Balancing pistons

[ebola]

Im trying to balance my 2.2 mahle pistons. After proper cleanup, appeared that difference between lightest and heavyest is 6 gramm! First I was thinkin to balance them with perfect size od 0.1 gram, but there is not enough material inside piston to grind off for 6 grams! Then I took pins and retainer springs, weighted them and placed heavyest one to lightest piston and opposite.Pins are very similar in weight and not much help from them. Finaly, with my best believe of how much I can grind off, Ive got 1 gramm difference.Now Im going to put rings on and will see - maybe I can get even closer if lucky? Do you think 1 gramm is ok - a lot or good enough? Thanks.

[glhsken]

You balance the entire rotating assy, not just the pistons, but pistons rods pins clips.

[BoostedSC]

Sorry to hijack the thread, but my question is along the same lines. I've read that removing the balance shafts on a 2.5 causes some ?mild? vibrations at idle speeds. Has anyone had there 2.5/no balance shaft motor balanced by an engine shop?? If so, has it eliminated the roughness at idle??

Again sorry to hijack the thread.

Tom

[xjjunkie]

on our style engines, it's internally balanced. meaning you make all the rods weight the same, and do the same with the piston assemblys. (piston,pin,clips). if you have someone in the area that can spin balance a 4 cylinder crank, then you get your bob weights and hang them from each journal and spin the assembly to determine if you need to add or take weight out of the crank.


scot

[turbovanman]

Quote:

Originally Posted by BoostedSC Sorry to hijack the thread, but my question is along the same lines. I've read that removing the balance shafts on a 2.5 causes some ?mild? vibrations at idle speeds. Has anyone had there 2.5/no balance shaft motor balanced by an engine shop?? If so, has it eliminated the roughness at idle?? Again sorry to hijack the thread. Tom

I took mine out and at idle, there is alot of vibration, especially with the a/c on, but I am running heavy duty mounts so they transmit more vibration. I am installing a short block with balance shafts in for a temp measure so I will have a back to back comparison. In stop and go traffic, the vibration is fricking annoying and my engine was balanced.

[neon_steve]

I have a 2.5, no balance shafts, and the only vibration I had was #3 missing slightly due to lack of fuel(I know this now from hindsight and a hole in a piston) The motor didn't nessesarily vibrate at all other than a very slight miss which you could hear in the exhaust.