How hot and how long before melt down?
12-29-2007, 05:22 PM
#16
Guys, the aluminum piston will melt at 1275*. how long does it take to get the top of the piston to 1275 is your guess!!
Also you need to understand the pyro may be off be 100*, so is it on the high side or low side?
most trucks can go 20 seconds with the pyro at 1400-1600 degrees.
Also you need to understand the pyro may be off be 100*, so is it on the high side or low side?
most trucks can go 20 seconds with the pyro at 1400-1600 degrees.
12-29-2007, 06:00 PM
#17
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yes I was but, the melted piston TST tune was only if you went over 2/2 which I never did. Also, the TST worked on some trucks and not others. My truck was one that it worked on and I ran it for 6 months before the melted down. That just happen from getting too happy at the track 
12-30-2007, 08:51 AM
#18
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Guys, the aluminum piston will melt at 1275*. how long does it take to get the top of the piston to 1275 is your guess!!
Also you need to understand the pyro may be off be 100*, so is it on the high side or low side?
most trucks can go 20 seconds with the pyro at 1400-1600 degrees.
Also you need to understand the pyro may be off be 100*, so is it on the high side or low side?
most trucks can go 20 seconds with the pyro at 1400-1600 degrees.
12-30-2007, 10:28 AM
#19
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Cummins swears up and down you cant hurt a stock motor in the Ram chassis... cant over EGT's and cant overfuel... well IMO 1400* while towing is way too hot. Yes there are piston coolers, and thats only on 1/4 strokes... but still too hot... So instead of really worrying about it, and driving the EGT's I put a smarty Jr on 40hp... slightly advanced timing and she dont cook anymore.
12-30-2007, 10:36 AM
#20
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Guys, the aluminum piston will melt at 1275*. how long does it take to get the top of the piston to 1275 is your guess!!
Also you need to understand the pyro may be off be 100*, so is it on the high side or low side?
most trucks can go 20 seconds with the pyro at 1400-1600 degrees.
Also you need to understand the pyro may be off be 100*, so is it on the high side or low side?
most trucks can go 20 seconds with the pyro at 1400-1600 degrees.
Thankfully... or we'd all be up a creek w/o a paddle...
12-30-2007, 11:33 AM
#22
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12-30-2007, 12:51 PM
#23
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My pistons took 1700 degrees for alot of 1/4 miles....the rings in one piston finally cracked into 5 pieces on found their way between the two turbos... The whole deal is time over temperature. If you are towing and maintaining the block near heat sink then 1250 is the max with a max of 1350 on a hill. anything more will melt the pistons. If you are just dynoing then EGT's probably don't matter. If you are drag racing and sledpulling you can hold 1400 to 1550....but eventually you will cause a failure. At 1700 degrees you have a problem that only better cooling and better airflow will solve. In my case I needed a better intake, better intercooler and bigger top turbo.
Higher timing will reduce EGT's but it may actually cause higher piston and cylinder temperatures. You will see your coolant temps spike higher with more timing. In my mind very few people have solved the cooling problems of running our trucks consistently over 600hp. Twins help but they are just a part of the solution. KS
Higher timing will reduce EGT's but it may actually cause higher piston and cylinder temperatures. You will see your coolant temps spike higher with more timing. In my mind very few people have solved the cooling problems of running our trucks consistently over 600hp. Twins help but they are just a part of the solution. KS
12-30-2007, 01:46 PM
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My pistons took 1700 degrees for alot of 1/4 miles....the rings in one piston finally cracked into 5 pieces on found their way between the two turbos... The whole deal is time over temperature. If you are towing and maintaining the block near heat sink then 1250 is the max with a max of 1350 on a hill. anything more will melt the pistons. If you are just dynoing then EGT's probably don't matter. If you are drag racing and sledpulling you can hold 1400 to 1550....but eventually you will cause a failure. At 1700 degrees you have a problem that only better cooling and better airflow will solve. In my case I needed a better intake, better intercooler and bigger top turbo.
Higher timing will reduce EGT's but it may actually cause higher piston and cylinder temperatures. You will see your coolant temps spike higher with more timing. In my mind very few people have solved the cooling problems of running our trucks consistently over 600hp. Twins help but they are just a part of the solution. KS
Higher timing will reduce EGT's but it may actually cause higher piston and cylinder temperatures. You will see your coolant temps spike higher with more timing. In my mind very few people have solved the cooling problems of running our trucks consistently over 600hp. Twins help but they are just a part of the solution. KS
12-30-2007, 01:54 PM
#25
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the piston displayed on the forum was way over fueled and burnt down from the top first....we have run 1800 for a short period and not had those serious of issues.....trust me we have melted down more than our share of pistons...if the EGT goes up and you get out of it right away you won't see those kinds of melt downs.
12-30-2007, 03:11 PM
#26
The Piers Scale is still the best reference to what is safe EGT's:
1200-1250 - All day
1300-1500 - 3 minutes out of 5
1500-1800 - 1 minute out of 5
1800+ - 30 seconds to Chernobyl
This is fuel only. Starting adding water and/or meth and it does NOT apply. You can and will melt a piston at 1200 degrees.
1200-1250 - All day
1300-1500 - 3 minutes out of 5
1500-1800 - 1 minute out of 5
1800+ - 30 seconds to Chernobyl
This is fuel only. Starting adding water and/or meth and it does NOT apply. You can and will melt a piston at 1200 degrees.
01-02-2008, 10:46 AM
#27
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Come on...push it a little harder!
The worst couple of hauls for me were 1000 miles each at 1400 to 1450 degrees for me continuous! LOL.
My pistons/head looke dlik ea spring chicken at 100k...lol.
The worst couple of hauls for me were 1000 miles each at 1400 to 1450 degrees for me continuous! LOL.
My pistons/head looke dlik ea spring chicken at 100k...lol.
01-02-2008, 01:40 PM
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This doesn't really matter. We are reading exhaust temps with our probes/guages. The physics of heat retention (or something of the like) show that while the exhaust gasses may be 1400degrees, the surfaces surrounding this gas will only be 800 degrees. These numbers are just examples. You have to remember, the piston and cylinder remove heat into the water jackets, etc. The pistons are oil cooled, so a lot of that heat is transfered to the oil.
Thankfully... or we'd all be up a creek w/o a paddle...
Thankfully... or we'd all be up a creek w/o a paddle...
AGREED!!!!!
All of this discussion will give you an idea of what temp your motor may/may not melt at this time but give it 5K more miles and then what?????
EGT readings are best used as tuning #'s, the reason most programmers recomend or come with an EGT probe to monitor!!!!!!!
99% of the time when you burn down your motor you will never see the spike in EGT's because it happens so fast.
Thats right just give her a lil' more fuel and a tad more timing it wont hurt, not just this time!!
01-02-2008, 04:23 PM
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01-03-2008, 06:58 PM
#30
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Best reference.
The Piers Scale is still the best reference to what is safe EGT's:
1200-1250 - All day
1300-1500 - 3 minutes out of 5
1500-1800 - 1 minute out of 5
1800+ - 30 seconds to Chernobyl
This is fuel only. Starting adding water and/or meth and it does NOT apply. You can and will melt a piston at 1200 degrees.
1200-1250 - All day
1300-1500 - 3 minutes out of 5
1500-1800 - 1 minute out of 5
1800+ - 30 seconds to Chernobyl
This is fuel only. Starting adding water and/or meth and it does NOT apply. You can and will melt a piston at 1200 degrees.