ORIGINAL: RLSH700
Okay now I think we have found the route to your problem with the Hemi. You don't like it because its a 2 valve per cylinder pushrod engine. Funny how when you first joined the site, you were bashing the Hemi saying it wasn't a true Hemi, then you want to make it even less like a Hemi by going 4 valves per cylinder. Amusing but not quite as amusing as your response.
That's cool, thanks for remembering me. I'm flattered. First, I don't want to see the new hemi go 4 valves. I don't care much where it goes, I was just correcting the point that 4 valves hurt fuel economy. Second, the 426 is a legendary engine that I've been enamoured with for a long time. There are very few designs in the world that are as impressive. And I love the pushrod setup on that engine. (but I'm not really a fan of cam/poppet valve at all) If this were 1963, the "new" hemi would be an awesome engine. Unfortunately, this is 2007, and in the world of engines, it's just a tad lame. Sorry if that hurts anybody's feelings, but I gotta be me.
ORIGINAL: RLSH700
A little background info for you Blackflag. The 3.5L is based off of the 3.3L. ... If your argument was sound, it would at least be able to maintain the same fuel mileage despite all of this.
Thanks for the background, I'm not that familiar with the large car engines. The problem with your argument, though, is that the 3.5l gets worse fuel economy because ... it has a higher displacement. The 5% difference in displacement just about accounts for your difference in fuel economy. So it's kind of hard to make any determination about the contribution from the 4 valves.
ORIGINAL: RLSH700
How about more examples, the GM 2.3L Quad-Four when 2 valve SOHC 5-speed manual 2.84 axle ratio equipped got around 33 mpg in the earily 90s Grand Am; however, the 4 valve DOHC version only got 30 mpg with the 5-speed manual and 2.84 axle ratio combo. Two examples of a three mpg drop with the same sized engine, both originally OHC designs, same gearing, same transmissions, same car. etc.
The only thing I really know about the quad 4 is that it was supposed to be their "performance" version. See, that's the thing. If you want to put on 4V, then cam it for performance...sure you'll get better performance and worse fuel economy. But that's a tradeoff decision, not the fault of 4V.
ORIGINAL: RLSH700
The problem is there so far no proof of the opposite happening anywhere.
There are plenty of examples, but I can't go dig them up. I think the 1G Neon got the same fuel economy for both engines, which is a tradeoff of fuel economy for better performance. A better place to look is the European engines, where fuel economy is favored. I don't even think you can buy a 2V in Europe - what does that tell you?
The bottom line is this - if you take the same engine, same displacement, same cam, and run it on a dyno with a 2V configuration then a 4V configuration, the 4V is more efficient. This discussion is cool - I do this for a living, so I could talk about it all day - but that point isn't really open to debate. You can find it in a basic book, I think kids in college even learn the point.
[quote]ORIGINAL: RLSH700
Out of all of the different car companies in the world, the last two I would ever use as a benchmarker or one to follow the example of are Mercedes and Ford. The Modular 3 valve engine are not very efficient, nor very powerful despite the modern technology added to them. The Hemi blows the Modular out of the water in terms of power in the truck line and the 6.1L Hemi has more hp per cubic inch than the 4.6L Modular. Do I even have to start on Mercedes? With the exception of their diesels, they are not fuel mileage benchmarkers either. The best they can do with a V8 is 24 mpg and that is with a 7-speed auto with a 2.65 axle ratio (combin