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Re: Gas Prices- At What Point Do You Park It? [message #116489 is a reply to message #116456]

Fri, 25 February 2011 10:59

gordh1

Messages: 332
Registered: February 2011

Karma:

Senior Member

Hi Craig,
Considering the 455 is a cast iron lump that hasn’t really changed in decades and relies on its displacement to do its work, it’s not difficult to find many other engines which have moved forward in leaps and bounds in their technology…after all, they have had decades to make these improvements. What’s a 455 – 7.5 liters correct? It seems a *really* good 455 is making 400 hp or 53 hp per liter. That’s a really good one; I doubt many out there come anywhere close.

Current “modern” engines are now easily exceeding 100 hp / liter, some designs (i.e. motorcycle engines) are doubling that @ 200 hp/liter and they’re still not using all the tricks in one package. Oh, don’t think I’m pondering a motorbike engine in a 12k# motorhome, but it’s just to say the technology is there and it works.

Craig, you seem to have some good savvy with engines (great!) so let’s look at the sum total increase of your percentages? Let’s not forget that those 0.1% increments have been occurring constantly for a couple of decades? Proper multiport fuel injection is known to be a 10% increase in horsepower *and* economy – that was proven when MPFI became commonplace for many engines in the 80s. They downsized the engine’s displacement, improved the economy, yet gave the consumer even more power than they had prior. Manufacturers ran 5 valves per cylinder for quite some time with great success too but that’s fallen back just the same way the V12 engine is now a dinosaur compared to a V10 – and the main reason for performance gain? Reduce the friction. Imagine, you spend millions developing 5 valve heads then realize that the friction caused by that 5th valve doesn’t equal the gain had you left it at 4 bigger valves. Ditto to twin-cam engines – many manufacturers still use DOHCs but others that are really working to get the most out of a given engine have gone back to a SOHC – main reason…friction.

The biggest area of advancement to my understanding has been with metallurgy, specifically in the design of pistons, piston rings and connecting rods, as this is where a lot of work has to be done, done well, and done for a long time between changes. Piston rings and pistons account for incredible amounts of power loss (friction) – so much so that that is why v12s are basically history…knock 2 cylinders off and the 10 remaining can actually make more total output.

100,000 mile intervals between tune-ups or even changing a sparkplug? We all know what the computer or in some cases *computers* have done in regards to maintaining optimal fuel / air mixture ratios, and then look specifically at fuel injection management and the incredible tasks which can now be performed regardless of vehicle location (altitude, barometric pressure, load…) and at an adjustment rate we can’t even imagine.

Compare this technology to a 4 barrel carburetor? That’s apples and oranges Craig – meaning, it’s really just not fair to compare.

Yes, these days the changes made to a modern engine design are becoming perhaps a little less – they’re on the top of the curve so to say, but they’re still being made and I bet there’s hundreds of engines on dynos right now getting the life kicked out of them to try to make things better.

Drag and resistance of the motorhome – well, that’s sort of a constant now isn’t it. I for one would be removing all sorts of ‘shhhtuff’ from my coach (if I had one! Sad

) because I would want to get that resistance down as much as I could. BTW (fyi) we tested a racing motorcycle at Brainerd Minnesota in the late 80’s and picked up 2 mph on their lengthy front straight by cleaning and waxing *all* the body work – an incredible gain for just a couple of hours of elbow grease. Imagine not only the frontal area of the motorhome, but *all the sides and roof*? Sure, air hits the front, but it then drags down the sides, top and no doubt, the undercarriage, so there’s a lot to think of in all those areas. Wink

Transmissions – well Craig, given closer ratios and multiple speeds, they can only make it easier for any engine / engine management system, to select the optimal ratio depending on the load. I’m sure you’ve been stuck behind an older 18 wheeler at a traffic light as the driver rows his way through the multitude of gears to get the thing to speed again? More ratio selection is better, especially as today these are now automatic or semi-automatic. A three speed automatic transmission regardless of the final drive ratio is (speaking honestly) an absolute has-been, sorry.

Ok so, maybe if and when I swap out the original power unit and replace it with something that is rated at 24 mpg in a big heavy European sedan, I’m not going to get 24 mpg, but I am certain it will be an improvement over the 10 mpg that the 455 delivers now. Will it be worth it? Yup. If I could gain a couple of miles per gallon, have the fun of making something interesting and unique, have something that is technologically current and at least making an effort to be environmentally responsible, I’d give it a go without a question.

Perhaps I’m missing the point of the GMC Motorhome and the group? If like certain old cars people want to have them remain “original” in so far as to say, their power plant, I guess I’m in the wrong place?

Thanks Craig!

Gord

p.s. If anyone tolerates motorbikes, here’s a little video which shows the extent some manufacturers (Yamaha in this case, and they develop / build engines for Ford BTW), are currently at so far as getting power from a drop of gasoline. This technology is going hand in hand with automotive engines albeit slowly. Hope you can envision the hours and millions of dollars which have gone in to the *design concepts*, not necessarily the motorbike itself . Smile

http://www.youtube.com/watch?v=nJKkvbsojWI

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		Gas Prices- At What Point Do You Park It? By: philipswanson on Thu, 24 February 2011 09:16
		Re: Gas Prices- At What Point Do You Park It? By: Dennis S on Thu, 24 February 2011 09:26
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: gmcrv1 on Thu, 24 February 2011 09:45
		Re: Gas Prices- At What Point Do You Park It? By: gordh1 on Thu, 24 February 2011 10:03
		Re: Gas Prices- At What Point Do You Park It? By: jhb1 on Thu, 24 February 2011 10:19
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Thu, 24 February 2011 17:46
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Craig Lechowicz on Thu, 24 February 2011 18:28
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: gordh1 on Thu, 24 February 2011 18:31
		Re: Gas Prices- At What Point Do You Park It? By: cbwoodsr on Fri, 25 February 2011 08:39
		Re: Gas Prices- At What Point Do You Park It? By: Jim Galbavy on Fri, 25 February 2011 15:13
		Re: Gas Prices- At What Point Do You Park It? By: Luvn737s on Thu, 24 February 2011 10:18
		Re: Gas Prices- At What Point Do You Park It? By: Larry C on Thu, 24 February 2011 11:06
		Re: Gas Prices- At What Point Do You Park It? By: philipswanson on Thu, 24 February 2011 11:27
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: gmcrv1 on Thu, 24 February 2011 11:48
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Larry C on Fri, 25 February 2011 14:46
		Re: Gas Prices- At What Point Do You Park It? By: mike miller on Thu, 24 February 2011 11:51
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: gmcrv1 on Thu, 24 February 2011 11:58
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: jhb1 on Thu, 24 February 2011 12:30
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Keith V on Thu, 24 February 2011 12:49
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: philipswanson on Wed, 02 March 2011 12:15
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: philipswanson on Wed, 02 March 2011 12:21
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Thu, 24 February 2011 18:12
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: gmcrv1 on Thu, 24 February 2011 23:15
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Fri, 25 February 2011 01:16
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: gmcrv1 on Fri, 25 February 2011 08:53
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: ejuk8em on Thu, 24 February 2011 12:15
		Re: Gas Prices- At What Point Do You Park It? By: lqqkatjon on Thu, 24 February 2011 14:09
		Re: Gas Prices- At What Point Do You Park It? By: carguy on Thu, 24 February 2011 15:41
		Re: Gas Prices- At What Point Do You Park It? By: cbwoodsr on Thu, 24 February 2011 15:43
		Re: Gas Prices- At What Point Do You Park It? By: gordh1 on Thu, 24 February 2011 17:01
		Re: Gas Prices- At What Point Do You Park It? By: Carl S. on Thu, 24 February 2011 19:54
		Re: Gas Prices- At What Point Do You Park It? By: rwbmitiopt@comcast.net on Thu, 24 February 2011 19:56
		Re: Gas Prices- At What Point Do You Park It? By: Carl S. on Thu, 24 February 2011 20:21
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Tim Conway on Thu, 24 February 2011 21:51
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: hnielsen2 on Thu, 24 February 2011 22:13
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Tim Conway on Thu, 24 February 2011 22:22
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Mike Teets on Thu, 24 February 2011 18:10
		Re: Gas Prices- At What Point Do You Park It? By: John Ruff on Thu, 24 February 2011 18:49
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Tim Conway on Thu, 24 February 2011 19:00
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Carl S. on Thu, 24 February 2011 19:46
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Tim Conway on Thu, 24 February 2011 21:56
		Re: Gas Prices- At What Point Do You Park It? By: Carl S. on Thu, 24 February 2011 20:19
		Re: Gas Prices- At What Point Do You Park It? By: gordh1 on Thu, 24 February 2011 21:00
		Re: Gas Prices- At What Point Do You Park It? By: Craig Lechowicz on Thu, 24 February 2011 23:09
		Re: Gas Prices- At What Point Do You Park It? By: gordh1 on Fri, 25 February 2011 10:59
		Re: Gas Prices- At What Point Do You Park It? By: WD0AFQ on Fri, 25 February 2011 11:48
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Fri, 25 February 2011 12:52
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Bob de Kruyff on Wed, 02 March 2011 15:37
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Fri, 25 February 2011 13:19
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: gordh1 on Fri, 25 February 2011 14:04
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: jhb1 on Fri, 25 February 2011 15:14
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Fri, 25 February 2011 15:27
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: gordh1 on Fri, 25 February 2011 15:45
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: jhb1 on Fri, 25 February 2011 16:17
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Fri, 25 February 2011 17:43
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: jhb1 on Fri, 25 February 2011 17:59
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: jhb1 on Fri, 25 February 2011 18:04
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Fri, 25 February 2011 18:19
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: jhb1 on Fri, 25 February 2011 18:33
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Fri, 25 February 2011 19:10
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: jhb1 on Fri, 25 February 2011 19:44
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Fri, 25 February 2011 19:55
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Byron Songer on Fri, 25 February 2011 22:24
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: UziYaH on Fri, 25 February 2011 23:24
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Little Yimmy on Sat, 26 February 2011 08:16
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: mike miller on Fri, 25 February 2011 20:38
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: WayneB on Sat, 26 February 2011 10:43
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Dennis S on Fri, 25 February 2011 15:34
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: gordh1 on Fri, 25 February 2011 15:48
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Dennis S on Fri, 25 February 2011 15:59
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Larry C on Wed, 02 March 2011 17:55
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: jimk on Thu, 24 February 2011 23:13
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: shawnee on Fri, 25 February 2011 07:46
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Larry C on Wed, 02 March 2011 17:58
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Steven Ferguson on Sat, 05 March 2011 09:04
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Sat, 05 March 2011 15:05
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Sat, 05 March 2011 17:08
		Re: Gas Prices- At What Point Do You Park It? By: Craig Lechowicz on Fri, 25 February 2011 13:36
		Re: Gas Prices- At What Point Do You Park It? By: gordh1 on Fri, 25 February 2011 14:26
		Re: Gas Prices- At What Point Do You Park It? By: Larry on Fri, 25 February 2011 16:08
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Fri, 25 February 2011 16:16
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: UziYaH on Fri, 25 February 2011 22:34
		Re: Gas Prices- At What Point Do You Park It? By: mschultz on Sat, 26 February 2011 08:52
		Re: Gas Prices- At What Point Do You Park It? By: Larry C on Wed, 02 March 2011 18:06
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: gmcrv1 on Thu, 03 March 2011 09:28
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: UziYaH on Thu, 03 March 2011 15:27
		Re: Gas Prices- At What Point Do You Park It? By: Hardie Johnson on Sat, 26 February 2011 10:27
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: UziYaH on Sat, 26 February 2011 11:36
		Re: Gas Prices- At What Point Do You Park It? By: Larry C on Sat, 05 March 2011 08:54
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: comcast on Sat, 05 March 2011 08:59
		Re: Gas Prices- At What Point Do You Park It? By: Bob de Kruyff on Wed, 02 March 2011 12:52
		Re: Gas Prices- At What Point Do You Park It? By: philipswanson on Mon, 07 March 2011 21:13
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Mr ERFisher on Mon, 07 March 2011 21:48
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Larry C on Tue, 08 March 2011 07:27
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Mr ERFisher on Tue, 08 March 2011 07:42
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Ray Erspamer on Tue, 08 March 2011 08:04
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Larry C on Tue, 08 March 2011 08:34
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: midlf on Sat, 12 March 2011 16:43
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Larry C on Tue, 08 March 2011 08:33
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: philipswanson on Tue, 08 March 2011 08:47
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: James Hupy on Tue, 08 March 2011 10:58
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Bob de Kruyff on Tue, 08 March 2011 11:10
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Tim Conway on Tue, 08 March 2011 11:18
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Carl S. on Tue, 08 March 2011 11:34
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Dennis S on Tue, 08 March 2011 11:30
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Ray Erspamer on Tue, 08 March 2011 12:28
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: hal kading on Tue, 08 March 2011 14:34
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Larry C on Tue, 08 March 2011 15:43
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Ken Henderson on Tue, 08 March 2011 20:37
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: Larry on Sat, 12 March 2011 18:52
		Re: Gas Prices- At What Point Do You Park It? By: PETEinLongBeach on Tue, 08 March 2011 01:00
		Re: [GMCnet] Gas Prices- At What Point Do You Park It? By: USAussie on Tue, 08 March 2011 03:24
		Re: Gas Prices- At What Point Do You Park It? By: Keith V on Tue, 08 March 2011 07:39
		Re: Gas Prices- At What Point Do You Park It? By: PETEinLongBeach on Wed, 09 March 2011 06:22
		Re: Gas Prices- At What Point Do You Park It? By: cbwoodsr on Tue, 08 March 2011 08:07

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