lightening flywheel

[Skufy]

Remembered there was a sep. forum for engine questions so here goes the second.

How much would a standard 1600 or 2000 lancia flywheel normally be lightened by, would this require balancing or even balancing with the crank?

[Wallace]

Guy crofts book gives a number for how much to take off . . . .I'll have a look tonight for the figure .. ballancing always a good idea if the engine's in bits . IMHA . . especially if the flywheel's been effectively weakened a bit my lightening.

Barry Waterhouse did mine (before I had a lathe ! ). No cracks after 20k miles, reved up to 7500 on several occcasions and it made a big difference when "blipping" the throtle . . and still easy to drive as well ! (not too-oo light .. ). I'll measure that one up when I get a chance.

[Skufy]

Excellent, I look forward to the dimensions. It did occur to me that the Lancia flywheel could already be on the light side. As for blipping the throttle.....eh....... me too.

[omicron]

Balancing has to be done after lightening.

I took 2kg off my standard Monte flywheel. I'm sure more could have been taken off, but its better to keep on the side of caution.

[Wallace]

Mr croft states standard flywheel (2 litre) - 8.4 kg

Croft lightened standard - 7.1 kg

The EN8 one I've made (see my photo album) - 5.8 kg

[omicron]

my standard one was 7.5kgs, now 5.5kgs.

[Wallace]

Brave man !

I'll measure up Barry Waterhouse's one this week . . .

[L666EVO]

I've recently had a billet steel (EN24) flywheel made for my Beta engined Strat replica, weighs about 5.5KG, plus with a much lighter twin plate clutch, not had it running yet, I'll let you know how it performs soon. As Andy says, you definitely need to balance the whole crank/flywheel assembly if you are removing a lot of meat from the flywheel. Plus put a couple of dowels in the end of the crank to help remove some stesses from the bolts, I think all 2 litre cranks have the holes already machined.

Cheers,
Chris

P.S. I have a standard weight steel billet F/W for sale if you are interested, which could be lightened if required.

[Skufy]

I'm budget playing with some betas until I get my hands on a Strat replica or possibly a montecarlo, possibly interested in the flywheel but not for a long while yet.

[monte_giallo]

I've taken my standard flywheel down to 6kg.

I have revved it 8,000rpm.

Do you think I ought to fit a shatter guard?

Paul

[Will]

...it should also be noted here that PBS made, and may still make, a 4-1/2lb or so aluminum flywheel, and if you can get your motor smooth enough to keep it running on the crank inertia alone, you could fit a flexplate from an automatic in place of the flywheel. Craig Hargiss here in the US mentioned that he's done this on a Beta coupe, I haven't tried it, so don't ask me how! I was thinking about it, because the larger SC ought to serve the funtion of a flywheel, more or less. If anybody has an "idiot's step-by-step" to making this work, I'm all ears!
-Will

[monte_giallo]

That's what I'd like, Will: the Ford twin-cams/BDAs etc here do this. I can't see how such a flywheel can take the pressure of the clutch, though. I'll ask my Ford guys.

Paul

[cthargiss]

The flex-plate is there only to hold the ring gear for the starter.. It is bolted between the crankshaft and a small diameter(5 or 6 in) unitized multi-disc racing clutch. The flex-plate takes no load from the clutch, as the bolts pass through the clutch, then the flex-plate and into the crank. A custom throw-out needs to be fabricated. The last time I did this, in 1990, it cost about $5K.
Craig

[Will]

Ah....thanks Craig- that explains a lot! I had the same question, as I've never taken a look at one of those "unitized" clutches you mention!
That sounds more expensive than it ought to be, what am I missing? Is the clutch itself like 4K or something? Making a TO bearing and carrier doesn't sound like a huge deal?
-Will

[cthargiss]

And I thought that it was cheap at the time! Now days, anything that says AP Racing on it is $$$$$$$! As to the throw out, I had to fabricate the whole system to convert from push to pull, with only 2in from the end of the clutch to the back of the bell housing.
Craig