Originally Posted By: 440Magnum
Originally Posted By: lubricatosaurus
Maybe this just means pushrod V-8's make sense.
Of COURSE pushrod engines "make sense" for passenger cars. The whole idea that they're in any way inferior is just a fabrication of the automotive press who only think in terms of "wow, that's different it must be better," and is a holdover from the 80s. It sure didn't originate with engineers in charge of building on-highway cars.
Pushrods and overhead cams open and close the valves, that's all. Neither one has a distinct advantage below about 7000 RPM, and guess what? Most passenger car engines never go north of 7000 RPM anyway, especially the larger ones. Above that, the lower inertia of an overhead-cam system has an advantage, as does being able to put 4 smaller valves in a cylinder instead of 2 large ones. But if you can stay below 7000 RPM, pushrods win hands-down in terms of compactness of the overall engine, ESPECIALLY V8 and v6 engines. Just compare a Ford Modular to a GM LSx, or a Chrysler Hemi to a Chrysler 4.7 SOHC to see the difference.
I like pushrod engines. But because over head cam is the "new" technology, it get used.
No timing belt. No tensioners. Instead, you get a small cam chain that lasts a long time. And you don't have to start tearing apart stuff on the bottom of the engine to get the head off should that need to happen.
Ironically, I spin my pushrod engine much quicker than the DOHC engine I have
Originally Posted By: lubricatosaurus
Maybe this just means pushrod V-8's make sense.
Of COURSE pushrod engines "make sense" for passenger cars. The whole idea that they're in any way inferior is just a fabrication of the automotive press who only think in terms of "wow, that's different it must be better," and is a holdover from the 80s. It sure didn't originate with engineers in charge of building on-highway cars.
Pushrods and overhead cams open and close the valves, that's all. Neither one has a distinct advantage below about 7000 RPM, and guess what? Most passenger car engines never go north of 7000 RPM anyway, especially the larger ones. Above that, the lower inertia of an overhead-cam system has an advantage, as does being able to put 4 smaller valves in a cylinder instead of 2 large ones. But if you can stay below 7000 RPM, pushrods win hands-down in terms of compactness of the overall engine, ESPECIALLY V8 and v6 engines. Just compare a Ford Modular to a GM LSx, or a Chrysler Hemi to a Chrysler 4.7 SOHC to see the difference.
I like pushrod engines. But because over head cam is the "new" technology, it get used.
No timing belt. No tensioners. Instead, you get a small cam chain that lasts a long time. And you don't have to start tearing apart stuff on the bottom of the engine to get the head off should that need to happen.
Ironically, I spin my pushrod engine much quicker than the DOHC engine I have