Diesel vs gas......................

[blt2ski]

OK folks, there have been a few to many diesel vs gas threads that have shall we say gone to "Hell and a hand basket"! So if all of you would put in you BEST, no flaming reasons for going gas vs diesel, pro and con, I will either leave your thread, or copy and paste pertinant info to the 4 posts of pro and con of diesel or gas. This can include the GM 8.1 vs Dmax or Ford V-8/10 vs PSD etc too.

Be real and honest in you answers, not hear say, flaming etc PLEASE!

If posts are good ones, I will leave, if inflamatory or trolling in nature, they will be deleted! I will get this stick'd to the top for future parusing for those that need this type of info.

Added 6-23-04

We are getting closer to answers I am looking for etc.

Stuff like Ken's - T-Bone posts are good. There are a few others of you that have not posted, some with a 9 point question and answer type to figure out how you went with one or the other. If you are one of those, PLEASE repost in this thread. I may have to look up whom has done this and PM you, but if you think this is you, you now know what to do.

Also, for those of you with $ per gallon for either fuel right now, I would prefer to see a post with ...."in my area, diesel is typically .10 less than unleaded" then explain your numbers. As currently in the Seattle area, diesel and unleaded are any where from 2.05 -2.30 per gallon, with mid test .10 more and premium about .20 more, with equal high low splits. Two weeks ago those prices were upwards of .30 -.40 per gallon more. people were posting $ per gallon that were for me. "I wish" If someone is reading your post a year from now, they may want to know where your paying 1.65, when the price of fuel is over $3 per gallon. Let's keep prices out of it if possible.

Bert and tin tipi, got into a good discusion on the pros and cons of RPM's, drive train etc. I would prefer to NOT see the quote of the other in responding threads, maybe just write a quick wording of re tranny gearing, instead of the whole 40 words or so in that paragragh, so the repsonse is shorter if possible quicker and easier to read etc.

I have deleted some 15+/- posts, that were off topic etc. Please note, I am trying to keep this at the top, as the ONLY gas/diesel thread in this area. So if one is trying to decide, we do not have to go thru this BS any more. As such, I will be deleting ANY future posts close to resembling this type of topic. I may have to change "this" title to a better one, if one has a better sounding title, to be more positive, better claification, let me know here, or in a PM/e-mail, what ever you feel most comfortible with.

Again thank you for all of you that are keeping responses positive, etc.

Also we could use a few more positive reasons to go gas, as many can see I have both gas and diesel, both have a place! Both have positive reasons to buy that fuel, lets keep the threads etc to that purpose only!

Marty

[Sport45]

ohioviper wrote:
The point is that it is an inferior design , and thus the life span is not what the iron block ,iron head diesels are.End of the story.

Hey! Let me try something like that.

I think you’re mistaken.

Dismissed.

[bluenote]

ohioviper wrote:
I'm not suprised that folks with Chevy D/A in their sig are disagreeing with me. I am suprised that none of you have done anything to disprove me. Only make silly arguments.

You've done almost nothing to "prove" yourself either, just give your obviously biased opinion. There have been far more valid arguments made to disprove you than anything you've said to prove yourself.

Are there D-max trucks blowing heads left and right ? No thats not the point I'm trying to make. The point is that it is an inferior design , and thus the life span is not what the iron block ,iron head diesels are.End of the story.

Again, "inferior design" is your opinion, not in any way, shape, or form proven by your continued posting of your biased opinion. Since there is significantly more evidence to disprove your opinion than what you've offered to prove it, it is an inferior argument...end of story.

[Sport45]

Disprove what? That aluminum is not as strong as iron? Or that aluminum is not strong enough to do the job?

I think we all agree that aluminum is not the same as cast iron. It's softer, expands and contracts more with temperature, and it's much lighter than iron. Where we disagree is whether or not it is a fit material for this service. You won't allow that aluminum can be sucessfully used to build heads for a diesel engine. That's your opinion. Not fact. And not proven by your arguments by any stretch of the imagination. Obviously, people smarter than me have decided that you can indeed build diesel heads out of aluminum. And in thinking about it I see no reason to believe them wrong. Cast iron is in ways inferior to cast or forged steel. That doesn't make cast iron bad, just different.

I should really bow out of this one. I don't have much automotive diesel experience. The last diesel I worked with was a MAN B&W for factory testing in Augsburg. 10,000hp at 1500rpm. I thought it was impressive until I took their factory tour and saw some of the real engines....

[BertP]

ohioviper wrote:
I'm not suprised that folks with Chevy D/A in their sig are disagreeing with me.

The fact that I own a DMax is irrelevant. What you are saying is incorrect and my owning a different truck wouldn't change that.

ohioviper wrote:
I am suprised that none of you have done anything to disprove me.

Are you reading the same thread I am?

ohioviper wrote:
Only make silly arguments. Are there D-max trucks blowing heads left and right ? No thats not the point I'm trying to make.

So, DMax's are not blowing head gaskets left and right - that's what many of us have been saying all along. But, you started by saying that they are.

ohioviper wrote:
The point is that it is an inferior design , and thus the life span is not what the iron block ,iron head diesels are.End of the story.

Then why does the PSD - an iron head on an iron block - have the same life expectancy as the DMax? Again, you are over simplifying the issue. There are many factors in determining the life expectancy of an engine. Whether it has an iron or aluminum head is not one of them.

Bert

[BertP]

ohioviper wrote:
So your trying to tell me a gas engine has more cylinder pressure than a gas now ?

No. You stated "The more compression the more powerful the combustion = more head pressure = more force against the headgaskets." and I used the example of the non-turbo'd 7.3 PSD and the GM 6.0l gasser to show that that statement is incorrect. The 6.0l gasser has higher cylinder pressure than that 7.3. The point is that higher compression does not equal more power.

ohioviper wrote:
The compression ratio, intake manifold pressure (particularly in the case of turbocharged engines), volumetric efficiency, and the timing of ignition (spark) or injection (diesel) events affect the peak cylinder pressure. Some production automotive diesels have peak cylinder pressure in the 190 bar (2800 psi)range.

Good read.

That is all true. I was merely addresseing your claim that higher compression equals higher cylinder pressure. That, by itself, is not true.

Bert

[ohioviper]

I'm not suprised that folks with Chevy D/A in their sig are disagreeing with me. I am suprised that none of you have done anything to disprove me. Only make silly arguments. Are there D-max trucks blowing heads left and right ? No thats not the point I'm trying to make. The point is that it is an inferior design , and thus the life span is not what the iron block ,iron head diesels are.End of the story.

[bluenote]

ohioviper...

You keep saying the aluminum head design of the Duramax is a problem, when anyone with an internet connection (and a non-biased attitude towards their research) can find that to be 100% incorrect. It has proven to be an excellent design. The only problems happening are the ones you are erroneously claiming to have happened. You can argue your opinion until you are blue in the face, but when you make statements that are incorrect, you shouldn't be so surprised people disagree with you.

[Sport45]

There's no question that diesels operate at higer cylinder pressures. BMEP and peak pressures are both higher than for similar gasoline engines. (That's part of the reason diesel engines sound like somebody shaking a jar full of marbles.) What does that have to do with aluminum heads? The engine parts have to be designed to do their job. No more.

When you want to water your yard do you use a hardware store garden hose with a maximum working pressure of about 150psig? Or do you get a stainless braid reinforced flexible metal hose good for 1500 psig? Or do you go for the best and run 20,000psi Chiksan joints hammer-unioned to XXXH schedule pipe since everyone knows it will hold more pressure than the hose? My guess is you get a good quality garden hose because you know it will handle the pressure you need it to.

[ohioviper]

So your trying to tell me a gas engine has more cylinder pressure than a gas now ?

The compression ratio, intake manifold pressure (particularly in the case of turbocharged engines), volumetric efficiency, and the timing of ignition (spark) or injection (diesel) events affect the peak cylinder pressure. Some production automotive diesels have peak cylinder pressure in the 190 bar (2800 psi)range.

Good read.

[TxCoastCamper]

ohioviper wrote:

Makes no difference whether the head is aluminum or iron.

This brings us back to square one. It does make a difference.The aluminum heads can not hold the cylinder pressure,heat cycles,or clamp load that an iron head can. Therefor an aluminum head will infact give up its head gasket seal before an iron head would.

Yep, everyday I drive to work I see 'em! Lots of 'em. Tens of hundreds of thousands of GM Alumi-Irun conglomerations cast aside along the road, all pressure weak and gasket leaking.


:R

[BertP]

ohioviper wrote:

Makes no difference whether the head is aluminum or iron.

This brings us back to square one. It does make a difference.The aluminum heads can not hold the cylinder pressure,heat cycles,or clamp load that an iron head can. Therefor an aluminum head will infact give up its head gasket seal before an iron head would.

The metals don't have to provide the same clamping potential. They just have to provide sufficient clamping force. Titanium can provide a lot more clamping force than cast iron but when is the last time you saw an engine with titanium heads? The aluminum heads can provide all the clamping force necessary in an engine like the DMax, PSD or CTD. The DMax proves that and so to all the other millions of engines out there with aluminum heads - gassers and diesels.

Bert

[BertP]

ohioviper wrote:
That makes absolutely no sense at all.
You might want to rethink that one.The more compression the more powerful the combustion = more head pressure = more force against the headgaskets.

Wow, you're really streching now. In your previous post, you stated that higher compression causes higher cylinder pressure. By itself, it does not because it is much lower than combustion pressure. Now you come back with higher combustion pressure.....

If you would take a moment and consider what you are saying, you would relize that your above statement isn't correct. The non-turbo'd 7.3 PSD had higher compression than a 6.0 gasser, but the gasser has much higher power and, therefore, much higher cylinder pressure. Higher compression by itself does not equal higher power.

You might also want to have a look at aircraft piston engines. All aluminum and they are producing a lot more power in many cases than the diesels we drive.

Bert

[ohioviper]

Makes no difference whether the head is aluminum or iron.

This brings us back to square one. It does make a difference.The aluminum heads can not hold the cylinder pressure,heat cycles,or clamp load that an iron head can. Therefor an aluminum head will infact give up its head gasket seal before an iron head would.

[Sport45]

ohioviper wrote:
The more compression the more powerful the combustion = more head pressure = more force against the headgaskets.

Close. Diesels have a higher BMEP but it's not because of the higher compression ratio. It's just the nature of the beast. Turbocharged gasoline engines have significant BMEP's as well. Torque is a function of cylinder pressure, piston face area, and stroke length.

Makes no difference whether the head is aluminum or iron.

[ohioviper]

Bert P wrote:
The forces of compression are miniscule when compared to the forces of combustion. The fact that a diesel has higher compression than a gasser means nothing when it comes to comparing the stress the head gaskets of the two engines have to endure.

That makes absolutely no sense at all.
You might want to rethink that one.The more compression the more powerful the combustion = more head pressure = more force against the headgaskets.

bluenote wrote:
You keep making the same statements, even though your premise is incorrect and obviously very biased. Give it up while you still have some dignity.

I'm not biased, just stating my opinion. My point of view based on information I have read and experiances I have had.If you feel my premise is incorrect then prove it so.
Sorry my dignity is still intact ,no shame in pointing out what I view as a downfall of a paticular engine design. If you let these comments bother you ,you are taking this stuff way to serious.