ok I didn't read the article, too long for me, but did you know the two cars you quoted in the beginning of your article have the same engine? The sebring is the mitsubishi.
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Well I had a 200sx but the GA16DE didn't do it for me even after adding a Hotshot coldair intake so now I've moved up since I have a higher paying job to the satisfying QR25DE. I LOVE NISSAN..... hate the dealer!
You asked for it...
Mr. Huber certainly got in over his head with this subject. Until I saw a link pointing to this article on a Nissan bulletin board, I had no idea your e-mag existed. I wish I was still ignorant of it. I applaud your attempt to assist non-enthusiasts when discussing automobiles but I think Mr. Huber's article nearly rates as a disservice.
For example, Mr. Huber wrote "Overhead valve engine designs are far more traditional. They simply use one intake and one exhaust valve (instead of two and two) that open and close based on the set revolutions of the engine." ALL cam operations are based on set revolutions of the engine, regardless of cam location or number of valves. Destruction of the engine would be nigh instantaneous if it weren't.
Next, "They consider less information and provide inferior breathing capacity." Huh? What does the phrase "They consider less information" mean? As for breathing capacity, any two-valve head will have inferior breathing capacity versus a 3-valve or 4-valve head regardless of cam location. He goes on to call the GM 3800 OHV V-6 "horribly antiquated". True, it is based on an old design, but is a very modern rendition of traditional engineering.
In the single overhead cam section, he writes "The advantage [of OHC vs OHV] is that more ??????" What is this supposed to mean? The author doesn't know of any advantage? He used question marks as a place holder while writing the article and forgot to replace them with his intended words?
His next sentence reads "Unfortunately, valves can be employed and breathing is more precise than OHV designs." This makes zero sense. I will assume this is a typographical error that should have been caught by the editors.
"Unfortunately, because DOHC engines have twice as many intake and exhaust valves as a SOHC motor, they run cooler and more smoothly, quietly, and efficiently." I think the author would be clearer if he wrote, "Unfortunately, because SOHC engines have half as many intake and exhaust valves as a DOHC motor, they run hotter and less smoothly, quietly and efficiently." This is also a point where I feel Mr. Huber is not up to the task as he completely ignored three-valve engines and said nothing about cam lobe differences and valvetrain weight and harmonics between these engine designs that make a significant impact on performance and efficiency. I am aware his audience would have little understanding of the nuances but to completely ignore these aspects leads to a misrepresentation of the respective designs and their purposes.
When he considers reasons for buying either OHC or OHV engines, he notes that OHV engines have more low-end torque. He overlooks the fact that these torquey OHV engines are generally quite a bit larger than OHC engines and that the intended performance amply suits the car's target buyer.
Mr. Huber then lauds Ford's choice of SOHC 4.6-liter engine in the Mustang. That's all well and good, but his next sentences reads "However, the Mustang can feel rather sloppy at the track when paired against the precision of an Acura RSX." Why on Earth is this comparison made? There is no previous mention of the RSX and the comparison itself is apples and oranges. Adding insult to injury, the general tone of the article considers performance as a minor matter to most people, so who would care how the Mustang fairs at the track? Lastly, sloppy feel of a car is not determined by engine choice.
In his concluding paragraph, Mr. Huber opines "Single overhead cam engines are a nice compromise, but they cannot do high-end revs or bottom end torque as well as the other two, respectively." I feel this he is incorrect in claiming that SOHC is lacking in "bottom end torque". This is a function of engine capacity, intake design, cam lobe design and transmission gear ratios rather than any inherent fault of cam location.
Any casual student of the automobile industry will note that domestic manufactures stick with OHV because it's cheaper to produce. Ford issued the SOHC 4.6-liter V-8 as much for advertising purposes as for any efficiency gained by doubling the cams and placing them atop the heads. General Motors had a golden opportunity to step into modern practices when it redesigned the Chevrolet small block for the Corvette several years ago but stuck with OHV for lower cost and tradition. I feel Mr. Huber has written an under-researched article and you spent little time in editing it, giving your audience poor value.
Bruce Hearn
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Bruce in Houston
'94 Nissan Sentra SE-R w/ $tuff, converting to ITA
'98 Suzuki Bandit 1200S w/ $tuff
'02 Dodge Dakota SLT 4-dr tow beast, stock!
Very well put sir. The really nice part is that understood everything you said, the sad part is I may not have caught it all or be able to put quite as you did, had I read the article first.
Hope to meet you soon at another Nissan Houston meet.
BTW whats your take on the jdm stock manifold, not the primera?
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