1275 performance

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Stoneporch
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1275 performance

Post by Stoneporch »

Advice welcomed, please, on the easiest way to increase power output from a 1275(marina) engine.
Most years we do a two-week continental tour, and I would like a higher cruising speed for the inevitable motorway stretches. Any suggestions welcomed, bearing in mind that I have very little engineering knowledge, and hate spending money.
Thanks, Stoneporch.
philthehill
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Re: 1275 performance

Post by philthehill »

The 1275cc Marina engine in standard form is more than adequate for your stated requirements. If you have not already done so I would suggest that you change the diff ratio for a 3.9 to 1 unit for more relaxed cruising at motorway speeds.

Matt
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Re: 1275 performance

Post by Matt »

As Phil says, either find and fit a taller diff ratio, or a 5 speed gearbox to drop the revs at the cruising speed.

Any engine improvements will get you there faster, but it will be just as revvy at speed
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les
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Re: 1275 performance

Post by les »

How does that help a guy who hates spending? :D

Matt
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Re: 1275 performance

Post by Matt »

It means he won't spend money on improving the engine and not get the benefit he wants ;)
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Matt
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Re: 1275 performance

Post by Matt »

It means he won't spend money on improving the engine and not get the benefit he wants ;)
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philthehill
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Re: 1275 performance

Post by philthehill »

The OP would have to spend a reasonable amount to improve the 1275cc engine performance whereas changing the diff can be done for around £400 and is a relatively easy job.

https://www.ebay.co.uk/itm/MG-Midget-Sp ... Sw31JfanPT

Stoneporch
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Re: 1275 performance

Post by Stoneporch »

Thanks all. I have,in fact, had a request on this forum for a 3.9 diff for several weeks, without any success to date. I have seen mention of people fitting a metro head- could this give me a bit of extra grunt for climbing very steep hills (like the Alps, which we climbed a few years ago)?
Chipper
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Re: 1275 performance

Post by Chipper »

I fitted a Metro large valve unleaded head to my Traveller's 1275cc MG Midget engine a while ago, after the original head suffered valve guide wear and started burning oil (with lots of smoke on start-up). I immediately noticed an improvement in overall power and torque, not to mention the greatly reduced oil consumption, and it's nice not to have to worry about valve seat recession.

I tried fitting a 3.9:1 diff to mine, but found it didn't give any great benefits for the type of driving I mainly do (local country roads, with lots of hills), so reverted back to the standard diff.

It may well be useful for long motorway journeys though.
Maurice, E. Kent
(1970 Traveller)
Stoneporch
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Re: 1275 performance

Post by Stoneporch »

Thanks for that Maurice. I don't suppose you still have the 3.9 diff?
Richard.
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Re: 1275 performance

Post by Chipper »

Yes, I still have it, and it may be for sale for a reasonable price... Whereabouts are you?
Maurice, E. Kent
(1970 Traveller)
Stoneporch
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Re: 1275 performance

Post by Stoneporch »

Hello Maurice, sorry for the long silence.
I would be very interested in your 3.9 diff. I do,however, live a couple of hundred miles from you in South Yorkshire, so an inspection visit
is not on the cards at the moment.
Is this a diff that you have used and know to be in good condition?
Could you give me an idea of what you would like for it?
Would you be prepared to send it via a courier, if necessary?.

I tried to send you a p.m.-without success.
Regards, Richard.
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