Author Topic: 1962 piston compatability  (Read 1605 times)

Offline lefty

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1962 piston compatability
« on: 15.10. 2008 21:56 »
hello all,
i'm just beginning a restoration of a 1962 bsa a7 basketcase, and hoped someone could tell me what pistons were compatable for both standard or slightly higher compression? i have to resleeve the barrels, so any reliable option which is affordable and won't need further maching i an option.
I'd also like to hear your opinion of which engine mods come the most highly recommended?
thanks
leif

Online bsa-bill

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Re: 1962 piston compatability
« Reply #1 on: 15.10. 2008 22:04 »
remember that the sleeves will need bored to suit the piston, overall it will cost twice as much as a rebore ( if you have enough metal in the barrel)

All the best - Bill
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline lefty

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Re: 1962 piston compatability
« Reply #2 on: 15.10. 2008 22:11 »
yep, i realize this, but i'm already short one piston - likely the one which disintigrated and knocked a chunk out of the bottom of one of the liners, so new pistons, liners and a rebore are all neccesary at this point. luckily the rods appear to be in fine shape....and other than regrinding the big end, the rest looks alright too. so, yeah, total bottom end rebuild, and top end too. ouch!

Online bsa-bill

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Re: 1962 piston compatability
« Reply #3 on: 16.10. 2008 14:56 »
Well that'll keep you busy for a while, lighten the old wallet a bit too, but you can't take it with you so you might as well enjoy it.

Good luck
All the best - Bill
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline RichardL

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Re: 1962 piston compatability
« Reply #4 on: 16.10. 2008 15:38 »
Leif,

I think the good news here is that standard diameter pistons seem to be the most redily available, as most engines are already working on their 2nd or 3rd rebore, thus, the demand for those pistons seems higher. Having the new sleeves would seem to bode a long life ahead for your A7.

Richard

Offline dpaddock

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Re: 1962 piston compatability
« Reply #5 on: 16.10. 2008 16:02 »
OEM standard pistons are 8.1 cr, p/n 67-1442, and 8.5 cr, p/n 67-1558.
Increase the last numeral in the p/n by '2' for each 1/2 mm oversize,
David
'57 Spitfire