piston machining

[turbojolt]

how much roughly will it cost to get 4 1.2 pistons pocketed

[Adam]

£50-£60

But why?

[turbojolt]

i was told is i want to put the 1.3 sr crank shaft and rods on my 1.2 i will need to have them pocketed

[burgo]

all depends on your local engineering shop. only way to find out is to ask. im sure paid £60 tho

[ck]

who told u this? im not sure myself but the piston does not protrude past the block on both engines, and providing it still doesnt then why would you need to pocket the pistons? ive never heard of them being pocketed for very lairy cams...

[turbojolt]

mowgli said when he had a 1.3 and bored the block to accept the 1.2 pistons he had to have them pocketed

will i not need to do this if i start with the 1.2 block

[burgo]

turbojolt the only way of knowing is measuring and dummy building. just because on has to doesnt mean the other does

[mowgli]

turbojolt.

re-read my original answer., you have to measure everything & be a competent mathematician to do the sums to get the pocket right.
my intention was to get a reasonable compression ratio so I could run reliably on unleaded.

the original PMC 1.4 conversion, which was my inspiration, actually came with pocketed pistons. if left at the stock shape, you had something like 11.75:1 cr

[turbojolt]

turbojolt.

re-read my original answer., you have to measure everything & be a competent mathematician to do the sums to get the pocket right.
my intention was to get a reasonable compression ratio so I could run reliably on unleaded.

the original PMC 1.4 conversion, which was my inspiration, actually came with pocketed pistons. if left at the stock shape, you had something like 11.75:1 cr

with that kind of compersion would i have to run it on super unleaded

[matthew172]

when he had a 1.3 and bored the block to accept the 1.2 pistons

wtf?? sureley if it was a 1.3 then the pistons would be bigger than 1.2 items anyway so therefore no need to bore the 1.3 block if theres nothing bigger to be put in place

[turbojolt]

nope the 1.2 pistons are bigger

[mowgli]

the 1.2 is big bore short stroke.
the 1.3 is small bore big stroke.
mix them up & you get a 1.4 that an f10 gearbox will fit to & has a small engine number......

[burgo]

wtf?? sureley if it was a 1.3 then the pistons would be bigger than 1.2 items anyway so therefore no need to bore the 1.3 block if theres nothing bigger to be put in placeneeds to read up on how engine displacement is worked out