The Triumph Dolomite Club - Discussion Forum

Aluminium flywheel? What do you all think? It's for my 1500 dolly and will have a tricky cam and a "special head". I'm not racing but I want an engine that won't break if I did want to gun it. I've found a local race engine builder who's got balancing equipment to take it within 0.1grams! Those new bearings that were recommended from paddocks combined with a nitrided crankshaft should keep revving for some years to come. But do we think the aluminium flywheel is the best route for a street car? I suppose it's worth asking if anyone has a special flywheel that they'd sell?

It's a nice idea in theory, but a flywheel is there for a reason! With a very lumpy cam and a very light flywheel, you may find that that the engine is unbearably rough and lumpy at low revs and may not idle at all - or at least not below 1500 or so rpm. Much cheaper too, to take a pound or two off the already fairly thin steel jobbie. Especially for what is basically a road car.

Steve

Thankyou, decision made. That's what I wanted, some advice from someone who knows their stuff and seeing your many other posts I would say that you do. Plus it saves me some money.

marko wrote: I'm not racing but I want an engine that won't break if I did want to gun it.

I wouldn't use a 1500 then.

Mark, I have no experience of aluminium flywheels myself but have read that they aren't very durable
because over time their mounting holes can become stretched.


A viable way to lighten the load on your 1500 engine is to fit a lightweight alternator.
Some ingenuity may be necessary for mounting it and the wiring for the plug will need altering as well.




Ian.

The main negative from a road car perspective is that they can be overly light and as such you'll struggle to get a nice smooth idle on them. You'll also notice the relative lack of torque and driveability. The reason racers use them is that it enables the engine to rev up more quickly primarily and also it reduces rev drop when changing gear, the lack of low down torque is not really an issue when you're racing at high revs. I wouldn't use one in a road car but it may be worth lightening the standard one a bit if you have it out anyway.