Author Topic: Iron head/Alloy head  (Read 1148 times)

Offline 60 blue flash

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Iron head/Alloy head
« on: 27.10. 2010 20:52 »
Hi Guys,
Im new to the forum so please be gentle! I have an iron head 1960 A10 and love the low down torque and mid range but fancy a bit more up the top end. As far as im aware everything is working ok with no concerns. Can i rework my iron head fitting larger valves from a road/super rocket or would i be better off fitting an alloy head?
   If there are any other options to releasing a bit more power with the std set up and without spending loads or major strip downs i would love to know

1960  Golden Flash
1957  B33
1963  Velocette Metisse
1961  Velocette Venom
1960  Velocette Venom (my dads bike since 1962)
1959  Velocette Venom
1953  Matchless G3LC
1949  Triumph  5T
1949  Matchless  G80
1946  Matchless  G3
1936  AJS 36/26
1930  Douglas  S6
1929  AJS Model 9

Online Brian

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Re: Iron head/Alloy head
« Reply #1 on: 28.10. 2010 00:17 »
Welcome aboard 60 blue flash.

It depends on just how much performance you want, if you still want a nice tractable motor but with a bit more go and dont want to spend a fortune I would suggest going up slightly in compression, std is 6.5-1 so go up to 7.25-1 and go to a 356 cam.

I know it means pulling the motor apart to fit another cam but fitting larger valves with either a iron head or alloy head wont give you any advantage with the standard cam (334). If you fit the 356 cam at some time in the future if you decide to go to a alloy head you will already have a suitable cam fitted.

Online trevinoz

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Re: Iron head/Alloy head
« Reply #2 on: 28.10. 2010 03:31 »
If it is an untouched '60 model it should have a 356 cam fitted from new.
Trev.

Online Brian

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Re: Iron head/Alloy head
« Reply #3 on: 28.10. 2010 04:17 »
That will teach me not to check the parts book first. Trev do you know if it would still have been fitted with the 6.5-1 pistons or 7.25-1. Assuming it is still all standard. My 61' had 6.5-1 in it when I got it.

You could have a look down the plug hole with a torch, if the pistons are dished on the top (concave) then they are the low (6.5-1) compression type.

If you have a 356 cam and 7.25-1 or more and you still want more performance then I guess it comes down to how much do you want to spend.