Graphite600

Hey guys check this out:

http://forums.gminsidenews.com/showthread.php?t=8375

700ft lbs. stock!?!?!??!?!?!

But they dont know what the cummins can put out!!!

bhoeffner

The cool thing on that is the in regard to the 11.5 rearend. Wonder if it is the same 11.5 AAM we are running? If so it must be able to handle a little more than the 700 ft/lb!

cquestad

My 11.5 sure does...

mattymac

same here.

Barry Smith

they have the same rear end we do.

MonkeyLips

Actually the GM 11.5 has thinner axle tubes (in their current form). The Dodge version is a bit stonger!

I doubt the Duramax alumimum heads could handle 700 ftlbs much longer than the warranty period. I'd say 40-50K before they start warping...those engines can't even come close taking the abuse that the CTD can take.

StrokeThisCTD

bring on any sissy duraminimum.

realsquash

You know, people keep saying that and I've never heard of it happening.

Andy

Got Juice?

Hmm... Let me see.

Juiced since the first prototype 60 HP juice was out.

Over 700lbsft for the last 70K MILES..... I'll Keep my Duraminimum thank you.... it seems that double stacking both timing boxes (double timing advance) works better on duraminimum than Comagainium.

Of course, even compared to the HPCR ISBe the DMX has an advantage in fuel delivery even though we use the same CP3/110 Bosch HP pump.

2 Fuel Rails VS the CTD's 1 Fuel rail. We have more total interior volume than the CTD

I am working on 'divorcing' 1 fuel rail and running dual CP3/110's... enough fuel volume and pressure for (in theory) appx 800RWHP on #2 only (Caveat if we get enough turbo and don't blow apart out connecting rods)

Nothing wrong with an ISUZU motor with ALUMINUM heads. The Processor i used to run with a steyr head (delimbing and bucking trees) used an inline 6 Isuzu Diesel with and aluminum head. That machine would not die and ran 18 hours+ per day for 3 years before overhaul.

Now, maybe we can argue that an I-6 likes aluminum heads more than a V-8? or following your logic a PSD sicksliter is a better engine because of it's iron heads?
Bottom line is that if you DESIGN a diesel from the start to have AL heads on it it will last.

BTW torque production is not totally ROD DEPENDANT! Torque relies on something called BMEP!
Do a google search on that term and read a bit.

That is why water meth adds so well. Changing liquid water to steam takes heat to boil the water hence the EGT reduction.... the extra power is not 100% from the methanol either! (although it does help the burn cycle) The power boost (mainly) comes from raising the BMEP in the cylinder! Changing the liquid water to steam... steam raises the BMEP in the cylinder.

There.... I feel better now

v8440

He's right about a lot of stuff. Some of those duramax's are making a BUNCH of power with only boxes and minor bolt ons. I still feel that the basic engine is less durable than the cummins. The connecting rods he mentions are an example.

Now, I may be wrong here, since I haven't personally looked at the bottom end of a duramax, but if I'm not mistaken, being a v8, a duramax ought to have 5 main bearings. I think I remember that the cummins has 7. Like I said, I might be wrong there, but if I'm not, that would seem to indicate that the cummins has a better-supported crankshaft, which in turn should allow it to safely take a heavier load. Particularly important in a diesel engine, for obvious reasons...

That said, my cousin has an '04 2500 GMC with the duramax. Other than the turbo failing when the truck was 3 days old (probably just a fluke), the truck has been great. I've driven it a few times, and it's nice. The duramax feels much like a gasoline engine. If you want a diesel with gas engine-like mannerisms, the duramax is a good choice.

I happen to like a bit of diesel sound and feel, so I prefer the cummins for that. The duramaxes have not been out long enough to really get a feel for how well they'll hold up, but I suspect they'll last a lot longer than gasoline engines and probably somewhat less than the average cummins.

Steve-l

I think you have this backwards. Torque does not depend on BMEP. BMEP depends on Torque.
To be precise BMEP or Brake Mean Effective Pressure is a term used to express the observed torque in a parameter equivelent to say the amount of steam or air pressure required to create the observed torque. Brake = Torque brake or dynometer, Mean = average, Effective = pressuse applied to piston at the most advantageous crankshaft angle.

Water alcohol injection reduces EGT by adding additional oxygen through super cooling of the air charge increasing the air charge density. The extra oxygen speeds the burn of the injected fuel reducing flaming in the exhaust manifold. Obviously, containing the fuel burn within the clyinder will increase the clyinder pressure and observed torque.
Now you should really feel better,
Steve

Got Juice?

BMEP is a Function of torque.

Take a stock CTD 600 LBS-ft
Raise BMEP by 20%.... by adding a fuelling box. With a Bigger explosion, we have more effective pressure within the cylinder. More Horsepower and Torque. FACT!

Again, google search and re read the engineering papers. I believe you are confusing IMEP with BMEP

Anyhow, in a nutshell, the longer stroke engine is more conducive to torque production becuase of the mean Delta t that the cylinder exerts its maximim preswsure on the piston, thru the rod, to the crankshaft. IF (and it is a big if) a DMX could maintain the same BMEP delta t as a CTD engine at a given level of fuelling we would produce the same torque values.

True there is some oxygen present in Methanol, which, as i stated helps in the burn cycle. Which is why the alcohol acts more as a carrier for the O2 than an actual fuel. Especially considering our temperatures are not hot enough to disassociate the oxygen from the hydrogen in the water.

Pipes

Will the duramax still be around after 14 years of production? unlikely. I am not a deisel genius by any stretch, but the Duramax has something like 600 more moving parts in its motor. The CTD is a simple meat and potatos type engine doing alot more with alot less. (efficency through proper design)Whenever I see emergency deisel generators for buildings, electric deisels in trains, big earth moving machines, they all have inline cylinders, not the V-8 set-up. 700 lbs ft.... my CTD can do that with 350 bucks at the local shop and still be around in 10 yrs. Also the Dodge is a much better looking truck, that GM is just plain ugly.

mattymac

If you ever come out to Cali where it gets a little toasty in the summer months, look me up and we will take a litte joy ride to the chebbie/GM dealerships. Right now I have two friends both with 03 maxes and one at 40 and one at 50K miles, guess what, both heads are being replaced (not from injectors!) but from warping causing them to leak. One guy is so ****** they are denying coveing the motor (this isnt his first issue) so they are just replacing the heads and he isnt very pleased with that. He is so mad at them that they quit working on his truck. Its been sitting there for about 4 weeks now.

Got Juice?

Goodness... we all know a CTD NEVER has had a head failure.

600 more moving parts? I want what you're smoking.

Unless you are counting the needle bearings in the rocker arms as a 'moving' part