HS4 carbs, light steel flywheel, fully balanced bottom end, large alternator and water pump pulleys, duplex timing gears, comp. clutch and the usual LCB manifold and Maniflow rally exhaust system. Distributor was an Aldon custom made unit.
It had 85 bhp at 7000 rpm, but really nothing below about 4000 rpm. It needed a straight-cut close ratio gearbox to keep it 'on the cam' and a 4.1:1 final drive giving 13 mph/1000 rpm in top, 7000 rpm being about 90 mph.
It was a potential class winner, although a good 998 Imp with full-race engine was a bit quicker on a test. I only drove it on one rally and didn't like it when compared to my 1275 'S' as it just seemed like all revs and no real 'go'.
It's an interesting engine though, but I wouldn't want one in a road car.

[mk1leg]

I Know of a full race prepared 970S complete engine and box...............I'm just waiting for when the chap decides to part with it...............and I will make him an offer................

[Merryck]

I just might have access to a CNC machine (and operator) so I might have to put this on the list of projects to get done!

If I do I'll make sure I let everyone know - the more the merrier!

[ericp]

Hello!

 

We have a 970 engine for sale in the states if anyone is interested.  We will ship.  I'm posting for my father so please email him directly:

 

https://www.minimani...rks_Mini_Cooper

 

[Spider]

The differences between a 1275 engine and a 970 are a few more than listed.

 

Crank (as mentioned)

Con Rods.

Camsahft was the same as per MKI 1275 Cooper S, which is in fact the same profile as fitted in the 1098 and standard 1275 engines.

Pushrods (as mentioned) though you can usually use small bore types

Block - though most 1275 blocks can be modified. 3/8" needs to come off the deck

 

There's a group in NZ who used a 970 engine - as a basis - for setting a Record at Bonnyville in recent years. it was bore out 0.020" which made it 999 cc, to bring them in to the under 1 ltr class

[Cooperman]

The 970 really was only really good for competition in the up to 1 litre class.

I recall driving a standard road 970 when they were new in 1965 and at that time I had a 998 Cooper with a flowed head, a 997 cam and increased CR. My 998 was certainly much nicer to drive although the 970 had better brakes.

[r3k1355]

So for the speed record does the car have to retain the original engine/engine type??

 

Because it just seems an odd choice for something like land speed, surely you'd dump a motorbike engine in, or a more modern turbo lump?

[Spider]

Look up the rules.

[jt19]

The bonyville mini also had a 16valve head and turbo if I remember correctly

[Spider]

The bonyville mini also had a 16valve head and turbo if I remember correctly

 

Certainly did

 

Here's a great little video on it 

 

[r3k1355]

Look up the rules.

 

Kind of why I asked, so I didn't have to trawl through the rulebook to answer a simple question.

[mini13]

Depends category to category,

For the Bonnoville thing there is probably an original engine class, and one for free engines.

[Spider]

 

Look up the rules.

 

Kind of why I asked, so I didn't have to trawl through the rulebook to answer a simple question.

 

 

There's so many classes and sub-classes within classes it's not a question that's easily answered on the forum.

 

After a cursory read through them you may get a feel for what class you could consider and build to that. Some classes you do need to retain the complete engine and components, though some can be modified from stock parts, right through to complete engine swaps.