While I was recently sorting through my years of accumulated spares, I thought it would be fun to pop a selection of flywheel and crankshafts on my (digital) bathroom scales. For posterity here are the results
One phase 2 (i.e machined all over but holes bored in crankpins) 10.9Kg
Two black sided shafts both 11.6Kg
Three Oval web, one early, two late all 12.55Kg
A selection of flywheels all 10.9Kg.
There are many who claim that the later Javelins lacked the verve of the early models although to me this has always been unclear whether this was the response of the engine or outright performance, given that the car reputedly put on weight with better interior appointments etc. Certainly it strikes that taking a bit of weight off the flywheel is not a bad thing, even for the non competive motorist.
Nick
Crankshaft weight.
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Nick Webster
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Crankshaft weight.
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Re: Crankshaft weight.
You can shave a huge amount off the flywheel with little affect on smooth running. It almost seems Jowetts thought they were still building a 2 cylinder.
Of course, the heavy rotating weight not just in crank and flywheel but all the transmission, wheels and tyres is a huge loss in energy as you have to accelerate it AND decelerate it. It is not just rotational energy but kinetic as well. It also slows gear changes as you have to wait for things to change speed.
Of course, the heavy rotating weight not just in crank and flywheel but all the transmission, wheels and tyres is a huge loss in energy as you have to accelerate it AND decelerate it. It is not just rotational energy but kinetic as well. It also slows gear changes as you have to wait for things to change speed.
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David Morris
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Re: Crankshaft weight.
Hi All,
Keith is absolutely right about reducing the flywheel weight on the Javelin and Jupiter engines. My car, previously owned by Ken Lees, who was an erstwhile Competitions Secretary in the club, has the flywheel so reduced in weight that it has lost the flywheel TDC and timing marks completely! There is just enough thickness left to hold the ring gear!
She doesn't suffer from rough running and doesn't seem to mind losing the weight, compared with previous Javelins I have owned over the past 55 years I have been playing around with Jowett's. I still have my letter from Jowett's dated 1964, saying that they were sorry, but that they would shortly be ceasing support and suggesting that I might seek help with spares from independent stockists, such as a Mr. Mitchell, Mr. Dodds and Mr. Moar. They added that there were still several garages that might hold spares and that the Jowett Car Club were an excellent source of support and friendship. I joined immediately!
My Javelin is a Standard and I have been told that Ken used to throw her around without mercy in competitions, back in the 1960's. One weight saving feature that Ken might have appreciated is that she was, when owned by Ken, fitted with the Standard seats in vinyl, which are much lighter ( and much less comfy! ) than those fitted to Deluxe models. If you have ever struggled to drill the floor for the mountings and fit the front Deluxe bench seat into a Javelin on your own, you will know what I mean! They are incredibly heavy.
All the best,
David
Keith is absolutely right about reducing the flywheel weight on the Javelin and Jupiter engines. My car, previously owned by Ken Lees, who was an erstwhile Competitions Secretary in the club, has the flywheel so reduced in weight that it has lost the flywheel TDC and timing marks completely! There is just enough thickness left to hold the ring gear!
She doesn't suffer from rough running and doesn't seem to mind losing the weight, compared with previous Javelins I have owned over the past 55 years I have been playing around with Jowett's. I still have my letter from Jowett's dated 1964, saying that they were sorry, but that they would shortly be ceasing support and suggesting that I might seek help with spares from independent stockists, such as a Mr. Mitchell, Mr. Dodds and Mr. Moar. They added that there were still several garages that might hold spares and that the Jowett Car Club were an excellent source of support and friendship. I joined immediately!
My Javelin is a Standard and I have been told that Ken used to throw her around without mercy in competitions, back in the 1960's. One weight saving feature that Ken might have appreciated is that she was, when owned by Ken, fitted with the Standard seats in vinyl, which are much lighter ( and much less comfy! ) than those fitted to Deluxe models. If you have ever struggled to drill the floor for the mountings and fit the front Deluxe bench seat into a Javelin on your own, you will know what I mean! They are incredibly heavy.
All the best,
David