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4bt in a 1500 4x4 ?

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MEby

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I was discussing what kind of fuel economy could be gotten out of a 1/2 ton pickup with a 4bt with a friend of mine. He thought the 4bt would be underpowered for the application. (define underpowered :-laf :-laf ) His idea was to put in a 6bt instead, but i'm wondering what fuel economy increase would you gain over a 3/4 ton with a cummins? How much difference would a thousand pounds make? Assuming thats how much weight you lose. What if you took a 4bt and cranked on it to produce somewhere in the vicinity of 200hp, would that be sufficient for a half ton? The reason for this discussion, I dont need the 1 ton truck I drive. I wouldnt even need a 3/4 ton, I could get by with a 1/2 ton. I am too hooked on diesels to give them up for a 1500 4x4 gasser and get worse fuel economy with it than on my 3500 4x4 cummins.
 
You would definitely need to beef up the front suspension, the 4bt is light for a diesel but still heavier than a gasser. I know a few guys that had 4bt's in their early 80's Chevy 1 tons that made 23-25 mpg. The 1/2 ton , as long as everything is tuned right and the right gears/transmission, should do just as well. I've even seen a company that does 4bt swaps into Jeep Wranglers. They put in Dana 44 front axles w/ a mild lift to clear the motor and they advertise around 24 mpg if I remember right. The only thing is cost. If you have a donor motor/truck already and a good shop, might be cost effective, but how many years will it take to pay for itself. Though, how can you put a price on cool factor?
 
what about a dakota? would you improve fuel economy with a 4bt in it, again i'm assuming you would lose some more weight comparing it to a 1/2 ton.
 
6BT-Dakota said:
I get 20-22 mpg in my 6bt dakota



would you mind filling in your sig, i'd like to see what youre running for trans, gears, tire size, and power. :D



only 20-22mpg? there are some full size 3/4 ton cummins getting that. no offense but I may as well drive a full size pickup. am I off base?
 
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I just read a thread about a guy that put a 4BT in a F150. He has it turned up to 165hp/400ft lbs and gets 30+mpg. I'll retrace my steps and see if I can find it.



-Kevin
 
MEby said:
would you mind filling in your sig, i'd like to see what youre running for trans, gears, tire size, and power. :D



only 20-22mpg? there are some full size 3/4 ton cummins getting that. no offense but I may as well drive a full size pickup. am I off base?





I have a myspace and other profiles that you can check out:



http://www.myspace.com/6BTDAKOTA



http://pavementsucks.com/forums/viewtopic.php?topic=97673&forum=11



http://pavementsucks.com/gallery/viewride.php?ride_id=4665
 
I think I understand were your fuel economy went, I looked at the picture of your dakota. :D nice truck. :cool:



Now for another question. What if I put a 4bt in my old 2wd 64 chevy? Fuel economy? I think it currently weighs approx 3500 pounds.
 
4BT mileage

My 85 RAM is getting 25 MPG right now. Towing a 5,000# boat behind drops it to around 17 mpg. The MPG numbers should be a little better if you have the P7100 pump. My numbers are verified with a GPS. These old trucks can have 5-10% odometer errors especially if we change the wheel sizes. I'd take some of these claims of 30 plus GPM after bombing with a grain of salt unless verified with a GPS. Still ya gotta do the drop in for the cool factor and to send the message that we want more efficient vehicles like diesels in dakotas and 1/2 ton trucks.
 
If you look at the picture links that I have posted you will see why I only get 20-22 mpg. I think the 38's have a lot to do with it. BTW my Dakota has a 1-ton Ford Suspension.
 
Yeah, I looked at the size of those tires and lift and thought that your doing well to get the fuel economy that you do.





I got to thinking, I used to own a mercedes 300sd. the engine was a 5cly turbo inline that put out 120 hp stock (diesel of course). I got an average of 27mpg. the car weighed in at 3750 lb according to the owners manual. thats close to the chevy in weight. I have a place here were I likely could buy the engine and trans (auto :( ) for several hundred bucks. I dont know what kind of hp could be produced. I had my car tweaked to approx. 140hp and producing 22lb boost. :D no idea on egt. I did have a diesel shop tell me if I sent in the injectors, they could have them edmd to produce another 40-50hp. Unfortunatly the injection pump had no full fuel screw to mess with :{ the pump (bosch) would have to be taken apart to see if more fuel can be got. sorry for the long post. just some thoughts. matt
 
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