Dakota 4BT swap & intercooler

[driverswanted]

I understand that the 4bta aftercooler is not as efficient as an intercooler. Does anyone know roughly what the performance gain with an intercooler on the 4BT might be? I know that it's going to depend on surface area and flow restriction changes, but would like to read other's thoughts on this.

See a lot of non-cummins type intercoolers available on E-bay. I would like to explore using one of these in a Dakota/ 4bt setup. Anyone have intake CFM info on 4bt and what other intercoolers might work?

Looking for the 4bta CPL# 0986 performance chart. Anyone have this?



Project update: Should be buying engine in 1-2 weeks. Purchase of 1999-2000 Dakota to follow in about March or April.

 

[moparguy]

DW, I don't have the info you seek, but I do like the way you think. I've been looking around for something like you're building, already built. No luck.



I've also been on the look out for wrecked van with a nice 4BT in it. I'm thinking a 1/2 ton Dodge would make a good home for the diesel drivetrain with appropriate upgrades to the front frame.



Of course the nicest package would be one of the new 4 door Dakotas with a inline pump 4BT cranked up to about 250hp, 400/500 ft. lbs, appropriate sound mitigation installed along with structural upgrades, that would be sweet.



Good luck and keep us posted.



Ronnie

 

[driverswanted]

4bt/Dakota

Yes... . The Dodge not following up with a Dakota/ Cummins combo got my underware in such a wad that I decided to take matters into my own hands. Working on rear axle selection too. Really worried about the high strain on drivetrain gears at these low rpms. Although I don't plan on going to 12,000-15,000 lbs. towing like I hear others doing, I want the comfort in knowing that I can tow my 5,000 lb. boat several hundred miles without a worry. Doing this also because my '92 Ram 350, Getrag 360 started puking :--) while towing the boat. (that's another project).

 

[HoleshotHolset]

Find CFM requirements of a 6BT and subtract two clyinders.....



I would think that if you found an IC core that flowed 1000cfm... you'd be doing just fine.



A F*rd Powerjoke IC is cheap ( I have one brand new in the box... . ) and they flow okay for the price.



Matt

 

[driverswanted]

intercooler for 4bt

Thanks HoleshotHolset,



I looked in my '91 350 w/Cummins manual. Didn't find CFM data there. I'll just work with the 1000 cfm figure or look at the f#rd intercooler. Hope it fits. One thought I had was that if space in the Dakota gets cramped maybe two smaller paralleled coolers at separate locations would work also. Also see some variations with periscope type air scoops in front of IC that allow the IC to be positioned out of direct airflow if space dictates.

 

[HoleshotHolset]

The two intercoolers in series has been done... . and it works great where you don't have room for one big one. I have worked on two vehicles with this type of setup... . and it's pretty cool.



As long as you get plenty of ambient air through it... it'll be fine.



The Dakota is kinda tight forward of the radiator support... . which is precisely why some folks mounted their radiators in the bed and nixed the intercooler altogether.



Matt

 

[JLEONARD]

The air flow specs for a 4B-250 hp marine series engine (cpl 2197) is listed at 480 CFM @ 3000 rpm and the 155 hp version (cpl 0741) is listed at 270 CFM @2800 rpm.



Hope this helps

 

[driverswanted]

4BT Dakota

Thanks Jleonard,



Do they state the pressur edrop with that figure?

Do you have a performance sheet on a cpl 858? I'm working out my rear ratio and tire sizes to fit the nv4500 so I can hit best mpg at 60-65 mph while in a no load 5th gearcondition and just forward of the peak torque curve when towing in 4th gear. Like backing up on torque curve into higher torque when slowing down on a hill (just like my '91 CumminsRam 350). I'm using the cpl 2303 (110h. p. )curves right now but would like to hit the numbers right on the head by using the cpl 0858 curves.



See you have the 16cm turbo. Does that fit the 4BT?

 

[JLEONARD]

No, I don't have any other data sheets, just those two.

I do have a repair manual at home that lists some specs for other 4b engines... . I'll take a look tonight, but it will only list max figures... . no curves.

No idea if the 16 cm housing will fit... . I am not familiar enough with the 4 cyl manifold.

Good Luck

Jay

 

[HoleshotHolset]

From what I have seen, the 4BT manifold is just like the 6BT... . only it is missing two cylinders and the turbine flange is at the rear of the manifold/engine.



The flange must be the same as the 6BT..... I saw a Jeep in Muncie with a rotary pump 4BT/HY-35 combo.



Matt

 

[driverswanted]

This HY35w is listed as a 9 or 10cm sq. "single port". 20. 5:--) psi max boost fitted to the year 2000 ISB. At Geno's site I see this but I don't see the waste gate in the picture. Is it aft of the flange point? Wonder If this will force me to cut the firewall. This would probably be pricey coming out of a year 2000 vehicle.

 

[HoleshotHolset]

You could probably get an HY-35W used for about $300... look around. The '01 and up automatic transmission 24-V guys get rid of 'em for something bigger... .



Matt