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I would tighten the top ring to .018". Other than that, should be fine. Have fun getting a machine shop to go really easy on those cylinders LOL. Mine always complains when I come in only wanting just a smidge taken off..
You can remove as much material as you want with a hone. I've watched people hone blocks .020" over because the boring machine was being serviced. It just comes down to what stones are being used. Rough stones cut faster than finer stones and finer stones leave a better crosshatch finish.
Your desired ring end gaps look just fine for your goals. Same for PTW. Keep in mind that while measuring, your actual piston size is always the largest number you obtain out of all the times you measure it. For the bore it'd be the smallest number you see. Even if the piston or bore isn't perfectly round those are the numbers you would use since that would dictate the tightest possible clearance.
Definitely find a shop that has a torque plate, but more importantly also has diamond stones for their cylinder hone. With diamond stones they can plateau hone the cylinder walls and that will result in not only a much shorter break in period but also a much more consistent break in.
Thanks ayoustin, I will definitely keep that in mind. I'll remeasure a couple more times before going to the machine shop to be sure these are the numbers I have. Sometimes I feel like getting the exact low, center, of the piston skirt is a pain, especially since the micrometer ends like to slip around on the piston body before thimble torque is applied.
Originally Posted by letsgetthisdone
I would tighten the top ring to .018". Other than that, should be fine. Have fun getting a machine shop to go really easy on those cylinders LOL. Mine always complains when I come in only wanting just a smidge taken off..
That sounds like a plan! I actually prefer a tighter top ring as well, but wasn't too sure how tight I could run it.
I called a local machine shop who has worked with 4g63 before and they have a torque plate. They said it would be $230.00 for Hone with torque plate and hot tank. Then $145.00 to clean, pressure test, and resurface the head. Hopefully those numbers sound ok. These guys are 6 minutes from my house which is great.
Anyone here know of any bad experiences with "Quality Auto Machine" in San Diego?
When he bolts on a tq plate, all the cylinders will go out of round by a signifficant margin..
That's a good question and since the torque plate is designed to simulate the forces imposed on the block by the cylinder head, any extreme out of roundness could potentially reveal another way I was burning so much oil.
Did more work last night. Took the cam assemblies, rockers, and lifters out of the cylinder head and cleaned with denatured alcohol. After that I removed the main studs, crank, and main bearings. Oil squirters came out last.
Now for some final prep work before I drop everything off at the machine shop tomorrow.
The block will be honed so that the PTW is 0.0050, then hot tanked. They will have my pistons to make sure they don't go over (hopefully)
The cylinder head will be cleaned, pressure tested, and resurfaced. If it all works out, i'll be ordering a new set of piston rings and starting the reassembly.
Well Gents, the block, pistons(for reference) and cylinder head have been dropped off at the local machine shop. The block will be honed to 0.0050" PTW with a torque plate and then hot tanked. The cylinder head will be cleaned, pressure tested, and resurfaced. Any remaining damage after the resurface on the cylinder head side in cylinder 4, i'm going to clean up later with rotary tools.
I did have a chance to check the top and bottom compression ring gaps. The numbers are all ball park, but not consistent. I will be checking oil clearances once I reassemble the block as I will be reusing all the bearings. They all showed minimal wear and usage.
Ring Gaps
Cylinder 1
Top : 0.018"
Bottom: 0.022"
Cylinder 2
Top : 0.019"
Bottom: 0.022"
Cylinder 3
Top : 0.019"
Bottom: 0.024"
Cylinder 4
Top : 0.020"
Bottom: 0.024"
Sadly, after taking apart the entire block and scrutinizing the hell out of it, there is no clear culprit as to why my engine was burning so much oil. My best assessment is that it was a combination of fuel washing down cylinders earlier in the break in process, which did not let the rings seat properly or it was the oil rings on each piston which may not have been clocked properly. Even then so, I've never heard of rings being clocked poorly resulting in this much oil burning.
It's time to move on.
Once I get the block and cylinder head come back from the machine shop, i'll be purchasing a new set of rings and potentially replacing the valve stem seals again. I did a water test on the cylinder head bowls and nothing is leaking past the valves when they are shut. Valve seats must be in decent shape.
Your tune would have had to have been SUPER rich to wash the cylinders of oil, like, single digit AFR's rich.
Oil burning could be as simple as an improper hone, the uneven ring gaps point to that (assuming they were gapped the same across all four cylinder on install). At this point, as long as she runs good when it goes back together, who really cares. You're definitely taking all the steps to make it run well.
Your tune would have had to have been SUPER rich to wash the cylinders of oil, like, single digit AFR's rich.
Oil burning could be as simple as an improper hone, the uneven ring gaps point to that (assuming they were gapped the same across all four cylinder on install). At this point, as long as she runs good when it goes back together, who really cares. You're definitely taking all the steps to make it run well.
Thanks man, I really hope she does. I want to be able to drive it to Vegas one day without any issues at all. I like to think of this car like an expensive essay. You have your first draft and then revise, revise, and improve some more.
Machine shop just called and said that the cylinder head passed the pressure test and is cleaned and resurfaced. The block was honed 0.001" over and hot tanked. All parts were cleaned up and i'm picking up tomorrow morning.
I just ordered 4 sets of Wiseco 85.5mm piston rings. Let's see if I can't put her back together better than she came apart. I'm back and forth about replacing my valve stem seals again. They have less than 1000 miles on them. Could they be damaged in the hot tanking procedure?
Valve stem seals are taken off before hot tanking, if they were left in they would retain moisture which could cause all sorts of issues for the valves. With that said, a set of seals from GSC that uses higher temp rated viton than stock is only $15 so I think it's good piece of mind to just replace them.
Also, be sure to get a ring file to set the end gaps on the rings properly.