Which engine is most suited to a Multitronic transmission?

[Hopkins]

Hi,

I am not an Audi owner, but I am considering buying a second-hand A4 or A6 with the Multitronic transmission. The reason for this is just because I like the concept of a CVT, but they've never seemed to be any good until Audi took the bull by the horns!

My question is this: would a diesel engine or a petrol engine be more suited to the Multitronic transmission?

My first thoughts were that a petrol engine would be more suitable because, for a given power output, the engine will be generating less torque. Less torque means less slippage between the chain and the cones.

Then I thought that maybe this isn't necessarily true. Maybe more torque causes the chain to bite more and provide more friction with with to deliver the power more efficiently.

Audi must know the answer to this question, but they don't provide any contact for technical enquiries.

Maybe the difference in efficiency is small, so that the deciding factor becomes another practical consideration like noise, engine response or fuel economy.

Any ideas?

Many thanks!

[Hopkins]

Alternatively, can anyone recommend a "techy" motor forum that might be able to help? I'm afraid that the realm of technical car discussions is not one that I've visited before.

Cheers!

[Hopkins]

Ah well, no luck here! I've found some extra info which I'll post in case it helps someone else. It seems that the German company LuK make the CVT transmission for Audi. Their latest brochure to date on the subject of CVTs was posted in March 2005. It contains some interesting information about how the variator grips the chain with just the right amount of pressure, and how the system can wear over time. It seems to suggest that higher torque engines put more stress on the components, so from this perspective and for a given power output a petrol engine would seem to be the better choice.

I've heard reports of the multitronics needing a replacement transmission as they approach 100,000 miles, in which case the money saved by running diesel instead of petrol might pay for this replacement, negating the benefit of any reduction in wear that a petrol engine would have produced!

Apples and oranges in practice, I expect.

I'd still like to discuss this further with someone though. I've a feeling I'm in the wrong place .

[T-sport]

You would be better off with the Audi manual transmission,Its better and not so problematic as the multitrionic.

[Hopkins]

Hi t-sport, thanks for the reply!

Yeah, I should really consider all the options when buying a car. In which case, I would have to ask how second-hand Audi's compare in terms of value for money to other brands. I have a sort of romantic idea that I'd like to support a technology that I would like to see continue to be developed - in this case a CVT - which is why I became interested in Audi.

The other recently-refined technology that I like particularly is Mazda's wankel engine, but the RX-8 seems to be unfortuantely timed given the rising oil costs. Ah well.

If anyone can enthuse me about some other motoring technology that has been significantly improved recently then maybe I'll stop obsessing about CVT