My Advice and our company policy on Dual Mass Conversion Kits
Obviously whether to use a dual mass conversion kit is a balance between gain and pain. Is the cost saving worth the worry? We as a company will not advise their use. The Ford Fiesta 1.4 TDCi is an exception as they were factory built with both solid and dual mass flywheels. By changing it to a solid flywheel is not really a conversion but an O.E. change. The engine on this model is only 67 Bhp and below the 100 Bhp safe limit. This 100 Bhp change over point is seen again when looking at the Ford Focus 1.8 Diesel 89 Bhp models solid flywheel, models over 100 Bhp are fitted Dual Mass. In our opinion If the car did not need the dual mass flywheel the boffins who design engines and gearboxes wouldn’t ask Sachs to design and build one for them.
When could the gain be worth the pain?
1. When the engine is not running as new or been uprated power wise.
As the dual mass is designed to take out the engine vibration transmitted towards the gearbox it will not work if the engine characteristics are changed probably causing premature failure and repeated replacement. If engine power is more important or the cost of a new engine prohibitive then a conversion kit with its possible side effects could be the best solution.
2. When the repair is uneconomical.
Say the car is a VW Polo 1.9D 96 -
There is a place for these kits but because of the problems that have been associated with them such as :-
1. Gearbox input shaft bearing failure.
2. Engine crankshaft shearing off.
3. Gearbox gear chatter.
we prefer not to supply or use them.
If you feel on balance it is the best option at least use one supplied by VALEO the market leader and a quality product.