[Shotimes] M3 vs. GSX part 2 (long)

[Donald Mallinson]

The old Chevy "Stovebolt" straight 6 was a super nice motor, 
just not very powerful.

GM, in a moment of clear and innovative thought brought back 
the STovebolt with new features and that motor in my son's 
Trailblazer is a joy to listen to and drive.  Super smooth, 
lots of torque and in a first for factory GM straight six's, 
gobs of power.  This motor is a winner.

Don Mallinson

Ron Nottingham wrote:
> 60-degree V6 - good balance, in phase (ex. Ford and GM 3.0L "small" V6's)
> 90-degree V6 - out of balance, out of phase (ex. Ford and GM 3.8L "big"
> V6's)
> 60-degree V8 - out of balance, out of phase (Ford SHO V8, Lotus V8)
> 90-degree V8 - good balance, in phase (most all domestic small and big block
> V8's)
> 
> I don't think the flat (horizontally opposed cylinders) engines are the best
> naturally balanced engines.  Ever drive most anything with an I6 or a V12?
> My vote goes to the V12, with the I6 a close 2nd.
> 
> Ron N. - Dalton, GA
> 90 SHO
> 89 325i
> 9? 750iL (driven more V12's lately than anything else :-)
> "It takes a man to suffer ignorance and smile"
> 
> 
> ----- Original Message -----
> From: "Ron Childs" <rbchilds@pacbell.net>
> 
> 
>>As I recall, Buick extended the life of their V6
>>(which is today's GM 3800) by going to the "even fire"
>>crankshaft. I think that many newer engines have
>>offset cranks because of odd cylinder bank angles.
>>
>>As I had mentioned previously, the "even fire" cranks
>>will make the engines smoother because the cylinders
>>fire at even intervals but they will not help with the
>>inherent imbalance cylinder bank angles mismatched
>>with the number of cylinders. Balance shafts do.
>>
>>I think (somebody chime in if I am wrong) that
>>horizontally opposed engines (Porsche, Subaru, etc.)
>>are the best as far as natural balance.
>>
>>-Ron
>>
>>--- BJamesjr@aol.com wrote:
>>
>>>I spotted my 97 Helms manual on the bookshelf so I
>>>did a bit of looking.  The
>>>manual clearly shows offset crank journals on the V8
>>>crankshaft.  I can't
>>>tell if they offset them enough to even out the
>>>firing pulses or not.  I
>>>thought I remembered that GM offset the crank
>>>journals on some of their 90
>>>degree V6's to help with this.
>>>
>>>Also I found a diagram of the front of the engine
>>>that would lead me to
>>>believe that the balance shaft turns at crankshaft
>>>speed.  The only diagrams
>>>I can find that show part of the balance shaft
>>>basically show a shaft with an
>>>eccentric weight on it, sort of like a camshaft with
>>>a single very long lobe
>>>on it.
>>
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