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6.5TD DB2 vs 6.2 DB2

A

Acesneights1

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Is there any differnece between a DB2 off a mid 80s 6.2 vs a DB2 off a 93 6.5 TD ? Which would be better to use on my CUCV ?
I'm going to run a 6.5 Turbo setup and eventually use the 4l80e with a TCI controller which will require some sort of TPS. Does the 93 have a TPS also is there any difference in the fuel rates between them ? My CUCV needs an IP anyway so just trying to figure out which one is the best to replace it with.
Also any truth to the rumor that 6.5 IP lines are slightly bigger than 6.2 ?
 
I have rebuilt quite few of these DB2 pumps, the 4911 pump is the mechanical pump to have if you are running a turbo with a mechanical pump, Factory pump for mechanical and turbo setup.

The other mechanical pumps will work fine and you can turn them up to get more fuel than you can use. The DB 2 pump is pretty versatile, and easily turned up. Don't forget to adjust the transfer pump / case pressure and the timing retard (advance) ramp to get the best performance from your DB2.
 
Either of those will work fine with the 6.5TD, the 4911 from the '93 pumps a little more fuel in stock trim but the 6.2 IP can be turned up also. On these look for the "831" in the part number, like on the '93 DB2 831 4911. The 831 is the plunger specs - IIRC the 31 is .31 plungers. Some of the 6.2 IP's are .28... etc. Both should have the bosses for a TPS on them.
Don
 
The 6.5TD DB2 4911 pump has slightly larger 0.310 plungers, where as the 6.2 pumps were around 0.290 IIRC.

Yes, the 91 6.2's through 93 6.5 trucks and mid 90's mechanical vans ran a TPS.

I'd get a TCM from a 91-93 mechanical truck or the mechanical van/hummer TCM, instead of the TCI controller(which used to be the van/hummer TCM, maybe still is).
 
I would use a 4911 IP from an early 6.5

The pump can be turned down a little so it wont smoke like a forest fire and if you want to turbo the thing later just crank the IP back up again.

The plungers are indeed .310 on the 4911 and .290 on the 6.2 pumps.

A 6.2 pump will work even on a tubo'd 6.5 but wont deliver all the fuel that the rig can handle.

MGW
 
Yeah I kinda figured the 6.5 IP would give a little more. what about lines ? Can I use the 6.2 lines with the 6.5 DB or should I get new lines. Are the 6.5 DB lines same as 6.5 DS4 lines ? I will have a donor truck soon.
 
DS4 lines are different fitting and length at the pump, IIRC.

Early 6.2 lines were shorter, due to taller injectors, they will work but lines will fit tight(need a little tweaking) with the late 6.2/6.5 short injectors.
 
DB2 lines for a 6.2 will work with the 6.5 (DB2) Pump

Here is where the rub comes.

6.2 lines for a early 6.2 will work on the later DB pumps but the lengths are slightly different due to injector length and angle in the head.

Late 6.2 (91 and later) lines will work on the 6.5 with either DB2 Pump.

DS4 lines will only work with a DS4 pump due to the difference in the fitting on the IP end

Now Van lines are different yet as the angle of the dangle on things is slightly different from pickup stuff. Both the DB and DS stuff

Keep pickup with pickup and your pretty safe.

Real early 6.2 stuff had a longer injector body and a course thread on the injector where it screws into the head.

82-83 IIRC Then they went to the fine threaded injectors.

The angle on the injector hole in the head was changed to allow the turbo to be installed and clear things.
The late 6.2 (91 and later) had the same heads as the 6.5's did and will interchange and the injectors and lines will fit.

Now the late 6.2 can be retrofitted with a DS4 as long as you use the proper lines, the timing cover from a later 6.5 along with the lower timing sprocket that has the reluctor wheel and the short snouted ballancer.

The timing cover off the later engine will accept the crank sensor and will otherwise fit perfect.

The injectors from the DS equipped 6.5 (late) will screw right into a later 6.2 and the DS lnes will go right on.

You can use whatever other goodies that you see fit and mix and match till your hearts content.

Now that I have you totally confused.

Yes the DB will work, just use the proper lines.

If the lines you dig up wont lay right in and fit easily, its likely because they are not right..

Now I have seen an older set that was for the older heads that had the injectors angled out more used with the newer heads and just tweeked a little.

Not a good idea though and it looks tacky.

Now whatever you do, make sure that the lines are a matched set.

If you were to get some of one length and some of another you would end up with a crappy running engine as the length of the lines controls timing somewhat.

The lines are all the same exact length. This is why they have all those goofy oddball bends, loops and look like a chineeee Puzzle.


More confused????

Hope this helps you sort the bag of worms.

I always mark my lines as to what cyls the pairs fit even for a job that they are going right back on.


Missy
 
I'm not using a DS4. Just figuring out which DB2 to use with my CUCV. Sounds Like the easiest thing to do is use the same IP I have and turn it up. TCI makes a universal TPS if I go 4L80e route later on.
 
daustin said:
The DS pumps are fly-by-wire and the DB pumps have a real throttle cable, so you'd need to swap out the throttle pedal assy & linkage as well.
Don
Click to expand...

It's going into my bronco, I plan to rob the Entire drive train out of the truck.

see sig, I was wanting a either a 12v or a dt360, but I got this for FREE (was dads old truck) so thats what I'm going to use... Hopefully it will make enough power..
 
Dragot,
I would sell the 6.5. You'll get good money for it and then buy a 6.9. It's a damn good engine and will bolt right up to your truck and C6. It was an option on 83 Ford PU's so finding the right part to make it fit the Bronco should not be too bad. I always wanted to build a 70's Ford w/ a 6.9 and a Banks. Although stock 6.9 is no power house it was faster than a 6.2 so with a Banks turbo setup it should really haul....
 
Alright, I'll consider it. The only thing is the truck has aprox 270k on it and is in rough shape iirc I, doubt I could get enough to pay for a different truck, the other prob is as cool as that would be; IF I get a diesel 4x4 Ford I'm NOT going to want to cut it up.. It'd get added to my projects list, which is WAY to long as it is.
 
OK now that I am crosseyed, here's what I want to do. Will it work ?
Use a DB2 off a 92-93 6.5 on my 86 CUCV. Are the lines the same ?
 
Both pumps are basically identical on the outside, so yes it will work, bolt right on. The CUCV probably came with tall injectors, so the lines will be a little on the short side if using short body injectors, but it will work.
 
Should I hunt down 92-93 lines or are the stock 6.2 lines sufficient ?
Now here's a real question.... I never understood the whole pre cups thing but will that be an issue using a 6.5 Turbo setup on stock 6.2 heads ?
 
Use what ever heads you want, none of them will be wrong. The turbo heads will work on a 6.2 setup just fine. The 6.2 heads will work just fine also. The 6.2 heads may give you slightly better fuel economy, with or without the turbo.
 
OK now I'm still confused. The DS4 has 4 plugers that pump twice the fuel than a DB2?? There is supposedly a marine DB4 that can pump same as a DS4 ? Ughhh. Is there that much fuel delivery/hp difference between a 93 6.5/DB2 and a 94> 6.5 with a DS4
Here's what I want to do
Get as much HP out of my 6.2j as pssoible. It's an '86. If the DB4 can supply alot more fuel and I'm using a 6.5 turbo should I use that with marine injs and which lines ?
I'm all f' up. I jst want to squeeze as much as I can. I want this rig to sing. It's won't be a daily driver so I don't care about mpg. I want balls to wall.
:D
 
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