7 replies to this topic

[crizd]

91 Cooper Carb

Why oh why does the MG engine produce more than 10horses more than the cooper lump?

Its to my understanding that the heads/valves/cam is exactly the same, only the diff is different.

But surely 10+ hp isnt lost in the diff......

Ive got one of those machanic bibles with all the information about every car ever.com and both Mini Cooper carb and MG Metro have exactly the same coils, dristributors, advance timings.

If anyone knows why this "mg metro" engine is so basic in comparison I would be much happy to know.
its been bugging me for ages!

[Kerrin]

I thought the cam on a MG metro engine was higher spec than a cooper carb, they are slightly lumpy, whereas a cooper carb seems smoother.

[crizd]

Interesting. Does anybody know what cam profile is in them both?

[Ethel]

Depends what year of Metro but: higher compression, better manifolds, bigger inlet valve & the cam. Also the old MG spec was based on higher grade, leaded, fuel.

[crizd]

Oh my.

Ive read a broucher that states the Cooper Carb engine is just an MG metro ontop on the standard mini box. Sounds like its just a mini engine, with a Hif44.

[Ethel]

So were the later MG Metty engines, thanks to unleaded. I've got a Metty Haynes, I'll see if I can find the specs for you.

Old spec,

Compression 10.5:1
Inlet valve 1.4"
Cam in 252 degs, ex 268 0.250" lift

I think the unleaded engine just has a standard head and pistons.

[jaydee]

Oh my.

Ive read a broucher that states the Cooper Carb engine is just an MG metro ontop on the standard mini box. Sounds like its just a mini engine, with a Hif44.

The brochure was probably referring to the RSP Cooper, which had an MG metro unleaded engine with MG metro turbo gearbox.

[dannoodle]

"The engine of the RSP Mini Cooper was a detuned MG Metro engine. In 1989 the A-series engine had been converted to run on unleaded petrol, and all the 1275cc engines now used the same sized inlet valves, which in the MG Metro probably cost around 4-5 bhp. When this engine was fitted to the Mini it used a catalytic converter. Whereas the factory quoted the 1982 MG Metro as having 72bhp, the Mini Cooper RSP now only had 61bhp, but it was still good for 90mph. The RSP Cooper was a limited edition and soon sold out. Of course one could be cynical and suggest that perhaps it started as a marketing exercise to offload 1650 surplus MG Metro engines now that the Metro was powered by the K-series engine. But from September 1990 the Mini Cooper became a mainstream production car and soon around a third of all Minis were Coopers. Who was buying them? The standard Mini had been aimed at female drivers; perhaps the Cooper was bought by men who would otherwise have bought motorcycles to relive their youth?

For those who thought the standard Rover Mini Cooper with its 61bhp a little gutless, help was at hand. In March 1991, with Rover's approval, John Cooper Garages began selling the first of several Janspeed "S" packs: tuning kits to turn one's Mini into something more potent. At first any Rover dealership could fit the kits, but later this task would be entrusted solely to JCG in Ferring (and later at their new Mini-only facility at East Preston). The first JCG "S" pack boosted power to 78bhp and when tested by AUTOCAR AND MOTOR magazine in May 1991 it acheived uncannily similar results to the 1275S AUTOCAR had tested back in 1964."