not a turbo but hope you can help (head/piston help)
Turbo Mini Forums

ok, I just stripped the top off my engine and noticed the valve springs are double not single is this normal for 1275 A+?
Curious now if the head is standard, any tell tales to look for?
How can I tell if it has been modified for unleaded?
Just noticed the pistons are dished down and have a B stamped on the top, is that standard?
all comments and opinions welcome

Looks fairly standard to me.

Whats the ports like in the head?

Looks like a Mg head 1.4" inlets and double springs standard

Metro turbo weekend driver,Mini turbo in the making again!

The B you see on the top of the piston is to tell the guy that machined the bores what size tolerance to make them.

Looks like an MG Metro engine to me. Although I cannot remember if the MG metro engines had dished or flat top pistons?? Anyone??

MG i would say. 29-36 valves double springs & pistons with a shallow dish.

Phil.

WWW.TURBO-MINI.COM

My old MG metro engine (not turbo) had dished pistons

You guys sure the MG had double springs as standard? I know the 'cooper' didn't - but something is rattling in my brain telling me the MG didn't either???

Mr haynes has

1.703 length for the inner
1.740 length for the outer

Metro turbo weekend driver,Mini turbo in the making again!

afaik only the turbos had double valve springs...... im almost positive......

i know this is a really late reply, but im trying to catch up with well over 100 threds at the mo!!!

And on the 7th day........... God created turbochargers!

I'm sure the MG Metros did as well.........

Well the one I had for a bit did anyway!

cheers guys
Looks 100% like I have an MG leaded motor.
Just to move on from the head, I am going to be uprating but not to over 105 bhp. is there any benefit to changing crank to a turbo one?
Cheers
Mark

Nope

turbo crank (barr an early few) are identical to all other a+ 1275's

dont need to rev turbos hard so crank/rods arent all that important

6232 is standard A+ crankshaft, 6581 is hardened "Turbo" crank.

Phil.

WWW.TURBO-MINI.COM

cheers guys

not many 6581 cranks about mind as they didnt use them much. most turbo's had the 6232

Iain - Early ones weren't the 6581 - this appeared sometime in '86 given metros that I've pulled apart - Prior to that was deffo the 6232.

This is what i've found at least - anyone know any different? Did your engine from a 1989 turbo have the 6581 for example???

D

ah i see easily confused me!

end of the day a 6232 does the job nicely for all power levels.

im keeping to a min of 10thou undersize though, no more. i.e. just a reground std crank.