Formula One --- V-8 motor vibration ???

[Fly]

First off, I'm relatively ignorant when it comes to the esoterics of motors. (But I did figure out how to kink the spring on the governor on my Briggs & Stratton 5.75 HP equiped push mower to get the revs up to a more acceptable level.)

I see that F1 is now running V-8s with the exception of a restricted V-10 or 2.

These things are revving to 19,000 or RPM...correct? One of the Speed TV commentators talked about much the V-8s vibrated...I thought the 90 degree? V-8 was a very balanced layout...like a straight 6...does all this go out the window when you're pushing 20,000 RPM?

Whats up...any good (readable) literature and/or websites that anyone's aware of that covers the topic?

Or do I need to go back and read up on rocking couple?

Thanks...hopefully this topic will be of interest.

[DJ Down Under]

I follow Formula One very closely and have not heard anything about vibration problems with the new V8's.

The new V8's are 2.4 ltr and put out about 800 hp and rev to 19,000-20,000 rpm.

The old V10's were 3 ltr and put out about 1000 hp and reved to 18,000-19,000 rpm.

One team is racing the old V10 but have a rev restriction of about 16,000 rpm.

More info on sites like this.. http://newsonf1.net/2006/news/01/jan27w1.htm

In todays race in Malaysia cars were blowing up all over the place..well at least 3 or 4 did....it was very hot..and the engines have to last two races.

In two weeks time they'll be here in Melbourne...I'll be there...and I can't wait.

Here's a pic of the new Williams Cosworth V8 engine.

DJ

http://www.motorsport.com/photos/f1/2006/bah/f1-2006-bah-xp-0025.jpg

[Dallara]

Formula V-8's?

Yes, they do vibrate quite vigorously. Why?

Well, it has nothing to do with the RPM levels. It has to do with crank configuration. In your average street car V-8 you have what is called a "split-crank" or "cross-plane" crankshaft, whereas in a pure racing V-8 you have what is known as a "flat-crank" or "flat-plane" crank.

Take a look at this pic:

http://www.ukcar.com/features/tech/pictures/smooth_v8_crank.jpg

And then look at this page: http://www.autozine.org/technical_school/engine/smooth4.htm


Here's another picture example of a cross-plane crank in a V-8:

http://www.e31.net/pics/V8Cross.jpg

And here's how a cross-plane crank would look from the front:

http://www.e31.net/pics/V8CrossFront.jpg



Here's what a flat-plane V-8 crank looks like:

http://www.e31.net/pics/V8Flat.jpg


And how it would look from the front:

http://www.e31.net/pics/V8FlatFront.jpg


And here's a link to a good primer article on crank configurations of various engines and their "smoothness" qualities: http://www.e31.net/engines_e.html


Flat-cranks are used in racing engines because of far superior intake and exhaust tuning capabilities, hence a flat-crank engine can produce more power... However they are also used because they need literally no counterweights and the crank can be lighter, and hence rev quicker (notice I didn't say to a higher RPM. They just get to that peak RPM quicker due to less rotational inertia).

The trade off is much more vibration with a flat-crank V-8.

The original Cosworth DFV's first seen in the late 1960's in F-1 were notorious for their high vibration levels, but they produced great power from a lightweight engine, and that's what made them the most successful F-1 engine of all time.

So, to answer your question... Yes, the V-8's used now in F-1 do vibrate very vigorously, and yes, it can cause extensive reliability problems - both for the engine and its subsystems, and for even the chassis itself.

Hope this helps, but if you have any more questions, fire away!

Cheers!

Allan (Dallara - NACD)

[Bones]

Much more interesting than the breast implant/reduction explanation as far as I am concerned, but I guess that depends on one's perspective!

Jeff

[BobFV1]

You guys have GOT to see this - better than porn!

http://metacool.typepad.com/metacool/2006/02/unabashed_gearh.html

[Bones]

It is porn, cumshot and all.

[Bones]

So let me ask an idiotic question. Dallara can probably answer this better than anyone. I will embarass myself by doing the asking, but I know damned well there is at least ONE other guy out there wondering this.

What is the deal with revving an engine like that with no load? Is that not a bad thing to do, or is that old urban myth with old engines?


Jeff