blufox

whats the the diff between sohc and dohc engines and whats the advantages and disavantages of each

vtechbrain

As far as I know the differences are negligble as far as performance. They are simply different ways to open the valves in overhead systems. When multiple valves per cylinder started in common cars (80's. It had existed in racing and in some early exotics almost half a century before) The usual arangement was to have one cam for intake and one for exhaust (DOHC). SOHC does both jobs. Today, I dont think there is any inherent benefit to one or the other other than packaging geometry for the cylinder head. VTEC can exist in both configurations. The TL has a single cam while iVTEC fours have DOHC. Example, The NSX has DOHC yet the original N had the same horsepower rating as the new TL (they also share displacement).

rets

It's the tough debate for years.

First, read this... http://auto.howstuffworks.com/camshaft2.htm

and, try this... http://www.jag-lovers.org/e-type/perf.html

plus DOHC VTEC & SOHC VTEC
http://auto.howstuffworks.com/framed...whatsvtec.html

svtmike

A lot of people assume SOHC means a single intake and exhaust valve per cylinder, and that to have a multivalve engine you need DOHC. Certainly on the TL's SOHC 24-valve V-6 that isn't the case.

For a multivalve engine like the TL's, it seems that the SOHC configuration is more compact, while at the same time the valve actuation mechanism is more complex (a cam operating rocker arms that operate the valves vs. a cam operating valves directly).

The DOHC configuration trades off packaging for the simpler, more precise valve actuation mechanism.

Given equal levels of mechanical tolerances (for example, two Honda engines), the simpler DOHC mechanism will be more precise, and therefore more appropriate for very high RPM operation (the TL's 7000 RPM redline doesn't qualify as "very high RPM" these days).

Mike

Ken1997TL

DOHC engines are more "rev friendly" and can be tuned more effectively for speed.

SOHC engines are cheaper to manufacture.

The only DOHC V-6 from Honda is the NSX.

vtechbrain

Ken, the iVtec on the RSX is also DOHC.

Chitown-TL

The TSX is also DOHC.

Oops, you said V6 and that's right. Sorry.

vtechbrain

I missed that too! My apologies.

vtec 6300

Don't forget the Civic SI.