[enkeivette]

So Im going to hone this little Honda engine with that 3 stone honing tool. But the stones look too rough for a final finish. Does anyone have an idea what grit cylinder walls are finished with? Im not buying a $50 flex hone to rebuild a $100 engine, ha.

[BRUTAL64]

Originally Posted by enkeivette

So Im going to hone this little Honda engine with that 3 stone honing tool. But the stones look too rough for a final finish. Does anyone have an idea what grit cylinder walls are finished with? Im not buying a $50 flex hone to rebuild a $100 engine, ha.

I use the three stone all the time. They...at least mine, is not too rough. It doesn't take many turns to clean the walls....then after that it starts taking material from the walls...clearances will be a problem.

There are finer stones out there,,but I do not remember the number...getting old I guess.

[enkeivette]

Ok cool, thanks Glenn. I have another question for you, if I have to take off so much material that I need an oversized ring, can I run an oversize ring with a standard piston?

[fiveohwblow]

Originally Posted by enkeivette

Ok cool, thanks Glenn. I have another question for you, if I have to take off so much material that I need an oversized ring, can I run an oversize ring with a standard piston?

I have heard of this being done. More than once. It depends on how much material you take out. Clearly it's not optimal, but within a thousandth or two it's not too bad.

[enkeivette]

You must mean a hundredth or two. I could sneeze a thousandth off the cylinder wall.

Before hone - 2.662, after - 2.672. Thats exactly 1/100. Im going to just run a standard ring, I took more off the Vette motor when I blew up that last piston.

[94cobra69ss396]

That's actually a lot that you took off and will cause the piston to slap around. Are you sure about the measurement? The Probe pistons I run in the Cobra call for a clearance of .003 - .007. I had Dick finish hone the block for .005 because I'm not running an intercooler. That's what I had on with the 302 as well and it didn't have piston slap nor did it scuff the piston skirts even with how hard I ran it.

[enkeivette]

.007 piston clearance is a .014 larger bore. And .03 sounds dangerously tight to me for forged pistons. I've heard of up to .012 clearance/ .022 larger bore.

I'd rather run too much clearance than not enough, without question. I've never heard of a piston rocking itself to death. Same with piston rings, I filed mine to the largest tolerance allowed. Who gives a fuck if it costs me 5hp? I dont want it binding when I push it heat soaked on a hot day.

But anyways... compared to my SBC pistons, this little Honda piston has NO room to breathe. There is no rocking back and forth, in fact with the bit of rust that formed I had to smack the piston out of the hole with a hammer. Hard. So Im not terribly worried. If it was closer to .02/ .03 I would have gone with an oversized piston.

[BRUTAL64]

Originally Posted by enkeivette

Ok cool, thanks Glenn. I have another question for you, if I have to take off so much material that I need an oversized ring, can I run an oversize ring with a standard piston?

You need .004 of ring gap per inch of bore...probably no need to get over size rings....filing rings will cause brain damage.

Most over size rings need to be filed to fit correctly.

You DO NOT want the rings ends to butt when hot---that will rip off the top of the piston

[94cobra69ss396]

Originally Posted by enkeivette

.007 piston clearance is a .014 larger bore. And .03 sounds dangerously tight to me for forged pistons. I've heard of up to .012 clearance/ .022 larger bore.

You and I are talking about two different things. I'm talking about the piston to cylinder wall clearance and you're talking about the piston ring gaps.

Originally Posted by BRUTAL64

You need .004 of ring gap per inch of bore...probably no need to get over size rings....filing rings will cause brain damage.

Most over size rings need to be filed to fit correctly.

You DO NOT want the rings ends to butt when hot---that will rip off the top of the piston

Total Seal rings I bought for the Cobra showed to set the top ring at .0055 x bore, the second ring at .0035 x bore and the oil ring at a minimum of .015 for boosted applications. I set the top rings at .023, the second rings at .016 and the oil rings were .016 out of the box.

The Mahle rings that came with my engine kit were not file fit rings but the end gaps were all over the place. They ranged from .008 up to .016.

[BRUTAL64]

Originally Posted by 94cobra69ss396

You and I are talking about two different things. I'm talking about the piston to cylinder wall clearance and you're talking about the piston ring gaps.



Total Seal rings I bought for the Cobra showed to set the top ring at .0055 x bore, the second ring at .0035 x bore and the oil ring at a minimum of .015 for boosted applications. I set the top rings at .023, the second rings at .016 and the oil rings were .016 out of the box.

The Mahle rings that came with my engine kit were not file fit rings but the end gaps were all over the place. They ranged from .008 up to .016.

Because I used Hypereutectic pistons on my current 400 engine, the end gap had to be big..026....but it works with the hotter Hypereutectic pistons.

The .004 per bore inch is general rule and is different for forced induction and Hypereutectic pistons........