Low compression pistons...

[Resto-Rob]

Hey guys,
Since i am forced to rebuild half my 53 plungers engine i was thinking i might as well have a bit of fun with it.
I currently have low compression pistons and have been thinking about running standards insted.
And yes, i have thin flanged barrels, hence the hesitation to just bung them in.

What do you guys think?
Is it safe to run the standard pistons or should i stick with the low comp?

I am just looking at improving the crusing speed a fraction.

Cheers :)

[muskrat]

G'dat Rob.
7.5:1 and a 356 cam would be a safe upgrade.
Cheers

[orabanda]

I agree with Musky.

[Brian]

I would also recommend that combination. You will still have a nice smooth engine but with just that bit more go.

[Resto-Rob]

Brillient!  Then thats the way i will go :)
Thanks guys! :)

[Resto-Rob]

I am finally ready to start my rebuild!! But first another complication made me question the "power" upgrade... i have a SJ crank that has been taken down to -40.  Is it still recommended to up the compression?

[muskrat]

I don't think it would be a problem for day to day riding, just don't try to do the TON too often!!
My A7SS racer had a SJ crank running 13:1 on methanol and reved to 8k. In 9 years only broke 3.
Cheers

[bonny]

Speaking of low compression pistons (6:1) , is there anywhere where these can still be bought or is anyone reputable making them ? 

[trevinoz]

Why would you want them? I think that they were 6.5:1 and were suited to the low octane fuel of the day.
Eventually BSA went to the flat top 7.25:1 pistons as standard which are quite suitable today.

Trev.