Trucks Tv Xj build on Spike TV Sunday

tbburg said:
A dynometer run is about the hardest thing you can do to an engine. Even drag racing won't put as much stress on the motor/powertrain. I know they were doing it for TV, but putting a 100K-mile motor with a knock on a chassis dyno is kind of stupid.
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what difference does it make? they were planning on rebuilding the motor anyway.
 
whats so hard on it? not getting cool air flow? sorry if its a dumb question, im sure I could find it if i spent some time on google. but im feeling lazy this one time.
 
chedisme said:
whats so hard on it? not getting cool air flow? sorry if its a dumb question, im sure I could find it if i spent some time on google. but im feeling lazy this one time.
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i imagine its the numerous wide open throttle runs used to get their baseline numbers.
 
chedisme said:
whats so hard on it?
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It wouldn't surprise me if most of the cars on the road have never seen 100% power. Auto industry's dirty little secret: The engines are not designed to put out 100% power. Most of them are designed for 15-20% continuous or less.

If you really romp on your jeep on the street, or off road, how long do you keep it floorboarded? How much of that time is the motor producing max power?(answer; if you're still accelerating, in any gear, at any speed, the motors probably not producing max power for that engine speed :D)

To pull a dynamometer run, you start at what ever RPM the test starts at, then load the engine until it can't speed up at WOT. 'Take your reading, then start speeding up. Through the whole run, the engine is operating at maximum power. The motor(any street motor) can't take that for long.
 
tbburg said:
It wouldn't surprise me if most of the cars on the road have never seen 100% power. Auto industry's dirty little secret: The engines are not designed to put out 100% power. Most of them are designed for 15-20% continuous or less.

If you really romp on your jeep on the street, or off road, how long do you keep it floorboarded? How much of that time is the motor producing max power?(answer; if you're still accelerating, in any gear, at any speed, the motors probably not producing max power for that engine speed :D)

To pull a dynamometer run, you start at what ever RPM the test starts at, then load the engine until it can't speed up at WOT. 'Take your reading, then start speeding up. Through the whole run, the engine is operating at maximum power. The motor(any street motor) can't take that for long.
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Hmm thats not how I've seen it done in my personal experience. Back in my UTI days in Hot Rod U I personally drove a Ford Lightning on a chassis dynamometer. I basically drove the car up to speed to get it through all gears, then hold that speed as if you were cruising at around 40-50mph or so, then they said GO! and i floored it, the trans downshifted and it pulled through the RPM range from about 3000 rpm all the way to 6000 rpm or so at which time I let off the gas. While I was in the cab, it literally felt no different than flooring it on an onramp till you get up to 90mph or so. There was no lugging or anything abnormal. About a minute later the intructor posted up the Hp and Tq number up on the screen.

Before that, I took my mustang to a chassis dyno and stood by it while the guy put it through its paces. My mustang was a manual tranny, but otherwise the process was no different. He brought it up to speed and cruised in 4th gear, then pushed a button and floored it and took it to 6000rpm. As I was watching it, it also seemed no different than if i were to do the same thing on the freeway- no extra lugging or extra time at a certain RPM.
 
Well, that was disappointing. Apparently they finished the motor, but didn't cover the re-install or dyno the result(yet). 'Would have liked to see what if any tuning was needed to get it running.

'Got a long arm kit though! ( ? )

Maybe I missed an episode?
 
Well, I just went and looked. Episode 6 was engine reassembly and paint the engine compartment, episode 7 is driving it around. 'Didn't miss anything. Maybe they'll cover tuning when they dyno it. 'Hope we don't have to wait 4 months for the next installment.
 
I just ordered the two episodes ,6&7 to see what I missed, the thrill is gone now--
Wayne
 
tbburg said:
Well, that was disappointing. Apparently they finished the motor, but didn't cover the re-install or dyno the result(yet). 'Would have liked to see what if any tuning was needed to get it running.

'Got a long arm kit though! ( ? )

Maybe I missed an episode?
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Hey guys, I just watched the episode, and at the very beginning, they state that they are not planning to dyno it until it has broken in. They talk about potential tuning as well. I think we can expect to see it eventually. :thumbup:
 
and they put on a Rustys longarm kit with the steering and SYE.

they did say some things i dont agree with though. they said instead of properly bumpstopping, they just lifted it higher. they said bumpstopping would defeat the purpose of a suspension lift. idiots.
 
chedisme said:
whats so hard on it? not getting cool air flow? sorry if its a dumb question, im sure I could find it if i spent some time on google. but im feeling lazy this one time.
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The difference is the load put on the vehicle while strapped to the dyno. My background before buying a jeep is building/tuning street cars. We tune them on the dyno for a baseline tune and fine tune the vehicles on the street.

When it is strapped to the rollers on a dyno you are asking alot out of the motor and drivetrain to spin usually stationary drums that weigh ALOT. Where as on the street the load is not nearly as great. For example when tuning a car or looking for power output a vehicle is ran on a dyno in a 1:1 gear typically 4th in a manual trans or 3rd in some Autos and the test is performed from 2500-redline. Normally when you run a car WOT you are not in a 1:1 gear situation starting at such a low rpm.
 
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jeez, if the Rusty's crap isn't enough, they 'space' out the lower lift shocks with those screw on shock pin extenders to make them work for now.

it would be interesting to see what they would use if they weren't sponsored by certain people/companies.
 
with every episode they drift further and further from being "cheap".

someone should make a list or every dumb/wrong thing they say and mail it to them.

I hope that thing folds like a taco on them!
 
No offense, but you guys are all pretty amazing.

I'm sure people complain left and right that there is no xj coverage, when they bring it to you, you spend all day ong criticizing every aspect of it.

I am in no way saying these guys are perfect, they have there share of "special moments" but at least they are airing and doing some stuff with the xj.

As for the project, it started like the majority that I have seen here on naxja.... A cheap fixer uipper. Now after a few years of wheeling, many of those cheap once fixer uppers have strokers, and dana 60s, etc etc. So they went and kpt building it after the initial "cheap" build.
I think its cool they have kept moding and airing the show for XJ peeps to watch.

anyways, those are my two cents, you can all now carry on criticizing the show.
 
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