Alley Flywheel

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meadowhog
Posts: 392
Joined: Fri Dec 16, 2011 1:50 pm
Location: South Bucks

Alley Flywheel

Post by meadowhog » Fri Dec 06, 2013 6:11 pm

I need to replace my ring gear and thought I may as well go for an alley flywheel with a ring gear on it. I assume theyre all 13".

Does anyone know of any problem in doing this? 157 or 160 teeth doesnt seem to be a problem but whats the rules on balancing and does a standard clutch fit??

I have a 1965 302 and Im looking at buying http://www.ebay.co.uk/itm/SMALL-BLOCK-F ... _42wt_1203

Tomaselli
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Joined: Fri Sep 30, 2005 2:03 pm
Location: Cheshire, North West England

Post by Tomaselli » Fri Dec 06, 2013 9:19 pm

I have it in mind that a 'lighter' flywheel gives up some bottom end torque, but I could be wrong with the V8 as I recall reviewing this with my Holbay H120 engine :mrgreen:

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redbaron
Posts: 111
Joined: Sun Aug 16, 2009 6:18 pm
Location: Essex

Alley Flywheel

Post by redbaron » Fri Dec 06, 2013 9:48 pm

Hi Meadowhog,
Why do you not replace the ring gear on your present flywheel,this flywheel is presently balanced to your engine,or should be.
If you buy a new flywheel and ring gear it will not be balanced to the crankshaft and front dampener on the engine.
Changing the ring gear is not a hard job for a competent machine shop.
By changing to an alloy flywheel it will allow the engine to rev easier at the expense of some idle quality.
The clutch bolt patterns should be pre drilled the same.

Regards David

meadowhog
Posts: 392
Joined: Fri Dec 16, 2011 1:50 pm
Location: South Bucks

Post by meadowhog » Sat Dec 07, 2013 12:49 am

Hi guys,
As Tony says. I too 1st did this with a Holbay which made a hell of a difference. More of the engines power is used to drive the back wheels instead of accelerating a big lump of spinning steel. Years ago I was talking to a Rolls engineer who had a calculation which explained that dropping X amount off the flywheel was the equivalent of X times Y weight off the weight of the car. On a 1725 it was very noticeable but on a 302 it may well be negligible

I think the loss of torque thing is more to do with less rotation mass to get the wheels spinning and so may seem like a loss of torque but actually there's simply more power available to the back wheels once the clutch is dropped and the wheels stop spinning.

I may just change the ring gear as you said D. have you got one?

Tomaselli
Posts: 942
Joined: Fri Sep 30, 2005 2:03 pm
Location: Cheshire, North West England

Post by Tomaselli » Sat Dec 07, 2013 11:43 am

meadowhog wrote:but on a 302 it may well be negligible
Agree with you Simon, I have to check with my specialist but I'm sure I have a lightened flywheel in the Tiger - I must have as it revs like a motorbike engine and the throttle response is pretty much instant. :mrgreen: With modern components now available to us, a lighter and internally 'balanced' would produce results.

Interesting thoughts on 'balancing' there from the Baron.

bigbob
Posts: 379
Joined: Wed Aug 19, 2009 11:31 am

Post by bigbob » Sun Dec 08, 2013 6:17 pm

I assume they come with a steel insert wearing disc. I went the other way and changed from cast iron to steel as heat build up from 570lb torque and Spec 3 clutch cooked the old one causing warping and crazing. Will the aluminium cope ok with heat from everyday driving?

meadowhog
Posts: 392
Joined: Fri Dec 16, 2011 1:50 pm
Location: South Bucks

Post by meadowhog » Sun Dec 08, 2013 11:24 pm

Yep, steel insert. With only 570lbs of torque steel billet is pobably the best idea for daily driving!
Decided not to go alley for now. Ill check the motor over see what its got and go from there. £20 standard ring instead of £300 inc balancing is still good but i may spend that on something else. I might even sell the HiPO heads and get alley ones. They seem to be fetching monster money too now.

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