OK guys,

I've been a long time lurker here at the forums but never actually posted so forgive me if I'm in the wrong section.

So I just recently got my b20z2 block machined to 84.5mm because the last owner of the engine disassembled it and left it out in the weather....

So my question is: Knowing that I don't really mean to push any major power with the engine since my girlfriend will more than likely be the one driving it, what type of ring gap should I be at?

Thanks in advance for all the answers.

 

Go purchase a helms manual and rebuild the motor using their factory steps/specs.

Also, searching this forum by using the "search" tab at the top will find you about anything you want to know.

I'll give you a "freebie"

Ring End Gap
Top (new) 0.20-0.35 (Service limit) 0.60
Second (new) 0.40-0.55 (service limit) 0.70

 

I just rebuilt a b20z2 with 84.5mm pistons

I didn't file my rings at all... just checked clearance, and they were :

top : .40 - .50
bottom : .70 - .80 (yes, you read correctly, both above service limit)
P2W = .002"

Not one puff of smoke on start up.. has about 300 miles on it, I beat the living **** out of it, and doesn't puff one bit of smoke. I let it idle for 20 minutes, then red lined it.

One thing people need to understand, a little bit larger gaps won't hurt anything..... what will hurt you is tight ring gaps, which can possibly close when hot = catastrophic damage.

 

The specs I posted are not close or tight be any means. Those specs will not create any issues like butting ring ends, etc.

You sir have just gotten lucky so far

If that were my motor it would smoke like a chimney. That's my luck.

 

think about it.

the difference between .50mm and .75mm, is so damn small. Ive seen tests done, and one motor had a ring gap of .10mm average for both rings, and the other motor had a large gap, of .80mm average for both rings.

after 3500 miles, the oil consumption difference between the two motors was so minimal, it was not a concern at all.

I'm tempted to run large gaps on my turbo motor I'm building shortly.