BSI, compression

[aa821@acorn.net (Brian Dettling)]

Demetri:

Your > 200 psi compression readings are excellent.  My 87 16V had about 
those numbers when I bought it with ~12K miles in 1987.  Numbers were 
verified when I had dealer do compression check about 1 year later when 
I found out the 30A fuse for radiator had been blown for some time (it 
was under wtty still).  Dealer cooperated, then charged me like $20 to 
put spark plugs back in (I reasoned they could put new ones back as easily!)


Phillip Mueller/Neil Tovsen posting on BSI stayrod:

FWIW, some Volvos have followed your line of reasoning and use just such 
a strut (not sure if its a shock) to firewall.  As Neil points out, SCCA 
does not allow a strut bar to do more than one function and TSD is 
supposed to go to -body-.  Can someone repost the non Autox link, 
please?  My Java-challenged system does not allow my viddy, even though I 
am member.  Thanks.

"The way I see it:

The engine pivots on the tranny side mount & the engine side mount.  Draw a
line that goes through the center of both mounts (the canter of the rubber
part) & you will wind up with the axis everything pivots on.  This line will
be slightly above the top of the transmission & run kind of diagonally
through the engine compartment.

Now to stop this rotational motion, you will want the mounts in a radial
direction as far from this axis as you can get them.  This is Why VW has one
at the very front & one at the bottom of the tranny.  By mounting this stay
rod to the top of the tranny it is very close to the rotational axis &
therefore has very little mechanical advantage.

I have thought of making a similar 5th mount, but I had been thinking of
running it from the end of the cylinder head to the fire wall.  This way I
would be locating the mount as far from the rotational axis as possible,
giving it maximum mechanical advantage.

Now, the problem I cam up with next is the top of the fire wall would not
have much strength, but since I was going from the top of the engine any
ways, I figured a good way to kill 2 birds with one stone would be to tie it
into an upper stress bar.  What I had bee thinking was to make a sort of 3
point stress bar that ties both towers together & also has some kind of tie
to the fire wall.  Once this is done it would be quite simple to make some
kind of arm that could then be solidly bolted to the head, giving the engine
3 mounts with which to distribute the rotational forces through.

These are just some thoughts that I have had, I haven't actually made
anything yet.  I do agree that any of the above options will greatly
increase noise & vibration entering the cabin, but I was planning on solid
mounts anyways, so what's a little more noise by that point?

=======================================================================
 
Philip P. Mueller III
Westbrook, CT - USA
mailto:philipm3@tiac.net
http://www.p3racing.net


 -- Brian D./OH
How can you be in two places at once when you're not anywhere at all...
Firesign Theatre

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