quicky black 202 question

[208_Fireball]

Does anyone know the volume of a stock black 202's combustion chamber volume?

Cheers,

Dave

[LJ38L]

Bore x Stroke (mm): 92.1 x 82.5
if that helps
take a look in a gregorys manual :)

[FastEHHolden]

I'm almost sure they are 55 cc.

[BEV11S]

202 / 6 = 33.6

[gmh265]

combustion chamber volume is not the same as cylinder volume :(

what is the std compression ratio of a black 202? you can work it out from that.

[FastEHHolden]

Its 8.8:1....but I don't know what the piston dish volume is or the actual head gasket thickness (I think its 39 thou).

[gmh265]

your looking at a 70cc combustion chamber (including the gasket)

assuming that the compression figure supplied by holden is true and that holdens figure includes the gasket area as well..

do 202s have a dished piston?

whats the bore size?

[myndphuk]

Originally posted by gmh265
do 202s have a dished piston?


By this I assume you mean a dish in the pistons? (Don't flame me, Im learning!). If so, then NO, they do not have dished pistons from factory. I say this because I have pulled and replaced/changed/swapped 3 heads on 202's now, and they have all had stock/flat pistons with no markings.

Hope this helps.


Cheers.

[208_Fireball]

So anywhere between 55 and 70cc then :)

I need this figure to calculate the compression of the engine, and hence how much i need to take off the head to achieve the compression ratio i want for the engine...

Does anyone have a blue/black head off their engine they can measure?

Cheers,

Dave

[gmh265]

well you obviously have a 202 head so why don't you measure it?

or work it out, 70 cc minus the volume of the compressed gasket

I can't do it for you because I don't know the bore size!!

[208_Fireball]

If i don't get an answer by the time the head can come off again, then yes, i will measure it myself. If i can find out the value beforehand, then it saves trouble. Asking here is not causing too much trouble (i hope!)

Cheers,

Dave

P.s., it seems that all the blue/black engines have a small dish in the pistons also.

[208_Fireball]

OK, for anyone that wants to know, the stock chamber volume is approx 58cc, and once 30 thou is shaved off it, it brings it to approximately 50cc...

Cheers,

Dave