Sometimes when I get bored........I build another car
05-30-2012, 08:51 AM
#41
Le Mans Master
Did you have a rear coolant crossover tube on the back to let the super heated coolant return back to the radiator? I hear this causes hot spots in the cylinder liner on # 5 & 7. Once I rip my driveline out for the 6060 swap Im going to redo my fuel system and also do this mod.
There are a couple kits out on the market to do it...they are expensive but at this point in the game, may as well do it.
05-30-2012, 08:56 AM
#42
Le Mans Master
When adding a turbo, blower or spray, one usually opens up the top ring gap so it doesn't close up, butt together and break the ring land.
Do you know if that was done on this engine Alan?
To add coolant to the back on an LS6 you can add a front coolant crossover turned around. The hose plumbing might be a bit tricky, but I'm working on that.
Ron
Do you know if that was done on this engine Alan?
To add coolant to the back on an LS6 you can add a front coolant crossover turned around. The hose plumbing might be a bit tricky, but I'm working on that.
Ron
05-30-2012, 11:45 AM
#43
Melting Slicks
Hey Ron, the original engine had never been opened up so the gaps were definitely not adjusted. What gets me is, if this problem is as simple as ring gaps closing up and lifting lands, why is it almost always the 5/7 cyls in LS motors that bite the dust? It is possible that was the problem here but.... I have my doubts. I'd buy the poor cooling for 5/7 theory first I think.
05-30-2012, 02:59 PM
#44
Safety Car
Hey Ron, the original engine had never been opened up so the gaps were definitely not adjusted. What gets me is, if this problem is as simple as ring gaps closing up and lifting lands, why is it almost always the 5/7 cyls in LS motors that bite the dust? It is possible that was the problem here but.... I have my doubts. I'd buy the poor cooling for 5/7 theory first I think.
Those pictures aren't from the top ring butting, and lifting the top ring land. They're pictures of what mild detonation does. I've seen that in engines going back to the LT1 days. It's hard to make a lot of boost and a lot of power on a stock bottom end, without that happening. Gotta walk that fine line. Too much timing will do that.
So Ed, mild detonation would happen in those 2 cylinders if they ran somewhat hotter, correct? A buddy literally melted those 2 pistons in his forged setup.
Ron
05-30-2012, 04:00 PM
#45
Melting Slicks
I'll take a photo of the front crossover on the rear. I haven't slid the manifold on with it yet though. I'm not sure why the LS-1 part wouldn't work. It connected all 4 ports. But then I don't know what the LS-6 valley cover looks like either. I know the LS-1 part will fit under the LS-6 intake with some work. It will not fit under a FAST for sure.
So Ed, mild detonation would happen in those 2 cylinders if they ran somewhat hotter, correct? A buddy literally melted those 2 pistons in his forged setup.
Ron
So Ed, mild detonation would happen in those 2 cylinders if they ran somewhat hotter, correct? A buddy literally melted those 2 pistons in his forged setup.
Ron
To melt forged pistons, that's definitely tuneup related. You've got to be making a lot of combustion heat to melt a forged piston. Could be an injector failure too, but that is less likely.
Remember, in these engines, we don't have individual cylinder fueling control. Compound that with only using 1 wideband, which ends up averaging 4 cylinders at the very minimum, and you run the risk of running at least one cylinder lean, even if the wideband reads good. This is the "roll of the dice" when trying to tune aggressively.
05-30-2012, 04:52 PM
#46
Le Mans Master
Member Since: Jul 2005
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St. Jude Donor '08
After reading some pretty good stuff from Kurt Urban about the rear crossover and some coolant hot-spots, I decided to add the rear crossover in my latest engine build. It's been great so far and It wasn't expensive. I could have made it as expensive as I wanted, but for something so simple, I decided on a method that was efficient and fit my needs.
05-30-2012, 11:39 PM
#47
Melting Slicks
First of all nice build thread I am anxious to read about how this comes out.
I dont wanna highjack the thread but can you or someone post more information on this here or start a thread with info. on this I have never heard of this.
After reading some pretty good stuff from Kurt Urban about the rear crossover and some coolant hot-spots, I decided to add the rear crossover in my latest engine build. It's been great so far and It wasn't expensive. I could have made it as expensive as I wanted, but for something so simple, I decided on a method that was efficient and fit my needs.
05-31-2012, 01:55 AM
#48
Safety Car
Yeah, they do run hotter. I'm not sure if it's the cooling system, or an air distribution problem, or a little of both.
To melt forged pistons, that's definitely tuneup related. You've got to be making a lot of combustion heat to melt a forged piston. Could be an injector failure too, but that is less likely.
Remember, in these engines, we don't have individual cylinder fueling control. Compound that with only using 1 wideband, which ends up averaging 4 cylinders at the very minimum, and you run the risk of running at least one cylinder lean, even if the wideband reads good. This is the "roll of the dice" when trying to tune aggressively.
To melt forged pistons, that's definitely tuneup related. You've got to be making a lot of combustion heat to melt a forged piston. Could be an injector failure too, but that is less likely.
Remember, in these engines, we don't have individual cylinder fueling control. Compound that with only using 1 wideband, which ends up averaging 4 cylinders at the very minimum, and you run the risk of running at least one cylinder lean, even if the wideband reads good. This is the "roll of the dice" when trying to tune aggressively.
Back to the build!
05-31-2012, 02:22 PM
#49
Drifting
Member Since: Sep 2008
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After reading some pretty good stuff from Kurt Urban about the rear crossover and some coolant hot-spots, I decided to add the rear crossover in my latest engine build. It's been great so far and It wasn't expensive. I could have made it as expensive as I wanted, but for something so simple, I decided on a method that was efficient and fit my needs.
05-31-2012, 09:52 PM
#50
Le Mans Master
Coolant Cross-Over lines
These are old pics on a my mock up engine, since then I tied the front lines together also.
The highest point is the overflow tank which allows air, steam & water to escape the top of the heads without an air pocket.
I also have a 3/8 line (not shown) from the over flow fill neck to the rear of the car, in case the coolant system pressurizes.
The highest point is the overflow tank which allows air, steam & water to escape the top of the heads without an air pocket.
I also have a 3/8 line (not shown) from the over flow fill neck to the rear of the car, in case the coolant system pressurizes.
05-31-2012, 10:14 PM
#51
Melting Slicks
JM I'm looking into the cross over as well. I talked to the engine builder about it and he was not that concerned about doing it... He was going to research it as well.
There are a couple kits out on the market to do it...they are expensive but at this point in the game, may as well do it.
There are a couple kits out on the market to do it...they are expensive but at this point in the game, may as well do it.
05-31-2012, 10:48 PM
#52
Le Mans Master
I may try to get one from Kurt Urban if I can get them to make me one with black lines/fittings. At $200 I would spend more trying to build my own. I'm not crazy about how he mounts the 4:1 box on top of the stock intake though.
I'm still kicking this around...hopefully it's worth the effort/expense. I see many trains of thought on this subject. Most don't mess with it though. I'll do anything to help prevent another piston melt down
I'm still kicking this around...hopefully it's worth the effort/expense. I see many trains of thought on this subject. Most don't mess with it though. I'll do anything to help prevent another piston melt down
Your posting late. Another long day at work buddy?
06-01-2012, 08:44 AM
#56
Safety Car
These are old pics on a my mock up engine, since then I tied the front lines together also.
The highest point is the overflow tank which allows air, steam & water to escape the top of the heads without an air pocket.
I also have a 3/8 line (not shown) from the over flow fill neck to the rear of the car, in case the coolant system pressurizes.
The highest point is the overflow tank which allows air, steam & water to escape the top of the heads without an air pocket.
I also have a 3/8 line (not shown) from the over flow fill neck to the rear of the car, in case the coolant system pressurizes.
06-01-2012, 11:19 AM
#57
Le Mans Master
New Dewitts radiator (Thanks Arun), what a work of art this thing is....
Beginning stages of modding my stock fan shroud to properly seal up to the new cut down radiator..
Bret and I decided to build our own 4 corner coolant cross over using some of Urban's stuff... Just something else to add to the list of crap to do...
Beginning stages of modding my stock fan shroud to properly seal up to the new cut down radiator..
Bret and I decided to build our own 4 corner coolant cross over using some of Urban's stuff... Just something else to add to the list of crap to do...
06-01-2012, 12:40 PM
#58
Safety Car
New Dewitts radiator (Thanks Arun), what a work of art this thing is....
Beginning stages of modding my stock fan shroud to properly seal up to the new cut down radiator..
Bret and I decided to build our own 4 corner coolant cross over using some of Urban's stuff... Just something else to add to the list of crap to do...
Beginning stages of modding my stock fan shroud to properly seal up to the new cut down radiator..
Bret and I decided to build our own 4 corner coolant cross over using some of Urban's stuff... Just something else to add to the list of crap to do...
06-01-2012, 12:58 PM
#59
Le Mans Master
Yes it's bondo. I'm just building up the notched area (fan clearance) to match a little closer to the top of the factory shroud. Purely for cosmetics.. You'll see..
Ofcourse I'm no metal worker or body guy so....it won't be anything special.
Ofcourse I'm no metal worker or body guy so....it won't be anything special.
