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MG MG Y Type - engine swaping a YA?

I've been thinking about repowering a YA with an MGA 1600 or MGB engine to make the car more drivable on
busy roadways. I'm interested in opinions and past experiences on this subject.

My 2 cents worth. Don't do it. The Y is essentially a pre war car built post war and for different driving conditions. I am lucky I live in a part of the world where I can drive my YT on roads that it was meant for; without long streches on motorways, freeways, or intersates, but from the miserable times I have had to spend on them I can understand the temptation. Changing the engine is only the begining and you will also want to change the gearbox,brakes, wheels,tyres and suspension. Then you will not have a Y. My interest in MG cars derives in part from my long standing interest in antiques and it is black letter law that an antique that is original is far more sought after than one that has been altered. I think that applies in the future to our cars. Terry
Terry O'Brien

If you have a left-hand-drive 'Y' series, a 'B' series engine from a MG Z Magnette, or MGA, or MGB can be adapted to fit, but there are problems with the clutch bell housing that means you will also require the other cars gearbox. This means cutting the grearbox cover about, and adapting the gearbox mountings. The 1800cc engine is far too powerful for the 'Y', ( but you can fit MGB disc brakes and most of the front suspension to get round this.) Higher ratio diff from the TD rear axle will be needed.

If you have a rhd 'Y', then there are serious problems fitting a 'B' series engine as the steering column goes through the middle of the distributor. Not good for the ignition.

There are a few 'B' series engined cars in the USA. It need not be from another MG model, there are about 70 UK models that used the engine. ( List if you want from me on < > )

Neil Cairns

Hi, if I were in your position, I would would upgrade that sluggish XPSC engine (46 hp) to XPAG specs (54 hp) or to XPAG stage two specs.(57 hp) and change the rear axle ratio to 4.55 from 5.143. The rear axle ratio change is commonly done on T-series cars, generally to 4.55 or to 4.3. The cars now become very driveable at 65 or 70mph. The YA is only 100 or so lbs. heavier than the TD, but the aerodynamics of the TD are better than the YA.
For the change in rear axle ratios, I would look at using a Morris Minor 4.55 center section which should bolt onto the YA axle housing after the flange holes have been re-drilled. The YA spider gears would need to be used but, suprisingly enough, they will fit right into the Morris carrier. This procedure is often done on MG-TC's whereas for a TD or TF the procedure is to change the crown wheel and pinion only.
It should be noted that all these changes are totally reversible and the YA can easily be returned to the way it came from the factory.

Hugh Pite
Hugh Pite

There is a guy in Australia running a right hand drive YA with a supercharged MGB engine fitted in it an based on Niels comments must have taken an awful lot of work to fit. (I fitted a B series in my TD and it is a MUCH easier car to convert.)

If you want more power and driveability a more sympathetic modification would be to rebuild th engine and fit a superchager designed to bolt straigt on to an XPAG motor and provide similar HP to a B series without the expensive structural and body mod.s required, noting that improved brakes and a taller Diff would still be needed to fully transform the car.
Phil Stafford

I agree that a supercharger would be the way to go if you could find one (E-bay?) or afford one ($1500?). Evidently you get 69 HP out of a stock XPAG motor using a "Shorrock" supercharger. A big plus is that you get a large increase in power at the lower and medium engine speeds whereas a stage 1 or 2 tune gives the biggest increase at high engine speeds. By the way, I made a mistake in my last posting. Stage 2 tune on an XPAG motor should give 64 hp and stage 1, 60 hp.
As an aside, if you were really keen you can get nearly 100 hp out of the poor little XPAG by using the supercharger, messing with the head and running on 80% methanol.
Hugh Pite
Hugh Pite

This thread was discussed between 04/12/2001 and 05/12/2001

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