4bt performance

[PAULO]

I am wanting to start a project in the near future and am interested in putting a 4bt into a full size pickup. What kind of HP/torque can be gotten out of this engine and who makes the parts to do it? I would like to get at least 400lb/ft. Are there injectors or a box that could accomplish this? Thanks.

Paul

 

[RoadGoesOnForever]

You will easily be able to get that much torque. They have 333 stock for the rotary pump motors I believe. Anyway, if its a rotary pump like out of a bread van you can do the same things that you do to a first gen dodge so that forum would be a good place to look. Injectors, some pump tweaks, maybe a modified turbo, and possible propane injection will get you well over what you want. If its an inline pump motor then you can do the same thing as the 2nd gen dodges like cam plate, injectors, governor kit, turbo, etc. Hope this helps.

 

[philb4]

4BT in 84 chevy dually

All I can say is that performance is uninspiring at best. I have a 4bt in my truck 4sp 3. 73 rear. The rating is 105hp but modified to 120 at rear wheels. With 4. 10 rear I towed 18,000 lb trailer cross country 13mpg but engine redlines at 65mph. With the 3. 73 I towed 12,000 semi from MN to CO ok. 0-60 times in hot weather is bad but once the turbo comes up to 5lbs boost it starts to pick up. On the plus side is no repairs in 200,000 miles and 28mpg on the highway,12 hours on a tank. Recomendations... use a light truck mines 6300 lbs empty ,5speed or a gear venders splitter(the space between 3-4 is too wide turbo slows down)Get the 6bt as I will use this engine in my White 3000 with a 3 speed splitter,lots of hills in colorado. Surprizing the engine performs really well at 13,000 feet,turbo lag is all but gone. One solution is to use a ford 3. 8 supercharger,it mounts like an accessory with a ribbed belt for low rpm boost. All in all I will save this engine for another truck project but hope to keep total weight down to 3000 lbs and expect performance to be much better. phil

 

[Mark_Kendrick]

philb4





What is your max boost and redline?

 

[philb4]

redlines

Redline at 3200 rpm boost in denver 14 psi but 18 at the mountain passes. exhaust is 4" down pipe to 3" straight system out the back and as with my older trucks they consider the turbo a muffling device.

 

[Mark_Kendrick]

I bet a set of injectors/plate and some turbo work would help a lot.



1lb boost = 10 hp for (good rule of thumb) for 24v 6BTs, so only 14psi can't get over 140hp for a smaller motor.



I thought I had heard or getting 200+ hp and 3-400 ftlb out of a tweaked 4bt.



As for the low speed a Gearvendors overdrive will fix the lack of headroom for the highway, but you'd need a good bit more juice to push it at the higher ratios.

 

[MUDDY]

http://cgi2.x-pointcgi.com/~dieselrepower/Scout_4B.html



this guy is getting 460 lb ft tq

 

[philb4]

4BT on Ebay

4bt on ebay with choice of trans # 600970505

 

[Mark_Kendrick]

I have a 3/4 T W200 that would love the 4bt but . . I'm buyin a slew of go fast goodies this month

 

[Mark_Kendrick]

Muddymess,

that guy at . . http://cgi2.x-pointcgi.com/~dieselrepower/Scout_4B.html

is not using an intercooler. I'm about to upgrade my 5. 9 to a B1, just think what a intercooler and a Hx35 would do for one of those!!



I bet it'd get over 200 hp and 400+ lbft.

 

[JLEONARD]

There is a 4BT marine version that is rated at 250 hp at 3000 rpm.

Torque tops at 491 ft lb at 2200.

It uses the P7100 series pump.

Thought I'd pass that along.

 

[Mark_Kendrick]

What kind of aftercooler is it using?

 

[JLEONARD]

The marine version uses a raw (sea) water aftercooler. So you will not cool the air charge as much with an air to air aftercooler, so you may fall a little short of the 250 hp.

Here's a link to a page that will show the power curve.



http://www.cumminscpmarine.com/htm/recreational.html

 

[Mark_Kendrick]

I can't beat the open ocean for ccoling but I bet 36lbs of boost 'd help An air to air off a 5. 9 would probably come close. Not qite as cold but air temp should always be under 150*.

 

[JLEONARD]

Mark,

Cooling that kind of boost down to 150 deg F might be a stretch?

I have never seen any figures for this on a vehicle using an air to air cooler, but I would be interested in the data if you have any.

Has anyone done this? Might be interesting .



I can speak of experience on a Perkins marine T6. 354 engine (6 cyl, 354 cu in) with a sea water aftercooler. This engine only builds about 10/12 psi of boost at 2400 rpm. Typical turbo outlet temps at this rpm are 230 deg F. The intercooler using 70 deg seawater, gives an outlet temp of about 150 deg F. starting at 0 boost and taking data points every 200 rpm, the temp differential gets larger with higher boost as one would expect.



My Cummins 6BTA 270 hp marine engine has a coolant exchange meduim for its aftercooler so the boost air can never get below 170 deg once the engine is warm. I'm sure it's not even close to that. (especially at over 30 psi). I think I'll measure it this summer just for something to do!



This is interesting. I'd like to hear how you do on your project!

 

[Mark_Kendrick]

Its going to be determined by outside ambient temp. If you have 325* going into the cooler and 70* ouside air IF the cooler is big enough getting below 200*should be acievable. . I have not measured my in take temps but I'm also flowing air for a 5. 9. The 4bt is going to flow 33% less air at the same rpm. The same cooler should give a marked decrease in temps on a 4bt compared to a 6bt application.

Many of the 4bts come with water to air after coolers. you could exit the water to air into an air to air to reduce the temp even further.

I've been considering a water to air on my truck before the intercooler. It would get the temps down below 300* before the air to air.



I don't know if its possible for the 4bt pump to move enough fuel to produce the boost.



I'm just hacked off because I don't have the time and money to test it right now.

 

[JLEONARD]

Sounds like you have a plan .....

Good luck with the project!

 

[Mark_Kendrick]

JL, Yo u got me to thinking... I'm not at my truck right now butt... I think the return from the radiator is on the passenger side. Under most conditions this air is below 200*. All that would have to be done is to build a small radiator of the post turbo air to flow over before entering the a2a cooler. Build a cover for it w/3" inlet/outlet and its set. The problem would be space on that side of the motor for such things. It's getting pretty crowded w/the oil filter and all.



It could actually be attached to the a2a inlet.



Food fro thought.

 

[SClements]

I PUT A 4BT IN MY JEEP, TWEAKED THE PUMP, CHANGED TO A 12CM2 HOUSING AND HAVE AWESOME POWER & TORQUE. IT GETS 32-33 LBS BOOST PULLING THE JEEP BODY AROUND. NEXT WILL BE SOME INJECTORS. NEED TO DYNO TO SEE HOW MUCH HP & TORQUE.

 

[Mark_Kendrick]

Cool!. . quit SCREAMING post some pics . . sounds interesting.