I'm going way out on a limb here, but I wanted yall to critique my
theories, and correct me where I am wrong. So here goes: It seems to me
that a diesel is the perfect engine. It will offer good
horsepower and torque, only lmited by boost pressure, the amount of air
flow into and out of the engine, the rate of fuel delivery, and the
exhaust gas tempuratures. On the other end of the spectrum it is the
perfect economy engine, only limited by running it to lean.
Now, what if you had an engine set up for high performance (ported and
polished head, Larger turbo, high flow injector pump) but simply
adjusted the variables down when you needed economy? Whats more if these
variables could be electricaly adjusted to a pre programed setting
couldn't you adjust it on the fly?
I know banks offers the six gun kit for a 6bt but, in theory wouldn't it
be possible to take a performance modified 4bt from one end of the
spectrum to the other like that? Furthermore how does the 6 gun kit
work on the fuel variable? Are the newer dodges common rail, adjusting
it through pulse width, or the old style mechanical pump adjusting the
rate of flow through line pressure?
Well, these are my thoughts and I decided to throw them out there for
yall to shoot holes through. So tell me what yall think.
Marty Galyean Replied:
If it weren't for the weight increase with the average diesel block per
HP, I'd totally agree.
Both hot rods and economy cars don't like that extra mass. But put a
turbo on it, or find ways to lighten the block (I think titanium alloy
has huge potential for this) and you are right on. Notice all the euro
diesel econo-boxes are turbo'd. A diesel begs for a turbo and a diesel
without one is so heavy per HP that it wouldn't be worth the effort of a
swap for me anyway.
Marty
Gene Climer Replied:
Basically, I think you have it right.
You are also limited by the burn rate of diesel.
You can only get so much rpm out of it.
Indy gassers run up around 20,000 RPM or more.
Gas burns in a flash.
A diesel rod is limited to something well under that.
Diesel burns really sloooooow comparatively.
Banks Racing runs diesels up to 7,000 RPM Redline:
http://www.bankspower.com/twin-turbo-performance.cfm
Let's assume you can run high boost safely.
You've got the right pistons, rings, head gaskets, rods, etc...
And you have enough intercooler capacity to cool the EGTs.
Now, you can dial up or down according to application need.
The 2003 and newer Cummins engines can do exactly that.
They have a new Common Rail system which can be programed on the fly.
That 6-Gun system you mentioned, for example.
That's partly why I went with the ISBe170 version of the 4BT.
It has common rail.
I hope to be able to modify a 2003-6BT control module.
Hopefully, I can get a mfgr to make one special for me.
Then I can dial my boost, fuel, etc, from settings in the cab.
Just need to make sure I don't exceed my "system's ability".
At this point it is not just about the motor, it is a system.
Gino
I Replied:
Does the ISB system have a mechanical fuel pump or electrical feeding
the fuel rail like a gas motor? Does it have a crankshaft positioning
sensor? The reason I ask is because I wonder how hard it would be to
assemble a system like that for a non-ISB 4bt.
Furthermore, how efficient would a de-tuned performance 4bt be?
Gene Climer Replied
Well, you are a little over my head at this point.
By the time you assembled this system, I think you could have bought a new ISBe170.
The ISBe170 has rear gear drive.
This means you can't re-use your front gear drive.
It also means you can't use your rear mount Flywheel housing of choice.
You have to buy new rear flywheel housings to mate to you bell housing.
The list goes on and on like that.
So, I don't think a commonm rail system is very accessible to the older 4BT.
I am not sure, but I think the pistons are a little different also.
Not to mention the turbo.
I have no idea how efficient the system would be when tuned or detuned.
Gene
