Opinions Thoughts Quesses

[Bulldogger]

Running a Performance/Tow tune from Kennedy Diesel, 370/725 to the wheels which is about 450/900 at the crank assuming a 20% drive train loss. Truck is used for towing a heavy 5'ver. Combine weight of 25,000-26,000. Will it break a piston?

[BudTX]

I certainly don't have the answers, nor do I have firsthand experience, but I have heard several folks talk that heat is what is causing cracked pistons. I would worry about EGTs. What are you seeing when pulling hard with that tune?

[Bulldogger]

Running real hard 1375 tops, usually 1200-1350 is normal, and mostly due to the fact that the six speed likes to hold 6th, when it drops to 5th usually 1250-1275 running 68 through the hills of I-80 in Pa. The Kennedy tune runs lower EGT's then factory stock.

[blksmok]

The jury is still out on what is causing the pistons to crack. We may never know for sure, but there is an excellent thoughts and discoveries discussion going on here. Take a look.

http://dmaxcentral.com/forum/showthread.php?t=44

[Bulldogger]

I read through that and every other post I could find, It's like watching my dog chase his tail, I get a headache and still don't have any clearer insight as to what just happened or what the end result was):h.
Leaving the end of June to Michigan for wrestling camp for my son. Then to Kentucky, then Fla. Wondering in the back of my mind if I'll be one of the LUCKY ones.

[hondarider552]

personally, i drive based on egt. i also pull near stock (+40ppe) so its not too bad of an issue. it wont break a piston, it will crack it ):h

[blksmok]

personally, i drive based on egt. i also pull near stock (+40ppe) so its not too bad of an issue. it wont break a piston, it will crack it ):h

:lying: How about when you forgot to switch your PPE tune back and you were towing with the 425 loaded was it? ):h How high were your EGT's again? :D

[carhauler]

I constantly go over 1400 with the preditor on the 45 HP tow tune pulling long hills loaded I have gone back to stock and done the same thing ,I try and get out of it but sometimes with the cruise on I forget. I have got alot of miles and (knock on wood) all is well ,I think if I don't decide on a new one soon I will go with the kennedy custom tune,Heard nothing but GOOD about it . I ran the 85 horse towing this winter and it actually ran cooler EGT's until the weather got hotter .... got better milage too.

[RickDLance]

And I've seen stock trucks crack a piston. I saw a phone company truck at one of the local dealers. Showed all the "normal" signs of power adders.

That must have been the fastest telephone pole setting truck in the country!):h

[duratothemax]

Running a Performance/Tow tune from Kennedy Diesel, 370/725 to the wheels which is about 450/900 at the crank assuming a 20% drive train loss. Truck is used for towing a heavy 5'ver. Combine weight of 25,000-26,000. Will it break a piston?

thats a 2 million dollar question you just asked...

[Bulldogger]

thats a 2 million dollar question you just asked...

Actually it is about a 12,000 dollar bill at Merchant's):h