O-boy why did I think this was slowing down

 

oops after looking what I meant to say is any 96' (truck) to any 04' suv with a diesel.

 

You think we can catch up to the most durable engine topic?

 

I thought that it was common knowledge that the Cummins went from a 12v design to a 24v design several years back.

I don't know what anyone would accept as a credible source, but conventional wisdom does dictate that the I6 design is the most inherently balanced design. This made a real difference in the past, but it really does not make any difference now that everything is computer designed with really tight tolerances. Back in the day they made the holes in the block and then made the pistons to fit them, strapped it all to a crank and called it a day. They now take everything into consideration before ever assembling the prototype engine and design accordingly.

I don't throw stones as my house has a lot of glass in it. I am not a mechanical engineer and really don't want to be (although it would be really cool to be able to come up with an idea for something and be able to design it to where it would work).

 

On a stroke of genius, someone who works at IH actually figured out how to couneract the natural unbalance of a V design engine, thankfully it was before they came out with the 7.3, because I have never heard anyone on the side of the road saying "Boy, if that'd been balanced like an inline, we wouldn't be a-walkin`." Evidently, there's no clear disadvantage to having a V design, unless the 2% of PSDs that aren't on the road all went down because they were inferior V designs and not balanced as well as the I configuration.
Logical Heretic, you're using flawed logic. If no R&D was put into the engines and you just threw parts together, then you may be right, but technology has advanced so far that auto manufacturers can honestly make a good engine that's a V design, and it will last and be durable. IE the 7.3 PSD. Anyone else ever even heard or read about it having problems due to it being a V block? I haven't either. Now, with OTR tractors, you're right, they use I configurations for one reason, and that reason is because their engines are extremely large compared to light duty pickup truck engines, so it's easier to make an engine in an I configuration and get it balanced and running instead of attempting to make a V design in that size, it wouldn't be as profitable, because it wouldn't be as simple. There's more to a V design than an I design, so an I design is simpler, but then again, so is a bicycle. The OTR industry uses what is cheap to manufacture and will still work. I engines are fine, they do run, and they are durable, but they don't have any major design attributes over a V configuration. Maybe in the 70s, but certainly not now. Yes, the OTR market is different, that's a land where the I configuration rules and EGRs kill engine longevity, but back here in light duty truck world, where we are, V engines work just fine, and sometimes even smoke the competition, no matter how bad that makes you feel.

 

I have a question thats been bugging me Marine Ironman. With all your opinions on the v8 vs I6 and torqueshift vs dodge auto and dodge quality vs ford quality and....and.... and........What could have possibly made you buy a used dodge inline? All your knowledge and your opinions of dodge vs ford quality. Doesn't sound like what I would have bought if I had the opinions you have. I am really not trying to make fun of it or anything but if I had the opinions you have I would most certainly not have bought a Dodge diesel.

 

I'm glad you did, though, MI, it gives you a more in-depth perspective and first-hand comparisons of Dodge vs. Ford.

 

I think he purchased the Cummins when he was "less educated" and before he came to his senses of course. and FordLariat... I laughed like a little girl when I read your "Boy, if that'd been balanced like an inline, we wouldn't be a-walkin`." bit.

 

I think I read in one of his earlier posts that he had driven it 8 months before his powerstroke. I'm not trying to embarrass or flame but just doesn't make sense.

Just one of the many things that don't make sense to us unedekated ladies.

 

They explain all of that xy 6 axis stuff quite clearly in that link. If a v8 did not have counterweights on the crankshaft. It would spin out of balance even if it wasnt firing. Because an v8 is naturally out of balance. V12 is the next place where the forces get friendly. That was my only point. It has to be counterbalanced because it is out of balance.

I have only bought a couple of brand new vehicles but the autos are generally an option. They usually cost more too.

I have to ask. Can you explain why the fluid coupling dampner is a PSD pro?

I am kinda suprised that you didnt know that the dmax and cummins have 4 valves per cylinder. Cummins has had 4 since january of 98. As you would say. Another cummins pro. Though I dont see how it really matters. It just makes higher revving diesels. A place where I dont think we should be heading.

 

A place where I dont think we should be heading.

....hum...I could think that about all 281 posts, in this thread

 

Ladies,

My Dodge is going on 8 YEARS old, not 8 months old. My excursion is 8 months old. My dodge has 2 valves per cylinder.

Heretic, your understanding of the balance on the V is off. If all cylinders go in the same direction, you must counterbalance that. If you slowly start angling those cylinders apart, they start partially off-setting each other, until you get the angle up to 180 degress, where they offset completely (a flat type design). At 90 degrees the offset in kinetic energy is at least partial.

The problem w/ the V6 inparticular is not that there is no offset. Rather, it's figuring out a reasonable firing pattern for the powerstrokes, and what height the pistons should be relative to each other ... when there are an ODD number of pistons on each side. I.e. if two are up on one side and one is up on the other, things get a bit strange to balance.

The V8 does not have this problem, since an even number of cylinders are on each side.

So ... V designs get better cancellation of forces by making the pistons work more opposite of each other. In fact, 1/2 way (90 degrees) is where these designs go. The complete flat engine would be more ideal ... but not practical.

Hit a ball with a hammer: Inline engine reaction
Hit a ball with a hammer on both sides: flat-engine reaction
Hit a ball with a hammer on both sides, but not exactly opposite: v-engine reaction

Coming from two opposite sides is best. Coming at it from one side (top) is worst. Coming from partially offsetting angles is a compromise, but introduces different effects to overcome.

So ... you make technical TRADES. With a V8, you get some bonuses, like the fact that V's are mechanically and inherently capable of spinning fasters (more RPMS). More RPMs without elongating or distorting the components (block, rods, etc) gives you potentially more or higher horsepower.

Since a 5hp lawnmower can produce 600 ft-lbs of torque with the correct intervening gear and time ... we see that the REAL key to an engine is having (a) the highest possible power at (b) the highest RPM range.

The V allows you to get that. Thus a V is going to beat an inline, generally speaking. I'm not a race-car affeciando, but I'll venture a bet that V engines rule in the top-end racing arena. And, but of course, as any good mechanical engineer or physicist should know, or be able to figure out.

I think Chevy has recently started re-introducing inline-6's. This is stupid, despite the fact that tecnology allows even inlines to be better than ever. If you have room for an inline 6, you almost undoubtedly have room for a v8.

Perhaps Dodge will bring back the Slant-6 they used in my day. Heck, they brought back the 2-valve Hemi. The Hemi concept was great for it's day, but technology in head-design has allowed for great designs in today's market, and a Hemi will ultimately lose again with 2 valves. You must get more valves and smarter valves to get better performance. Dodge likes gimmicks, and the Hemi is a gimmick

Marine Ironman

 

As you have pointed out it makes better harmonics the more cylinders you add. Fewer degrees of seperation between powerstrokes. So why not a v10 or a v12? Fuel economy comes to mind and expense to build in the v12s case.

Those papers that were linked said that because of all the weight on the crankshaft of a v8. To balance it. That technically a short stroke inline is capable of higher rpms. I have not seen this in my experience but Ive read it in two separate papers on the subject now. I have spoken with engine builders and they tend to agree. So I went and looked up the redline on a supra. Kinda sporty. redline is at 6800 rpm. This seems to be close to where v8s redlines. I was told a ford 300 could spin 7000 rpm with stock internals because it is a well balanced engine.

Yes it would be advantageous for racing. For towing around a tractor in the back 40 you would like ample low rpm hp. When it gets deep you need that low end torque. Specially if your running a hand shaker.

Yes V 12s and 16s are where its at. 18000 rpm and a 1 inch stroke. High rpm torque wins races. Just think of the gearing.

The difference though would be fuel economy. They have to meet certain standards. The best way to have ample performance and sip the fuel is with the I6. Just ask a trucker. I dont think its a mistake. I think its brave. I hope it works out for them.

I agree that its a gimmick. Im not overly impressed but it has great high rpm torque. And mucho hp. From a racing standpoint its a great engine. How many american made engines make a hp per square inch of displacement? Hemispherical heads tend to quench the combustion. So they use two spark plugs per cylinder. I dont want to know what a tune up costs. Getting a hemi past emissions is not an easy task. From a designers standpoint.

BTW. That was an awesome post. Very much to the point.

 

I agree that it is stupid for sales since the average American has to hear V-8 to buy it. Maybe they are trying to obtain a wider diversity of customers even though the Inline fans are few and far between V-8 fanatics. I didn't look hard, but all I noticed was an I-4 and I-5 option in the Colorado model.

 

Curiosity has either one of you (Marine Ironman, Logical Heritic) taken your yearly vacation …yet.