[JimGnitecki]

Originally Posted by WiggyB

. . .
Big thanks to everyone though you make a person really do their research and make the proper decisions on which route would be best for them.

Knowledge is power.......................

Agree!

Jim G

[L78toLT1]

Originally Posted by Kerry

Once again I fail to comprehend how a piston ring can expand 10 thousands or more to close the ring gap but not expand the width 10 thousands and lock up in the ring land. I know everyone says that. Even engineer's at Wesco recommended 35 thou to me on the last build.

How can it grow length wise but no other way. Clearance on a ring land s like 2 thou maybe at most. Last I checked when u heat metal it grows all directions not just one.

Metal expansion is expressed in inches per inch. The rings are a little over 12 inches long (pi x 4.06). Thickness is probably. 060 - .080, so no where near the same amount of expansion

[Kerry]

[QUOTE=L78toLT1;11256177]Metal expansion is expressed in inches per inch. The rings are a little over 12 inches long (pi x 4.06). Thickness is probably. 060 - .080, so no where near the same amount of expansion[/QUO

Help me out here/ Not being a smart as I really dont know. So are you saying that a ring could grow 11 thousands in length but not 2 thousands in width at the same heat?

[JimGnitecki]

[QUOTE=Kerry;11256243]

Originally Posted by L78toLT1

Metal expansion is expressed in inches per inch. The rings are a little over 12 inches long (pi x 4.06). Thickness is probably. 060 - .080, so no where near the same amount of expansion[/QUO

Help me out here/ Not being a smart as I really dont know. So are you saying that a ring could grow 11 thousands in length but not 2 thousands in width at the same heat?

IF all the above is true, then t's basic math:

The piston ring's total circumference is about 12 inches. It's thickness though, apaprently, is only say .07 inch.

So the thickness is 0.07/12 = .00583 of the circumference.

Too seize up, the ring apparently has to grow by only .010".

That .010" is only 0.010 / 12 = .000833 of the circumference.

If the thickness expands to the same proportion as the circumference (there's an "if" here), then the thickness will expand from .010" to .010" x (1 + .000833) = .01000833". That's a gain in thickness of only (.01000833 - .010) = .00000833" or about .00833 of one thosuandth of an inch. Not enough to seize it.

Jim G

[Kerry]

[QUOTE=JimGnitecki;11256244]

Originally Posted by Kerry

IF all the above is true, then t's basic math:

The piston ring's total circumference is about 12 inches. It's thickness though, apaprently, is only say .07 inch.

So the thickness is 0.07/12 = .00583 of the circumference.

Too seize up, the ring apparently has to grow by only .010".

That .010" is only 0.010 / 12 = .000833 of the circumference.

If the thickness expands to the same proportion as the circumference (there's an "if" here), then the thickness will expand from .010" to .010" x (1 + .000833) = .01000833". That's a gain in thickness of only (.01000833 - .010) = .00000833" of about .00833 of one thosuandth of an inch. Not enough to seize it.

Jim G

Kool thanks

[L78toLT1]

[QUOTE=JimGnitecki;11256244][QUOTE=Kerry;11256243]

IF all the above is true, then t's basic math:

It's true, and your math is correct. The amount that metals expand with heat is directly related to the length of the material.

[Kerry]

non the less ring gap for a zl1 according to all data is the same as the lt1 at 11 thou. i know their are stock zl1s being pushed to over a 1000 crank with meth ect. No ring gap problems their.

Im not good at math at all. But I do know engines and what things look like when they fail. Cant always tell what happened first, but if a ring butts enough to break a piston then its gonna show up on the cylinder wall.

It was a week end and a bunch wanted to ride so I put a ring in a motor that was made for the next size up piston. (I was in a pinch) got the correct gap of 11 i think it was may be 15. It ran but just that .5mill over size even though it was proper gap streaked up the cylinder wall.

I think it would be hard for for the ring butt to be exact as well like to be perfectly flush on the ends. For it to be tight enough to cause enough drag to bow up enough in the ring land to break a piston would be tight in the cylinder bore. I just dont buy this whole ring gap causes fails lt1 pistons.

I think they are crap pistons and not able to take a lot. also I think its more luck of the draw. Some are just made better than others.

At the end of the day it just dont matter. I just hate to see someone pull down a motor to open the ring gap and put it all back together only to break a ring land any way.

[KingLT1]

Shortly after the 6th gen came out somebody took a LT1 and gapped the rings for boost. It made over 900whp. This was before the drop-in forged stuff came around. Nobody does it because the effort involved doesn't make sense with the drop in offering on the market. There is no reason to mess with it at this point.

I could be wrong, but I am almost positive the LT4 has wider ring gaps (I have seen .025 reported) but even if it didn't, the LT4 definitely has different rings and is also 1.5 points lower in compression which is huge. Revert back to high cylinder temps causing decreased ring gap comment.

The next question ask yourself is: How many SBE failures do you know of that were on E85 vs Pump gas? I am going to say 100:1 ratio pump vs E is a safe bet.

[Joshinator99]

Originally Posted by KingLT1

Shortly after the 6th gen came out somebody took a LT1 and gapped the rings for boost. It made over 900whp. This was before the drop-in forged stuff came around. Nobody does it because the effort involved doesn't make sense with the drop in offering on the market. There is no reason to mess with it at this point.

I could be wrong, but I am almost positive the LT4 has wider ring gaps (I have seen .025 reported) but even if it didn't, the LT4 definitely has different rings and is also 1.5 points lower in compression which is huge. Revert back to high cylinder temps causing decreased ring gap comment.

The next question ask yourself is: How many SBE failures do you know of that were on E85 vs Pump gas? I am going to say 100:1 ratio pump vs E is a safe bet.

Hard to say what’s killed more SBE LT1s, pump gas or pump gas with meth. I’m going to bet on pump w/meth because the meth seduced owners into thinking that lower IATs would allow them to turn up the boost but save their SBE . Spoiler alert: it didn’t.

I can personally say (and so can King!) that you can definitely play around up near 700 WHP on the SBE with a high E concentration. I had some data logs that horrified the crap out of me after I did a run and pushed things too far…yet the SBE continued to live thanks to running E. Only did drop ins because I was planning on going nuclear.

[laynlo15]

Originally Posted by KingLT1

Shortly after the 6th gen came out somebody took a LT1 and gapped the rings for boost. It made over 900whp. This was before the drop-in forged stuff came around. Nobody does it because the effort involved doesn't make sense with the drop in offering on the market. There is no reason to mess with it at this point.

I could be wrong, but I am almost positive the LT4 has wider ring gaps (I have seen .025 reported) but even if it didn't, the LT4 definitely has different rings and is also 1.5 points lower in compression which is huge. Revert back to high cylinder temps causing decreased ring gap comment.

The next question ask yourself is: How many SBE failures do you know of that were on E85 vs Pump gas? I am going to say 100:1 ratio pump vs E is a safe bet.

I think Sean from Speed Engineering did that, I know he did on his Zl1 and Z06 because I talked to him about that at Sema, but thinking he also did an Lt1 early on.

[laynlo15]

Originally Posted by Joshinator99

Hard to say what’s killed more SBE LT1s, pump gas or pump gas with meth. I’m going to bet on pump w/meth because the meth seduced owners into thinking that lower IATs would allow them to turn up the boost but save their SBE . Spoiler alert: it didn’t.

I can personally say (and so can’t King!) that you can definitely play around up near 700 WHP on the SBE with a high E concentration. I had some data logs that horrified the crap out of me after I did a run and pushed things too far…yet the SBE continued to live thanks to running E. Only did drop ins because I was planning on going nuclear.

Well we know mine is at 707 pretty safely on fairly low boost. We don't plan on going any higher on Boost or HP.

[Kerry]

Originally Posted by laynlo15

Well we know mine is at 707 pretty safely on fairly low boost. We don't plan on going any higher on Boost or HP.

So if 707 wheel them that's about 790 or so crank then it has to turn the blower so that's a good 60 minum probly like 80. Now what's ur crank power. So yes I would say around 700 is max safe ish on sbe.

I was about 1000 crank and bent stock rod and broke 2

[Joshinator99]

Originally Posted by laynlo15

Well we know mine is at 707 pretty safely on fairly low boost. We don't plan on going any higher on Boost or HP.

Yeah, you’re on a high volume of E with knowledgeable tuners. I’d say your in great shape. I mean, you could still launch parts…but you’re in better position than most who make that much power on SBE. In my humble opinion, of course.

[Joshinator99]

Originally Posted by Kerry

I was about 1000 crank and bent stock rod and broke 2

You were definitely asking for it.