how much will .03 raise compression?

and i got an alaniz head from some guy and he included the receipt..
it says "Weld Chambers" and it costed 175.
does that mean the chambers are reshaped? what is the purpose of this exactly..
and does it raise compression?

 

Tell us what head, then tell us the shape of the combustion chamber. With a .030 mill and welded chambers your cr will be real hight with a moderate dome pistons... I run welded 40 cc chambers with a 8.4 cc piston and my cr is 13.8.(87.2 stroke) .020 piston to deck,

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tbone &raquo;</TD></TR><TR><TD CLASS="quote">Tell us what head, then tell us the shape of the combustion chamber. With a .030 mill and welded chambers your cr will be real hight with a moderate dome pistons... I run welded 40 cc chambers with a 8.4 cc piston and my cr is 13.8.(87.2 stroke) .020 piston to deck,</TD></TR></TABLE>
oh yah sorry..
b16 head.

 

Ok now tell us the shape of the chamber , is it round like a b16/itr of is it more oval like a gsr, or is it more shaped like a cloverleaf.
this is my welded up itr head looks like, its the shape of a gsr now.

.

 

I have a JG b16 head that the chambers were welded similar to the gsr. I took the head off and noticed some of the welding on #2 were 'chipping' off or something. I'm sure it can be fixed, but what are some reasons it would do that and would it be safe to throw it on momentarily without encountering problems?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tbone &raquo;</TD></TR><TR><TD CLASS="quote">Ok now tell us the shape of the chamber , is it round like a b16/itr of is it more oval like a gsr, or is it more shaped like a cloverleaf.
this is my welded up itr head looks like, its the shape of a gsr now..</TD></TR></TABLE>

 

i have been told that milling the head that much w/ jdm itr pistons would bring me
to about 11.7:1 compression, instead of about 11.5:1..

anyone wanna input?

 

EVOL (8:05 PM 8/6/2003): weld chambers..what does that mean on my alaniz receipt. i bought a b16 head from a guy who got his head done up by alaniz. does that mean they reshape the chambers for more hp?
SioneSi (1:33 PM 8/7/2003): yes , the stock chambers on the b16 are called hemispherical chambers so in order to get more compression and hp alaniz welded the chambers by adding aluminum and reshaping it , thus becoming a pentroof design chamber. heads that have pentroof chambers are the following, GSR and all the RSX's type s and non type s are pentroof designed chambers. hope this helps

 

those look good. look just like the GSR chambers.

so now you are basically using a GSR head when trying to figure out your compression. so add .2 tenths to that. and then .3 tenths for every thousanth taken off in the milling.

so what ever your normal compression woulda be. ad 1/2 a full point.
and thats a VERY ROUGH estimate.