I read it in some post awhile ago, but yet the search isn't pulling it up.

Anyhow, I was wondering how milling the head affected cam timing?

Does it advance/retard both cams 1 degree?

Does the cam degree change when milling the head more/less?

Thanks!

 

for your engine, every 11 thou milled requires 1 degree advance.

 

Does this apply to B18C5 as well?

Thanks for the help.

 

I want to make sure I understand what you are saying MD:

If it was a deg advance for every .0011", if you removed .0010" with
a resurfacing and then installed a .45mm 2 layer HG, you would be
at:

.70mm
-.35mm
-----
.45mm HG - (.0010 x 27.5= .0275mm) which becomes @ ".42mm with mill"

.70mm
-.42mm
-----
.28mm reduced lets say .33mm for ease of argument, or .012" is this 10 degrees of compensation? .012" / .0011" thats a whole TOOTH on the cam gear!

I believe I was told by T.O.O. in an email that for every .44mm removed there is 1 deg of compensation. hence, starting with .70mm HG and 0,0 cam timing

if you remove .0010" which is @ .03mm
and you install a .45mm 2 layer gasket (-.35)
you are at .38mm removed from the head roughly,
close enough to warrant a deg of advance I would
estimate. The .44mm spec was given to me by
Larry about 3 months ago when I asked the same
question. Yes, this law should stand across the B series
family I would imagine.

Chances are I could be wrong, this just seems a bit
befuddling

 

who said anything about putting in a 2 layer head gasket? Did I miss that on G S R's post?

0.011 in. is 0.28 mm not 0.30 mm.

Can you relate everything to crankshaft degrees?

If TOO is basing it on 0.44mm on every cam tooth that's 17 thou milled for every 2 crankshaft degrees. How can it be true for all Bseries whenthe deck heights are all different? But B18C's I believe havethe same deck height.


[Modified by Michael Delaney, 10:53 AM 9/10/2002]

 

It is not head milling and it is not a B18C1 but installing a 2 layer gasket on my B18C5 retarded both camshaft by approx. 2.5 degrees (5 degrees on the crankshaft).

 

.....why not just use a degree wheel and dial it in?

 

ok I correct myself, as I said I was asking a question. I am cutting through this veil of confusion with a torch and giving you this:

http://www.theoldone.com/components/camgears/

here T.O.O. explains what I was not able to and amplifies what MD was saying erlier. I posted what was said from the page, not from my memory which is safer
anyways. T.O.O.'s own cam gear design allows for gasket and material removal
with keyways to line it up based on this principle.

.012 per degree x 27.5 to convert to mm is .33 per degree mark on a
+10/-10 cam gear. there are 35 teeth on a b series cam cog, 360 degrees
in a circle, 10.28 degrees per tooth.

if you say purchase a spoon 2 layer gasket at .45mm and stock is .70mm
then do the math:

you removed .25 hence you only are 7.5/10ths of a degree advanced dropping
the gasket in. your b series R motor has the same dimensions as a B18C1,
removal of .012" is a rule of thumb based on enginbuilders that know our cars
wether it be a B16, B18 or B20 the cogs are the same size, therefore when you
remove material it is the same across the b series cars. it would be different for
a H or D series I am sure. what cam gear are you running?

if you for instance have a skunk2 gear, you then would advance 1/2 degree mark since it is a +5/-5 gear, which is a 1 degree advance. this should get you past 0,0 a bit but the overlap will stay the same since you are moving the cams the same way.