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AEC 11 litre engine in a Routemaster

Hello all,

If an 11 litre AEC engine is fitted to a standard Routemaster, which otherwise has all its original specification components, will any of the components be subject to additional, damaging stress?

I would have thought that even the starter motor would be subject to additional stress turning the larger engine. Then what about the other drive items?

What speed / pull advantage would having the 11 litre engine with the standard diff have to the 9.6 litre standard unit with the standard diff?

Thanks all,

My bus number (if any): Searching for a bus

Re: AEC 11 litre engine in a Routemaster

The starter is the same on most AEC engines.

You may not get any more top speed unless the bigger engine revs at more than 1800 rpm.

There is obviously more torque and stress on all transmission component, but some RM/RMLs were built with 11.3 engines so should be capable of withstanding those stresses.

You will notice the extra horses going uphill and maybe pulling away with a load on.

My bus number (if any): RML2532