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Max Sluiter
 
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Join Date: Mar 2006
Location: So Cal
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Quote:
Originally Posted by sammyg2 View Post
A V-4?

giggle.

When I first read about these cars I was saying to myself, why in the heck would anyone try making a V-4 again?
It's inherently a bad design. Lots of strange harmonics and forces that can't be completely balanced out and can only be partially dampened.
Kinda like strapping two harley motors together and see which one shakes the other apart first.
I wondered how they could keep an engine like that alive for 24 hours.

A 90 degree V8 is inherently flawed but can work well if balanced and dampened well.
A 90 degree V6 is worse.
An inline six is sooooo much better from a balance and force and vibration standpoint, and a flat 6 is better than that.

An inline 4 is OK, a flat 4 is better, a V-4 just flat out sux from a vibration dynamics standpoint.

Can it be done? Sure can. Can it work? Yep, to a certain extent. Are there better designs out out there? Hundreds of them.



(I've got level 1 and level 2 vibration analysis certifications from Emerson/CSI. Level 1 and level 2 vibration analysis certifications from Entek/Rockwell Automation/IRD. Level 1, 2, and level 3 vibration analysis certifications from the Vibration Institute).

Unfortunately I doan have no certs in photography.


Vibrations aren't the only factor for a racing engine. But Porsche did have to change the spacing of the crank throws to reduce the vibrations that were shaking their hydraulically-interlinked suspension to pieces in their initial design.

Not the first time, the 908 had to go from flat-plane to crossplane to keep the tube frames from cracking. That meant a more complex exhaust though.
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1971 911S, 2.7RS spec MFI engine, suspension mods, lightened
Suspension by Rebel Racing, Serviced by TLG Auto, Brakes by PMB Performance
Old 06-16-2014, 08:08 PM
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