A+ Nominal sizes???
Turbo Mini Forums

Hi All....

Wondered if you know and could tell me the nominal figures for the below on a STD A+ engine?

A) Gudgeon pin ctr to piston crown? (38.81mm?)
B) Con Rod Length Ctr to Ctr?
C) Stroke? (i think 81.28mm)
D) Block Deck to Crank C/L?

As i need to know a few things for an engine im planning on building to see if it will stack up right. need to see if block has been skimmed.

ALSO..
Am i right in thinking...
(A+B+(C/2))=D....

And the difference is the Deck to crown height? Yes?

And if (A+B+(C/2)) > D... then there is a problem?...

Cheers
Ross.

Sooperdooperturbocooperexpertengineering!

B is quoted as 5.75" so 146.05mm?

i measured D as 225mm but i don't know if the block had been skimmed, plus it was with a ruler...

accralite quote A as 38mm.

i thought C was 81.33mm

yes the difference is deck height,

on std engines the pistons will be down the bore a bit, i seem to remember a measurement of 20-30 thou.

ideally pistons should be flush, if you find yours do stick out a tiny bit you could have a bit taken off them.

i had a std piston that i measured to be 38.81, thats wghere i got that from, but 20659 (1380 pistons) measure 37.73.. the hypatecs i have are 38.70 so need a nominalSTD figure there.

i had a rod measured a while ago that was 146.45, so close to what u have but still nearly 1/2 a mm.

need to do more measuring!!
Cheers
Ross

Sooperdooperturbocooperexpertengineering!

This may answer "A"

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=121851

website:- http://www.terryhunt.co.uk

Yeah cheers for that, interesting reading, does seem to suggest 38.8 is std size, now need to find out nominal block thickness!

Sooperdooperturbocooperexpertengineering!