What are the clearances I tell the specialist that is honing my block? I have stock pistons that I will be using, I just want it honed so the new rings will seat right. I don't have a FSM, and I can't find my Hanes manual either. I searched but I really want to hear it a couple of times before I have it done. I need to know soon the the guys can get to work on it tomorrow.

The cylinder walls were in very good condition btw, and I only wish to remove the glaze that the old rings leave.

Piston to bore clearance is (.01-.03mm)

Cylinder bore diameter grade 1= 86.000-86.010mm
2=86.010-86.020mm
3=86.020-86.030mm

Piston skirt diameter grade 1= 85.980-85.990mm
2= 85.990-86.000mm
3=86.000-86.010mm

Hope this helps.
Mike

Thanks man, just what I needed!

Okay wtf, the guy at the shop is saying my cylinder's are smaller by 1-2 thousandths than the dimensions you gave me Mike. What do I tell him?

the final bore/hone will depend on the grade of piston you have. the piston should be stamped with a number on the top. My guess you have oversize pistons if there is that much difference

over size piston
86.180 - 86.210 (3.3929" - 3.3941)

Okay wtf, the guy at the shop is saying my cylinder's are smaller by 1-2 thousandths than the dimensions you gave me Mike. What do I tell him?

hmm.. What is he measuring it with? What pistons grades are you using/do they match the grade on the top of the block? According to my measurements my block and pistons are within .0005. I used a T gauge and a digital vernier. I'm still waiting to get the anvil extensions for my bore gauge to double check.

Mike

The pistons came out of that black, I don't know all of those technical terms yet. I will have my friend look at it. The guy is measuring with standard.

Interesting. They should be the correct size then. Is it possible the guy at the shop is measuring the wrong piston for the wrong bore?

As Pat said the pistons are marked with the grade on the top of them. And like wise the block is marked with the bore grade on the top of the cylinder. The grade mark looks like this on the piston: (this is a grade 2 piston btw)
http://www.sr20.net/d/63986-2/IMG_1362.JPG
And here you can see the grade marking on the block: (also grade 2 upper middle of the picture)
http://www.sr20.net/d/63203-2/P4280125.JPG

Now allot of motors have different grading for each cylinder so.. If your guy is measuring the wrong piston for the wrong bore it will look like it’s grossly out of spec. Although .002 is allot to be out of spec. I think the limit is @ .0007ish. Or.. the guy could just be measuring wrong.. I dono..

Mike

Save these and print them out if you need them:

http://www.sr20.net/d/65485-1/em-63.jpg

http://www.sr20.net/d/65488-1/em-64.jpg

Mike

Lol well maybe I should take him the pistons then? He doesn't have them btw.

I will take them to him on monday since I have that day off....

I will update, and thanks for those pics!

yeah, your shop should have the pistons in hand to measure for each bore.....so now you know ;)

Okay lol, my engine guru is out of town, so how do I take the pistons off the rods?

Edit: looked at the pistons, how do I remove the carbon build up?

Also do my conversions look okay? The guy wanted them in standard sizes....

Cylinder Bore Diameters:

Grade 1= 86.000-86.010mm (or 3.3858-3.3862 in.)
Grade 2= 86.010-86.020mm (or 3.3862-3.3866 in.)
Grade 3= 86.020-86.030mm (or 3.3866-3.3870 in.)

Piston Skirt Diameters:

Grade 1= 85.980-85.990mm (or 3.3850-3.3854 in.)
Grade 2= 85.990-86.000mm (or 3.3854-3.3858 in.)
Grade 3= 86.000-86.010mm (or 3.3858-3.3862 in.)

My pistons were dirty also. I couldn’t get the ring lands clean enough for my liking. I had the shop doing my work clean them up by bead blasting them with a soft media made for cleaning aluminum and casting material. I guess it only cleans the surface without removing any of the material underneath. It cost me @ $10/ piston.

I had them clean the head the same way but that is another story.. Do not have this done unless you feel like popping out all the galley plugs and getting the head recleaned after :(

Your conversions look ok to me. You can print out the pages I posted above if you like. I pulled them rite out of the fsm.

Mike

p.s. you need a piston pin press to take them off the rods. Or you can heat them up to 165 deg F and slide the pins out. I used an arbor press with a little jig (a 2" thick walled pipe and a piece of fat drill stock..) that allowed the pin to be pressed out.

Mike

Okay well I think I will just take them the pistons with the rods, they are not the rods I will be using anyways (got some new ones cryotreated).

I will ask them if they can clean them up so I can read them. Thanks for your help!

You could soak the pistons in carb cleaner for a day or so, most of the carbon would come off quite easily after that.

Mike

OKAY WTF! I just took them the pistons and the specs I posted above and the bore is 1-2 thousandths SMALLER than the lowest grade 1 specs! To top that off, the pistons are bigger than the highest grade 3 specs, and THE PISTONS FIT INTO THE BLOCK!

I don't know what to do, this shit is way to confusing.

Mike, is there anyway you can get a bigger picture of the cylinder specs and piston specs from the FSM? I can't read those pictures.

I can try to clean them up later when I get home and re-upload them for you.

Only thing I can think of is his measurement process is somehow faulty.?

Mike

They must be measuring wrong, as on paper they have the bore smaller than the pistons.

They do need cleaning before measring though.

Mike

I have rust on the inside of my cylinder walls, how do I clean that off (besides honing)? Scotch brite and some oil? I'm having the pistons cleaned for $10, and the block hot tanked for $50, should I have him measure it again after it's all clean?

I am just going to take the block and pistons to a friends shop and have him look at it (didn't go there in the first place because it is about an hour away).

Thanks for the help Mikes!