right just put a ring down a bore while i have got my engine stripped (about an 1and half inch down) to take a reading what should i be getting before the rings need changing.?????

i measured 0.8mm that about 0.031 thou

am i right in thinking this is to big i was thinking they should be about 12-14 thou..

 

What pistons and rings is it?

30 thou isnt the end of the world, but is more than normal on most engines.


Have you measured it at other places too to check for taper?


The bores have just been honed I take it?


Have you checked your piston to bore clearance?

 

is the ring square in the bore?

 

cossie motor yb tryed n diff places them reading were about the bigest ....

bores not honed yet but will be if fresh rings going in....

pistons still seam very tight...

 

good point


To ensure that it is, i use an inverted piston to push it down in the first place.

 

Yip used a digi vernia to make sure it was sitting level....

 

Ok mate.

The gap will be a few thou bigger still after honing

Measure them

 

What just put feeler gauge down side of piston and bore????

 

have you measured every ring in every bore? you may find you can mix and match to get the rin gap you like?

 

No, set a caliper to the same size as the piston, and place a dial gauge into it and zero it.

Then run the dial guage up and down the bore and observe the clearance at various points.

Measure it in multiple directions too, ie front to back and side to side.

 

I do this, and then hone the bores different amounts in order to even them up too if needed.

 

no.... i was going to put some more rings in the freshen it up but just thought id measure the rings that were in to see how worn they were....

 

Ah, this is the OLD rings you have measured then mate?

That doesnt sound too bad in that case.


Is there a lip at the top of the bore?

 

whey over my head ( not got the tools )

the engine is strpped down as i lost oil pressure so it got new oil pump new shells/ mains thrusts on a freshly ground crank but while it was stripped down i was going to get a bit work done to it ie 7,2-1 pocketed pistons (.25) on a fresh rebore and get some head work done so i can fit a gt30 but now i going to put it back together untill i got all the bits ie turbo, injectors, cams, ect ect

I got the pistons now but would like o put engine back together now and do all the work together and get all the machining done together...( next winter ) so i was thinking about putting some fresh rings in as i am running 32psi now....

 

not really still got hone marks on bore's off when it was rebuilt....

It a 200 block with standard size pistons and it was a std/std crank till i got it reground so i was thinking it might have been rebuilt off a new block because of it still having the hone marks>>>>>

 

You really need to measure the piston to bore clearance to decide if its in need of a rebore and oversize pistons or not.

But based on what you have said, im sure you will get away with it for a good while if you just hone it and slap the new rings in.

 

cheers mate think ill do that.......as soon as i got all the bits my new pistons will be going in with a fresh rebore.....

Was going to put them in now but rather get all machining work done together