DB-4 Marine IP

[DA BIG ONE]

Any of you run or know someone that runs a marine DB-4 and hi-pops on a street vehicle?

[opto]

I don't know, but I know of a guy who runs a compressor and db4
He's in another forum I'm a member in

[quickv6]

Is there a specific db-4 for marine?

[DA BIG ONE]

DB2 can pump enough to make up to 25 bhp per cylinder, pump pressure 6.7k, 5k rpm limit

DB4 can make up to 40 bhp per cylinder, pump pressure 10.0k, 5k rpm limit.

Both pumps come in configurations up to 8 cylinders.

[quickv6]

So basically the DB-4 maximum fuel delivery is 320HP. So the DS-4 on my truck can deliver the same as the marine version? With all that being said the 6.5 is somewhat pump limited to a maximum HP of around 300-320. I do understand there are mechanical limitations that make it unsafe to do anyway. How do I get maximum fuel delivery from my DS-4? Is this done simply by a chip (94 hd truck)?

[Robyn]

The DB2 is the standard mechanical IP used on 6.2 and early 6.5 engines.
The DB4 is a different pump and has been used by aftermarket builders to make some heavy power.

Quick

Your 94 has a "DS4" these are the electronic IP's used from 94 on to present date.
The DS4 is usually set with the chip to provide around 65-70 mm of fuel.
With an aftermarket chip you can run the DS4 up to 91mm fuel delivery.

I am told that this is tops on the DS4 but I suspect that the outlaws out in the aftermarket can easily modify these to deliver more fuel.

I have my 95 dually set up with a performance chip and its doing a fine job.

The "reported" power with the complete package I have installed is 275+ to the rear wheels.
I have not had the beast on a chassis dyno so I will just let it be what it is. One thing is for sure though it is very snorty and hauls a trailer that weighs 7K very well.

Smoking the duals is an easy task and I would say that breaking stuff could also be arranged if one got stupid with the skinny pedal.

Keep your DB2 DB4 and DS4 tech all in order. Too many confusing numbers.

There are a lot of different Db's and Ds's out there and they all had different specs for different applications.
If you tray swapping a DS4 from one truck to another there can be issues.
The pump has to be compatible with the chip and or the chip has to be changed so all the little creatures will play well together.
The wrong combination can yield some really wierd issues.

The 5068 pump was common as the HD unit in 94 the 5521 is common in the 95 and later trucks, but again there are many depending on the application and emission requirements.

Hope this clears the fog some

Robyn

[Robyn]

Just a note here.
Straight off the Stanadyne specs sheet

DB2 IP rated for 25 BHP per cylinder at 6700 PSI output pressure
DB4 IP rated for 40BHP per cylinder at 10,000 PSI output pressure
DS4 IP rated at 25BHP per cylinder at 13,000 PSI output pressure

These are factory numbers and I know for fact that the rated power on a 6.5 with a DS4 can easily be pushed way past these numbers with the simple addition of a chip and other goodies.

Just some interesting materials though

Seems that a DB4 with good injectors would really be a nice addition to a 6.5 in a non electronic truck.

Good wategate controls and some huge exhaust should produce some fine power.

Lots of heat too :eek:

Later

Robyn

[DA BIG ONE]

There is a waterless coolant listed on Amsoil site and its billed to allow cooling of overpowered diesel beasts thinking this would be a must along w/updates to newer cooling systems on older 6.5's.

Perhaps, compound turbocharging would be needed too for a DB4 powered street beast.

[quickv6]

Thanks for the info Robyn.

[JohnC]

Didn't the DP Power Project engine use a marine pump? Was it a DB4? I don't remember...

the DS4 is limited by the bore and stroke of the plungers. Most of the "hotrod" DS4's employ the cam ring from the early (5068?) HD pump, which increases the stroke. Many have discussed "boring" the thing, but I don't know if it's been done successfully.

[rustyk]

I have a DB-4 and hi-pop injectors on my motorhome (GVW 16,000+ lbs.) as well as a -4 turbo. The original turbo (a Borg unit) seemed to work well, but it failed. The replacement has provided as much more useable power as the original did over the stock engine. The original was, in a nutshell, not spooling up as it should have.

Now note that StaRV II has a Peninsular AMG engine with the 18.1:1 compression. I don't know that I'd want to run the DB-4/-4 turbo combo on a stock engine with its 21+:1 ratio.

[More Power]

Didn't the DP Power Project engine use a marine pump? Was it a DB4? I don't remember...

the DS4 is limited by the bore and stroke of the plungers. Most of the "hotrod" DS4's employ the cam ring from the early (5068?) HD pump, which increases the stroke. Many have discussed "boring" the thing, but I don't know if it's been done successfully.

Nope it was a DB2. The break, according to Peninsular a few years ago, was 320 FWHP. Above that, they used a DB4, below a DB2. Last year, I asked the same question, and Matt told me they prefer to use the DB2 - didn't say why.

After talking to those who have extensive chassis dyno time with a performance-built electronic 6.5, the stock DS can deliver enough fuel with the right programming and the right turbocharger, to push 250-260 RW (the stock LB7 Duramax produced 240-250 RW). It'd be hard to do without the right turbo and an intercooler. Most performance-oriented DS 6.5's with the factory turbo top out at about 200 RW.

Here's the chassis dyno results that show what the 6.5 & Duramax trucks produced at BD's shop during the 2002 Rendezvous in British Columbia, Canada.

http://www.thedieselpageforums.com/photopost/data/500/bd06.jpg

Jim

[JeepSJ]

DB2 IP rated for 25 BHP per cylinder at 6700 PSI output pressure
DB4 IP rated for 40BHP per cylinder at 10,000 PSI output pressure


Hmm. That almost makes me want to pull of my 4911 and find a DB4 and a bigger turbo to feed it.

Still, I find it hard to believe that my db2-4911 is never going to allow me to make more than 200hp, or is that just the out-of-the-box setting?

[rustyk]

My Peninsular AMG setup is rated at 230 HP and 410 lb.-ft. torque @2600 RPM. With the new turbo, which works as it should, all that power is available, and I can scorch the typical 41' Beaver with the 400 HP Cat C9...not that I would, of course...but at 16K lbs. vs my friend's 28K lb. Beaver with something like 1400 lb.-ft., he disappears in my rear-view mirror...

[DA BIG ONE]

Hmm. That almost makes me want to pull of my 4911 and find a DB4 and a bigger turbo to feed it.

Still, I find it hard to believe that my db2-4911 is never going to allow me to make more than 200hp, or is that just the out-of-the-box setting?

DB2/DB4 ratings are factory w/o tinkering throw in turbo, hi-pops, HD cooling, freeflow intake/exhaust and good drivetrain and smiles begin to take hold.

As for max output of DB4 in street application perhaps compound turbos, big IC, copper head gaskets, low CR along lots of cooling capacity would make for some serious power. However, knowing the 6.5 weakness under low power outputs perhaps a waste of $$$$ to think of DB4 for street!