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I have seen many succesfull proyects swaping 4bta....but where is the happy medium between POWER....ECONOMY AND REALIABILITY ...Where we stop triying to squeeze HORSE POWER out of the engine to achive complete realiability or top MILES PER GALLON ....I know that somebody here have the perfect recipe
 

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I think it has been proven that there isn't a happy medium, Panama! Reason being it's a matter of personal self control and not a need for power.

I just took a 700 mile trip on a little used highway, plus into a very congested area near LA. I went through steep mountains with lots of twisties, wide open flats with no cops, and then on crazy freeways full of nutballs in a huge hurry, and through city areas at a rush hour. In my 40 year old Dodge full size I had no problem at all keeping up or pulling ahead, within reason, with a bone stock 4BT/NV4500/4.1 gears.

That's the key: within reason! If I had 4 wheel independent suspension, S-speed or higher rated tires, 4 wheel discs and Porsche handling, well, I could have gone lots faster. Regardless, I was never in NEED of more power!

Will I turn it up? Yes, because I have the parts and it's free. May help some on mountain roads, but I don't need to do it. Folks are folks, and some will turn it up 'til stuff breaks right & left and some less, and some not at all. That's why there's so many different kinds of cars and trucks and powertrains available in new cars, and why some people still drive their 40-50 year old warhorse trucks in the slow lane. :)
 

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I have seen many succesfull proyects swaping 4bta....but where is the happy medium between POWER....ECONOMY AND REALIABILITY ...Where we stop triying to squeeze HORSE POWER out of the engine to achive complete realiability or top MILES PER GALLON ....I know that somebody here have the perfect recipe
While I am FAR from an expert on diesel tuning, it has been my observation that a diesel tuned for maximum power but driven in a miserly fashion will produce very economical results. I know several people that have newer electronically controlled diesels (GM, Dodge, & Ford) that have installed one brand or another of an adjustable tuner, and every single one of them have said that they get the best fuel mileage with their tuner adusted to the highest HP setting. One guy with a Duramax said that he leaves his on the next to the highest setting even though it gets slightly better mileage on the highest because it is almost undriveable on high. He said that no matter how gentle he tries to be, every time he accelerates from a stop it spins the tires and then barks them again on the first two shifts! :eek:

As far as personal experience, my truck gets better mileage with the pump turned up than it did before, providing I keep my foot out of it; I keep a spreadsheet of my mileage and drove the thing as easy as possible for one tank after I turned it up and (compared to an month earlier tankful where I babied it) it got 1.7 mpg better fuel mileage. However, if you crowd the throttle a bunch you will definitely pay for it in the mileage department! Tuning for power in a diesel is tuning for efficiency, and the gains will be reflected at both ends of the power - mileage spectrum; the result is your mileage will directly reflect your driving style.
 

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It's very subjective.
I'm sure Cummins would say that the engines go out their door with the best compromise of power/economy and reliability.:D
 

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I keep all my 4b's Bone Stock. I want every bit of reliability that Cummins Designed into them. I have never been at a loss for power/performance.

Paul
 

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WHAT, yes it is good. sheeeeesssh. look at this. clip.
my turck


Now. blowing black smoke is good. it is just unburned fuel. my truck blows black if i mash the gas. i have a lot of mods. but if it smokes under full booooooost then it is bad. but if it smokes untill you build boost then you are good. more smoke means more fuel more fuel mean more POWER.:happyfinger: :happyfinger:
 

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Now wait a munte, smoke ain't power! Smoke is UNBURNED fuel, or partially combusted fuel going out the tailpipe without doing any horsepower work! It means that the air/fuel mixture is too rich at whatever rpm it smokes at.

True, with the fuel turned way up to the point of smoke you would have more power, but you can have the same power without the smoke. That same over-rich mixture may add more power at a different rpm, but the black stuff isn't power at the rpm it's smoking at. That's the way I understand it anyway.

Pullers, race rigs etc. are turned up to their limits to be sure they're getting all the fuel they can get jammed in the cylinders, but the smoke is still unused power going up the pipes.

I'd have to agree that it isn't at all good for the diesel image, especially when we're working very hard to convince the public and the air cops EPA that DIESEL IS THE ANSWER FOR THE FUTURE AND NOW! Almost like trying to convince the cops that hotrods are cool by doing burnouts in front of the cop shop! Doesn't help, and we really do need all the public relations help we can get right now.
 

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Now wait a munte, smoke ain't power! Smoke is UNBURNED fuel, or partially combusted fuel going out the tailpipe without doing any horsepower work! It means that the air/fuel mixture is too rich at whatever rpm it smokes at.

True, with the fuel turned way up to the point of smoke you would have more power, but you can have the same power without the smoke. That same over-rich mixture may add more power at a different rpm, but the black stuff isn't power at the rpm it's smoking at. That's the way I understand it anyway.

Pullers, race rigs etc. are turned up to their limits to be sure they're getting all the fuel they can get jammed in the cylinders, but the smoke is still unused power going up the pipes.

I'd have to agree that it isn't at all good for the diesel image, especially when we're working very hard to convince the public and the air cops EPA that DIESEL IS THE ANSWER FOR THE FUTURE AND NOW! Almost like trying to convince the cops that hotrods are cool by doing burnouts in front of the cop shop! Doesn't help, and we really do need all the public relations help we can get right now.
Well said! Good analogy--burnouts in front of the cops.:)
Bob B.
 

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I agree. Banks built a drag racer featured in Diesel Power that blew smoke only from its burning tires-it had plenty of power. In that article, the founder of Banks Power said they refuse to build any horsepower mods that blow black smoke because it is bad for the diesel image and it is wasted energy. If it blows black, it means you need to tune it better is the gist of his opinion.

Just think about what blowing black did for all the diesels that came out in the early 80's. If they had at the very least burned clean AND been gutless, maybe there wouldn't be all this smog crap on the newer diesels.

Blowing black smoke is irresponsible and is going to screw us all in the end. (no pun intended.)
 

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I agree. Banks built a drag racer featured in Diesel Power that blew smoke only from its burning tires-it had plenty of power. In that article, the founder of Banks Power said they refuse to build any horsepower mods that blow black smoke because it is bad for the diesel image and it is wasted energy. If it blows black, it means you need to tune it better is the gist of his opinion.
When I was in the US (christmas 02 I think) there was a diesel tuners ad on tv which showed a lwb dodge doing donuts and blowing out a ridiculous amount of smoke.

That crap does no-one any favours.
 

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4bt upgrages

I'm looking at dropping a 4bt in my 1/2 ton. Any reccomendations on a moderately priced upgrade? Could i use a small radiator as an intercooler? I probably can't afford a new turbo but i think there are rebuild kits that use ball bearings instead of journal. Will also make my own exhaust but I don't know what size and if i should bother with a dpf or converter. I may send the injectors out to be machined (i think its $40 apiece). My budget may be eaten up by a transmission or new diffs. What is the best way to go going from gas to diesel (running 1/2 the rpm's)? Any help would be great.
 

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Yea. but my truck i turned it down so no smoke. But the power of having the smoke was a big differance. the smoke only happens while i biuld up to 10psi then it goes away. up to 40psi it burns clean.:grinpimp:

Now wait a munte, smoke ain't power! Smoke is UNBURNED fuel, or partially combusted fuel going out the tailpipe without doing any horsepower work! It means that the air/fuel mixture is too rich at whatever rpm it smokes at.

True, with the fuel turned way up to the point of smoke you would have more power, but you can have the same power without the smoke. That same over-rich mixture may add more power at a different rpm, but the black stuff isn't power at the rpm it's smoking at. That's the way I understand it anyway.

Pullers, race rigs etc. are turned up to their limits to be sure they're getting all the fuel they can get jammed in the cylinders, but the smoke is still unused power going up the pipes.

I'd have to agree that it isn't at all good for the diesel image, especially when we're working very hard to convince the public and the air cops EPA that DIESEL IS THE ANSWER FOR THE FUTURE AND NOW! Almost like trying to convince the cops that hotrods are cool by doing burnouts in front of the cop shop! Doesn't help, and we really do need all the public relations help we can get right now.
 

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My question is if you turn it up, and drive it softly what does that do for longevity of the motor?
 

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I'm of much of the mindset of the original post and I want an incredibly reliable vehicle too...

I do mild turbo and will probably do really mild injectors but that is it. All factory parts, as little smoke as possible. Not that I need it up here but I found the turbo in particular (maybe something with the altitude up here at about 6-8K feet) really woke up the engine, with little if any loss in mileage. I never really felt I needed it but if its is free or cheap power with little drawback I figured why not...

The turbos have been very low mileage off 6BTs from guys bombing out their trucks and the injectors have been new from Bosch, so no loss of reliability at all IMO..
 

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smoke means power POTENTIAL

If it's smoking get more air to it. The ideal air/fuel mixture will burn clean and produce more power. Smoke is unburned fuel which in turn is carbon monoxide, I used to use that to weld gas tanks as the CO would displace the oxygen and the tank could not blow up. Same thing in the cylinders. Too much fuel is actually hurting performance by choking it. True it is making big power but not as much as one that actully burns the same amount of fuel with a good mixture.
 

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Smoke Matters

With diesel fuel currently priced at $3.85 - 4.50 a gallon, I not only agree with comments about the diesel image tarnished from excessive smoke, but moreover have to question the logic of driving huge personal diesel powered vehicles and coming to the comment board with racy power-making sorts of what's possible and how long can I rip into it queries. Can you afford it? I can't...

My daily commute is 68 miles one way, so each day I put at least 136 miles. My Cummins powered one ton cost about 30 dollars a day to commute - it is parked unless I need to tow.
30 x 5 = $150 per week or 600 per month.
My Mercedes diesel costs for the same trip about 19 per day.
19 x 5 = $95 per week or $380 per month.
My VW diesel pickup cost about 14 per day to commute.
14 x 5 = $70 or about $280 per month.
Compare 600 to 380 to 280
I heard VW has a 3 cylinder car that gets 70 per gallon on # 2. I could make a payment of $450 on one of them and break even.
I have converted my one ton, converted an old Bronco to Cummins, but let's be realistic, fuel prices have robbed me of driving them.

four months ago, the VW pickup only costs me $9.00 daily. Yes the rise in fuel price has robbed $5 daily, 25 weekly and 100 monthly from my budget which has not increased.

The above calculations do not include errand or other trips.
Smoke matters.

Wayne
 

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30 MPG would be a Daily Driver

If my Bronco 4BTAA would get 30MPG, it'd be a DD. I only gets lower-mid 20s. Currently winter-time yard art. Will drive this summer.

The MAIN reason I drive my Bronco so little is I have yet to find a set of decent 68-77 doors. Have a set of 66 which strikers don't align- to keep the rain out when parked, removeble hinges for summer drives. Found many rusted doors, still looking for a good door set.

As for the VW, re-powered with the 1.9TD (AAZ), and the power and torque is so much superior to the factory 1.6 natural diesel. Won't pull down. Installed cruise control, can run with or faster than traffic with EZ. BTW - used the 3.5" muffler and pipe bends off the Frito Lay 4BTAA van for my VW exhaust. Certainly has no back-pressure.

Wayne
 
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