Help with piston part no.
Turbo Mini Forums

Hello, had these lieing around for quite some time now.

can anyone shed any light as to what they are ?

21962 g7 r07

Thank you kindly

Edited by Custard on 17th Mar, 2010.

Dave the Cake

Standard Late A+ low compression (9.4:1) piston

how do you know they are +20?

Edited by Sprocket on 17th Mar, 2010.

I was given them in a half built engine. so i measured the bores, cant remember what the measurement was now, but im sure at the time i worked them out as being +20 ...

sorry not very convincing i know, ill check tonight, just a bit buried.

should they have a marking to say they are then ?

Would they last in a forced induction engine ?

Thanks again!

Dave the Cake

is that the same as what nick bud is running ?

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

I think Nick has 21253's in his.

If something is worth doing, it's worth doing half of.

They should have +0.20" on them somewhere if they are +20s.

https://www.facebook.com/pages/Fusion-Fabri..._homepage_panel

www.fusionfabs.co.uk



1/4mile in 13.2sec @ 111 terminal on 15psi

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

21963 is the Cooper A+ high compression piston

The 21253 is almost, if not the same piston. Side by side you would be hard pushed to tell one appart from the other.

Edited by Sprocket on 17th Mar, 2010.

Right it would appear im a massive fail, they are only standard Size.

So is the 21962 piston the equivilant of the 21252 piston which is rubbish with forced induction ?

Thanks for all the help. Much appreciated

Dave the Cake

No the 21962 piston is the same as the 21963 or 21253 pistons, but with a reduced crown hight to give the lower compression. They are good pistons, however, they wont take any more abuse than the 21253s would. It will also depend on the mileage the pistons have been exposed to as to how much they have been stressed, as to how long they would last before they failed, if they failed at all.

Basicaly, you can use them, and the engine will work, but for how long at what boost is any mans guess. I suppose it depends on how you intend to use the engine. Long cruse journeys, and short bursts at full throttle will put less demand on the piston than bombing round a track at full throttle all day.

Thank you Sprocket top man!

Its only my toy car and doesnt get thrashed. Just cruise around the countryside really.

Taa

Dave

Dave the Cake

if it's any reassurance i've done over 30k on my 21253's running 15psi and about 300 running 20psi so far.

its hugely reasuring Nick! i hope my engine goes aswell as yours

cheers

Dave the Cake

what do you rev that bad boy to nick?

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

only 6.5k at the minute, i want to give 8k a try to make use of the turbo but i fear i'll need a different cam and a worked bottom end as its all std atm.