Tolerance on wrist pin bore

[the_skin_eater]

Im gonna put some 2g pistons on 1g rods...

I know the end has to be opened up to 22mm...Whats the tolerance on this??? I ask cause the machines here at work are old, and they dont run as true as they used to.
I also dont want to pay to have someone else do these when I can do it here.

I was thinkin about using our edm machine, but ehh, more work than its worth.

So ya, just wondering. Need these soon as its the only thing holding back my engine rebuild. Just want to know if it has to be frikin perfect, or as long as its press fit in the holes it will work.

Thanks. Oh yea, need this soon, gotta order the reamer by tonight.

 

[BISHILVR]

That is a critical fit. If your tools are'nt up to spec then just send it out. The factory service manual does'nt list a spec for that, they will say that it should take between 1,653-3,858 lbs to press the pin in. I know it has to be around .001 with a max of .002 or so though.

 

[the_skin_eater]

Ya. I can keep em in that tolerance...Its just easier with certain machines, which obviously requires more time.

I figure as long as the hole is straight, it shouldnt matter toooooo much. Keep it a tight press fit and it should all be good?


If anyone know a lil more that would be great.


Thanks.

---Oh yea. People who get this done...Dont you just take it to a shop and tell em to open it to 22? They dont know what tolerance is on it....So if thats the case it really shouldnt matter, cause no one would be watching for that. Theyd just ream and go......
This is why I am curious. I know its a crucial fit, but how crucial? How carefull are most the shops out there without being told it has to be a near perfect squeeze?
They see 22mm, they make 22, but I bet the tolerance around that varies a bit.

 

[Elvenhome21]

a press fit is normally .001 under, you can go up to .0025 under but then you have to freeze the pins in liquid nitrogen.

 

[JacksonAuto]

For press pins it's .001-.0015".

 

[the_skin_eater]

Ya. I got em made to approx. .001.

Thanks for the info. guys.