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Discussion Starter · #1 ·
TEX, Here\'s rest of story!

/wwwthreads_images/icons/smile.gif While you are "connected" and learning about turbo chargers, here's the REST of the story. DIESEL engines have no vacuum...the intake is wide open all the time.....so even at idle a huge amount of air is going through the engine. In fact, on naturally aspirated diesels, the volumetric efficiency at idle is very high due to neglible intake losses. Anyway, because they pass A LOT of air at idle, a four-stroke Cummins or Cat will cool from 1000 degrees F down to about 400 in seven or eight minutes. A two-stroke Jimmy will do it a lot quicker(more air)....about five minutes. So, you're a smart guy, you KNOW about engines, what about a gasser? How would THEY cool down a turbo? How long to you have to sit and idle after a hard pull up a very long grade to your sweetie's house? Does she have to wait and stew while you listen to a tape or is it as fast as the diesel? And another thing, IF your girfriend lived at the top of a long grade, would you be better off with a SUPERCHARGED Mustang or a Nissan twin turbo?/wwwthreads_images/icons/laugh.gif/wwwthreads_images/icons/laugh.gif/wwwthreads_images/icons/laugh.gif I can't get these moonguys/wwwthreads_images/icons/wink.gif/wwwthreads_images/icons/wink.gif/wwwthreads_images/icons/smile.gif to shut up. They claim that they have the answer already./wwwthreads_images/icons/crazy.gif

CJDave
I never believe any statistics unless my moonguys /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif made 'em up themselves.
 
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Re: TEX, Here\'s rest of story!

Drawin' a blank. Lower operating temps? And if the girlfriend lived at the top of a long grade (or anywhere else for that matter), the correct answer is "neither a nor b. I choose option "c" - a Jeep/wwwthreads_images/icons/wink.gif". But, if those were the only two possibilities, the blown Mustang over the turbos is my guess.

TEX

/wwwthreads_images/icons/wink.gif Got Mud?
G.U.M.B.O. Mud Racing
 
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Re: TEX, Here\'s rest of story!

You are actually lowering exhaust gas temps. My guess is that the supercharged Mustang would be a better bet as it doesn't create as much heat and the blower at idle is still pumping air which would cool (even though the compression heats up the air) versus the turbo which is not spinning. But then again....
 

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Discussion Starter · #4 ·
Re: TEX, Here\'s rest of story!

/wwwthreads_images/icons/smile.gif I'm letting my moonguy-in-chief/wwwthreads_images/icons/wink.gif of induction systems handle this and he says that the answer is that SUPERCHARGERS are belt or gear driven and do not use exhaust gases to make them spin and pump air. Therefore they don't heat up, and therefore they allow rapid shut-down just as a naturally-aspirated engine would. So girlfriend would not have to wait. As soon as you rolled in you could hop out and into her waiting arms./wwwthreads_images/icons/smile.gifGirlfriend would LOVE the Mustang and hate the Nissan twin-turbo./wwwthreads_images/icons/crazy.gif

CJDave
I never believe any statistics unless my moonguys /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif made 'em up themselves.
 
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Re: TEX, Here\'s rest of story!

You need to let a gas engine with turbo idle for about 30 seconds before shutting the engine off so the oil oil can get to it. As for a supercharger I think you can just shut them down.

Tim Springer
1980 CJ7
WALSTIB/wwwthreads_images/icons/wink.gif
 
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Re: TEX, Here\'s rest of story!

You can shut off a supercharged engine immediately. It's not the actual temp of the engine that is a concern with a turbocharged variety. If your cooling system is doing what it should, it is no hotter than a naturally aspirated engine. It's the exhaust gas temperature that gets super hot with a turbo and heats up the turbo itself. Once it's hot the oil in it needs to keep circulating or it will coke, or harden, on you. I've seen my EGT's go as high as 1200F on a steep climb and a heavy load and as soon as you take your foot out of it a bit, they drop right away. Superchargers do add heat though even if they aren't driven by exhaust. That compression of the air causes all those little molecules to move a lot faster and they create heat. I had a SBC with a BDS 6-71 blower on it and that thing always ran really hot (over 200F consistently) even with a very efficient cooling system. It didn't help though that I had the block bored .060 over and the cylinder walls were super thin!
 

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Discussion Starter · #7 ·
Re: TEX, Here\'s rest of story!

/wwwthreads_images/icons/smile.gif Very good explanation SnowTow....right on. Did you see that Tim? It's the oil-cooled center section of the turbo that is the problem. Did you know that aircraft had turbochargers during WWII? Yep, but without the space-age ceramics and so forth they could not allow high temps, so the exhaust pipes were run outside the engine nacelle and THEN to the turbo./wwwthreads_images/icons/smile.gif

CJDave
I never believe any statistics unless my moonguys /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif made 'em up themselves.
 
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Re: TEX, Here\'s rest of story!

Just a basic turbo question.
If there was a cooler that the oil that was going to the turbo ran through, would there be a quicker cooldown time? If the oil is cooler, won't it absorb the heat better and cause lower turbo temps? I have no reason for asking, just curious.

Ed
 

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Discussion Starter · #9 ·
Re: TEX, Here\'s rest of story!

/wwwthreads_images/icons/tongue.gif Yes.....anything would help. Actually, the turbo engines have a bigger oil cooler just because of that. But you see, the REAL problem comes when the guy shuts the engine off and the oil STOPS.....and cooks.....and cooks....and cooks.......into nice hard coke./wwwthreads_images/icons/crazy.gif

CJDave
I never believe any statistics unless my moonguys /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif made 'em up themselves.
 
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Re: TEX, Here\'s rest of story!

How about an after run oil pump??? Just like the electric fans on new cars, let just the oil circulate for a minute, or so, giving the Turbo time to cool, and not cook the oil that ends up there??? Just an idea, could also speed up oil changes, just unplug a line, and pump the oil out, and build Oil pressure b4 start-up.... Hmmm
BJ

to hell with it, lets go wheelin'
 
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Re: TEX, Here\'s rest of story!

CJDave, I'm sure that you already knew this, but in case you didn't...Many general aviation aircraft buit today still have turbochargers available as (very expensive) options. These allow us to fly at higher altitudes where the air is thinner, and still get sea level (dense air) performace out of our engines. They do, however, require a LOT of EXPENSIVE maintenance, and they usually decrease the service life of the engine by about 10%. I knew this piloting stuff would come in handy some day....

-Mike

.....Still waiting for the generous donor of a CJ-7....
Hey, I got an Idea....If everybody on this board gives me one part off their Jeep, a different part from everybody...I could build one! Yeah, thats the ticket!

1998 Dodge Ram 1500 Quad Cab 4x4 Laramie SLT Sport Plus--5.9L 360, auto, 3.92s, antispin, BFG A/Ts.
 

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Discussion Starter · #12 ·
Re: TEX, Here\'s rest of story!

/wwwthreads_images/icons/smile.gif That would do more to extend turbo life that anything you could possibly do.....especially if it had a fan-cooled coil in the same loop. Good idea!!!!! /wwwthreads_images/icons/smile.gif

CJDave
I never believe any statistics unless my moonguys /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif made 'em up themselves.
 

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Discussion Starter · #13 ·
Re: TEX, Here\'s rest of story!

/wwwthreads_images/icons/smile.gif You know,.....I THINK a friend of ours had a turbo on their Cessna 210......or was that fuel injection?....anyway they had the three-blade prop, and the "hopped up" engine./wwwthreads_images/icons/smile.gif That DONORJEEP thing isn't as crazy as it sounds. In the time that I have been reading this BBS and the old BBS as well, I have seen a SLEW of Jeep parts go begging. Guys upgrade, and the old stuff is underfoot. We have been able to find some good stuff for our CJ on this board, and someday I'm going to take a US-Canada map and draw in all the spots where our CJ came from in pieces./wwwthreads_images/icons/laugh.gif

CJDave
I never believe any statistics unless my moonguys /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif made 'em up themselves.
 
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