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Discussion Starter #1
If my upcoming 4bt swap goes well I would like to make some road trips in it. Possibly to Colorado pulling my ATV (trailer 1500-2000 lb). Does anyone see a problem driving in high altitude with this setup? Any precautions I should take? I am about to make a deal on a mid 80s Ford E250 for the engine so I will be using a EPA engine and not a stationary engine.
 

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I believe a turbocharged diesel is effected far less by altitude changes than a gasser engine. Just the fact that it's turbo'd changes the whole picture. Relative air density is a factor, as in aftercoolers etc., but for occasional jaunts up to high altitude probably not a big deal. The semi trucks don't have to pull over and adjust anything or make changes regardless of where they run. Just keep an eye on the pyro and you should be fine.
 

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I'd agree with that too. I don't think there is any altitude compensation on these. I think lack of air will reduce fuel automatically by less combustion in the cyls, so it smokes a little more but I think it auto adjusts a little, so its not too noticeable a change in smoking, unlike a naturally aspirated diesel in altitude. I do notice slight loss of power but not enough that it is a PITA. I've had it as high as probably 12K feet, and I live at about 7-8K feet and it does just fine..
 

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Hmmm... I almost died in a snowstorm over where you live DC! Many years ago, but I won't forget it. Plenty of elevation there.
 

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Discussion Starter #5
Thanks guys, New to the diesel fuel system. My experience is with gas,propane and CNG powered engines. Both with and without computer controlled feedback systems that adjust for altitude. It will be nice to be working with something simpler. Also you answered another question for me, weather or not to run a pyro meter.
 

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I have a 4BT spec sheet at work that mentions how much they should be derated at what altitude.
But that's at work and I've taken a week off.bounce
 

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Something else to consider on that Pyrometer: most of our swap engines are used. Some of the shop diesel mechanics may have wanted to improve performance on a particular stepvan and didn't bother to tell anybody. They could have turned up the screws a bit. You buy the engine thinking it's bone stock and run it hard, towing and pulling grades, figuring you're entirely safe on EGT's [Exhaust Gas Temps]. Uh-oh.....

When I put the Pyro on mine I discovered it can nail a quick 1,200 if I push it, even running empty, here in the mountains. That means when I was towing that same load mentioned elsewhere it could have seen some pretty mean EGT's going on and I had no idea!

Therfore I believe that even 'stock' diesels NEED A PYRO!
 

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Discussion Starter #8
OK, sounds like a deal. Ill get one before I start driving it. Looks like Ill be going to pick up my donor truck this weekend.
 

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Oh the excitement of it all... :)
 

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Pyro for me is totally important. that said I lucked out and my engine, with tons of power and the 120hp 4BTA model, did just fine here and never hit EGTs. But my head gasket started going (common on 4BTs in my opinion -- luckily a very easy & quick job minus the time for machining).. Then, my EGT gauge became crucial and I would have killed my turbo otherwise half way on a 14 hour trip in the middle of Nevada...! A

Something else to consider on that Pyrometer: most of our swap engines are used. Some of the shop diesel mechanics may have wanted to improve performance on a particular stepvan and didn't bother to tell anybody. They could have turned up the screws a bit. You buy the engine thinking it's bone stock and run it hard, towing and pulling grades, figuring you're entirely safe on EGT's [Exhaust Gas Temps]. Uh-oh.....

When I put the Pyro on mine I discovered it can nail a quick 1,200 if I push it, even running empty, here in the mountains. That means when I was towing that same load mentioned elsewhere it could have seen some pretty mean EGT's going on and I had no idea!

Therfore I believe that even 'stock' diesels NEED A PYRO!
 

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Pyro for me is totally important. that said I lucked out and my engine, with tons of power and the 120hp 4BTA model, did just fine here and never hit EGTs. But my head gasket started going (common on 4BTs in my opinion -- luckily a very easy & quick job minus the time for machining).. Then, my EGT gauge became crucial and I would have killed my turbo otherwise half way on a 14 hour trip in the middle of Nevada...! A
I would guess that capital 'A' saved your bacon? I imagine it wouldn't have held up nearly as well without the aftercooler? I think back to what I mentioned in other threads about towing that Chevy LUV truck with my Dodge truck and both loaded to their roofs, maybe as much as 13K? I'm sure the Pyro readings would have been real scary through the mountainous sections where I live. I can hit 1200+ real easy running empty if I nail it on a steep hill, and that's EMPTY! Have to say, 'Divine Providence' or mine might have been toast as well....
 

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Also on the pyro subject.
Even a stock engine that's starved of air (blocked air cleaner etc) can have EGT's that rocket.

My truck before I got it had a restrictive aircleaner, another tight restriction in the intake to the turbo, a pump that had been wound up and no intercooler.
I hate to think how hot it must have got.
 

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Thanks for the reminder, I'll add that to the maintenance and checkout routine. I'm in the high desert with almost continuous winds and lots of blowing silt or sand. Have to stay on top of that air cleaner maintenance!
 

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Others with more knowledge and experience will reply, but for me 'Safe' is up to 1,200* sustained. I believe Cummins allows you can run up to 1,300 but I won't guarantee that, and that is not a safe sustained temp far as I'm concerned. Reason being, that needle moves FAST FAST and the damage than can be done is, in some cases, near instantaneous. I've heard guys say that they didn't even have time to shut it down before the pistons were melted, but they were running hard or in competition at 1,500*+.

Brief excursions to higher temps are supposedly okay, but 1,500* is sure death from what I understand. So I'd say 1,200-1,250 and watch it, 1,300+ back off!
 

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Discussion Starter #16
Sounds like a pyro is cheap insurance. This is one more thing I wouldn't have known if I had not found this site. Thanks.
 

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Ha haha, yeah, I wish I would have had this site for reference when I did my own 4BT swap! Fortunately some of the members here helped me via e-mail and some other non-4BT sites we frequent. It can save you thousands and a whole bunch of grief.
 

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Cummins says 1350 pre-turbo IIRC from the manual. 1200-1300 is plenty safe most out of the box engines run in that range from cummins without any mods when opperated at WOT under load. the new cummins trucks would scare you some are pushing 1300+ pre turbo without any mods from the factory with a load

ver 1350 for a sustained period of time over 2-3 minutes can be detrimental to the rings. rule of thumb 30 seconds to 1 minute max over 1300-1350 remember aluminium starts to melt at 1350 degrees and forged aluminium pistons can only take sustained temperatures over thier melting point before they start to soften

Brief excursions to higher temps are supposedly okay, but 1,500* is sure death from what I understand. So I'd say 1,200-1,250 and watch it, 1,300+ back off!
Good advice though ive made a point of avoiding any excursions over 1400
 

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Yes, agreed Dusty! Problem with going over or to 1300 is that the needle CLIMBS FAST! On a fairly straight road pulling a load you can monitor temps and hold what you want. Where I live it's all mountains and wild twisty roads, so it's really hard to drive and eyeball the EGT's at the same time, especially at high temps. I know pullers do it all the time with high temps, but they also end up rebuilding a lot.

What I'm saying though is that it's not only the maximum safe temps, it's also the current driving conditions while you're experiencing those temps. Always better safe than $orry....
 
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