I stand corrected, and am making a trip to the eye doctor soon...
obviously my eyes need to be recalibrated, as does my butt ;-)
I took the heads, (2 MC, 1 JT) of the shelves, got out the syringe
and measured the cc for both chambers. 30cc for both style
There was a thread asking if a 4kq head would work with an MC
code block (i.e. for 4ktq conversions) allowing the use of the
vacuum pump. It appears that this will work. Also recommended
to swap to the sodium filled valves at that time. As I now find
myself doing this, I'll post up a BTDT in the near future, and after
the motor has some miles on it as well....
Scott, Bruce thanks for the second opinions\confirmations!!
oh yeah, apologies if this comes with MIME... damn Microsoft...
damn company policies...
From: Bruce Bell [SMTP:firstname.lastname@example.org]
Sent: Sunday, January 11, 1998 1:48 AM
To: Hare,Stott (X)
Subject: Re: Volumes and Compression Ratios: Numbers needed...
Well, no BTDT but perhaps some insight on VW/Audi heads.
Early VW 4 cyl. heads had a 25 cc combustion chamber and
later heads (hydraulic) had 30 cc combustion chambers. Oil
an coolant passages changed somewhat between these two
versions. I would expect the Jt head to be like the latter.
Curious you found the MC with a bigger combustion chamber.
I didn't expect that based in intuition. I would have
expected Audi to use the same head castings and different
pistons. Good information, thank you. I'd appreciate
hearing more if you get anything more substantial than I
offered. For what it is worth, my early (1.715 L VW) had
about .040" from the piston top to the deck on the block.
As you may gather I one of those who think Audi and VW
motors are pretty analogous.
> From: Hare,Stott (X) <HAREST@allenbrook.iix.com>
> To: 'email@example.com'
> Subject: Volumes and Compression Ratios: Numbers
> Date: Saturday, January 10, 1998 10:37 AM
Looking for some critical (to me) information.
Has anyone measured the volume of an '86 MC
code lower end?
The volume of the combustion chamber in the MC
Or how about the volume of the combustion
chamber in a 4kq head (JT code motor)??
Tearing my two MC code engines apart and finding
hairline cracks running between the valve seats in
cylinders 1 and 5 on both heads has me admiring
my new paperweights, but in search of a head for
my turbo car.
My thought is, and this has been covered briefly
before, bolt the JT head to the MC block.
Inspection shows both heads have the same
oil/coolant passageways in the same locations
with the same shapes/sizes (and hopefully same
tasks, oops that carries oil, not coolant, doooh!).
I can also verify that the combustion chamber in
the MC code head is deeper, i.e. more volume and
less of a compression ratio. What I need is
something close to help approximate my "new"
volume and compression ratio...
BTDT sought. Anyone who has cc'd any of these
three items (MC cylinder, MC head, JT head) and
could also supply known values the volumes would
be greatly appreciated.
Update on what the results actually are to follow: or
perhaps one track or road, to lead for a while ;-)