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convert cooper engien for spridget?

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Aggudabbu

Aggudabbu

Senior Member
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Hey guys I'm new here so go easy on me okay!

I've been working on my ASH mk1 with a speedwell monza bonnet for the last year and has completed all the body work, breaks etc. The car stood in a garage for 38 years before I bought it and when I fired it up it turned out that the poor 948 engine was rubbish and beyond rescue. So now I was thinking that I would like to put in a 1275cc engine instead.

But it turns out, that where I live in Sweden a 1275cc engine to fit in my sprite isn't to easy to come by, so I was thinking is it possible to "convert" a horizontal cooper engine to fit in a spridget? (since I already have a cooper 1275cc GT engine just laying around)

I suppose what I would need is another endplate, crank and clutch and then maybe move/fabricate some new brackets in the engine-room

Or am I at fault in thinking so?
Have anyone here heard if this has been done, and if it's possible are there any pros and cons?

I appreciate all the help and input I can get

Best Regards// Alex
 
I would try and sell and or trade for a correct 1275 I think there is quite a bit of work and ancillary parts to do what your proposing. Manifolds, exhaust,
bottom end pan flywheel could get spendy
 
send a message to spritenut. I believe that he has done exactly what you are asking.
 
If you have a 1275 Cooper-S engine, sell it and use the proceeds to buy the Spridget engine. Not all Mini 1275's are Cooper-S engines.
 
Re: convert cooper engine for spridget?

Pythias said:
send a message to spritenut. I believe that he has done exactly what you are asking.
Click to expand...

alright thnx i'll try and do that!

and you other two, I would love to just buy myself the right engine to rebuild but the thing still is that there is none to buy! Been looking all over for an engine or a car with it that I can use as a donor for parts but with no luck
 
Re: convert cooper engine for spridget?

As I recall there is something different about the crank. At one time I had several 1000cc minis(not coopers)when I lived in England. I tell you one thing, that intake with the single carb might not been a powerful as the twin carb but they never gave any trouble, they just worked. Hap might be the one to ask but I'm pretty sure there is a show stopper that won't let the Austin Mini a series fit into the sprite or Midget.
 
Re: convert cooper engine for spridget?

Crank is different, so is flywheel.
 
Re: convert cooper engine for spridget?

If you have a 1275 Gt, and it's to the same spec as UK 1275GTs, you have a better base for a high-output 1275 than a Cooper 'S'.
You'll need new internals, but if you're building from scratch, the block and head are where to begin.
 
Re: convert cooper engine for spridget?

I converted a Sprite 1275 to a Mini side winder.
This was simple, just a little work to the rear main cap but I already had the Mini crank and related parts.
Going from a Mini to a Sprite is a lot harder. I am not sure what all has to be done but it was not worth the trouble from what I heard.
 
Re: convert cooper engine for spridget?

Somewhere (not too long ago) Hap made a post with the details.
 
Re: convert cooper engine for spridget?

On the other hand, someone here could likely figure a cheap way to ship a block from here or England
 
Re: convert cooper engine for spridget?

You need the biggest part of a inline 1275 to accomplish the job, the crank, main caps, front and rear plates, flywheel, etc., etc., plus you got drill for the palte to fit, so at that point you be best to just use the rest of the inline 1275 as well. I know Swiftune does this with a A+ blocks, not really impressed with their work, it's a waste of time in my book, keep looking for the inline 1275. Try Peter May Engineering in the UK, he race Midgets.
 
Re: convert cooper engine for spridget?

Alright so I guess I'm out of luck, but thnx for the input.

What other cars had the vertical 1275cc engine except midget and sprite?
 
Re: convert cooper engine for spridget?

hmmm... the very early Marina's. Smaller displacement engine were in the Minors, A35, and A40.

I'm thinking your best best is to import one from the UK. Maybe even buy a rebuilt unit since you are paying for shipping.
 
Re: convert cooper engine for spridget?

There even some Marinas that had the A+ inline blocks, rare than hens teeth over here, but maybe not so much over there. The A+ Swiftune engine I went thru for a customer was one of their Road Rocket 1380, they used a Maestro (spelling ???) FWD block, kinda weird, the first clue something is very different is the filter screws right into the side of block, and the distributor clamp is totaly different.
 

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Re: convert cooper engine for spridget?

I thought the A+ marinas were longitudinal engines?
 
Re: convert cooper engine for spridget?

Trevor Jessie said:
I thought the A+ marinas were longitudinal engines?
Click to expand...

I raced with a guy in SCCA nationals, probably one of the fastest Midget racers of all time and he had what he called A+ Marina blocks, and said they were inline blocks to begin, I saw them in his Midget race car, definately A+ block, thats as much as I can tell you. I know a few have converted A+ blocks to inline use as well, I always fiquired we were running these things at 9000 rpms, producing roughly 140 hp, at compression ratios of 15 to 1 and we were not exploding blocks, breaking cranks yes, exploding blocks, no, so what was the use of doing this, I fiquired that was the ulimate test of a A series block, so why bother.
 
Re: convert cooper engine for spridget?

There were several austin vehicle being driven with the inline A series when I lived in the UK in the late 80s. MGs and sprites were pretty rarely seen. Open top cars in a place that rains a lot is not all that practical. To know what you can get you would need to contact a junkyard(dismantler) over there. Some of those guys know and love all that stuff about what fits what.
 
Re: convert cooper engine for spridget?

Trevor Jessie said:
I'm thinking your best best is to import one from the UK. Maybe even buy a rebuilt unit since you are paying for shipping.
Click to expand...

I guess you're right, import is probably my last option.
If I ship from the UK and have the shipper label the package as gift I can avoid import tax and fees but how much to spend on an engine before shipping?
 
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