What Is A Valve Job?

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SpyOneUSN

Senior Member
can someone explain to me what exactly a 4 or 5 angle valve job is and what benefits it does? im guessin it has to do wit air and fuel flow. is it worth the money if your building top end? how much do they run if it is?
 
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viciousracing

Guest
the angle job is the angle the valve seats on the cylinder head chamber. it's usually modified to produce good air/fuel flow efficiency.
 
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viciousracing

Guest
what they mean by 4 and 3 is the "DEGREE" they want to shave off the valve seating to modify air/fuel flow.
from what i know but not sure, most b series sit on a 44* angle, and the valve face angle measures out of a 45* angle, a one degree difference. by shaving "4 or 3" degrees off, means shaving the valve seat "4 to 3" degrees out. So the stock angle of 44* would change out to 47 or 48 degrees depending on what you have shaved off. but the valve face angle has to be shaved out to be 1 degree higher than the valve seat. (be sure you have enough valve margin)
 

saturn_boy96

88 C1V1C 53D4N DR1V3R
hey this is what i was told by my machinist. a three anlge valve job takes the usual one andgle on the valve and vale seat and cuts in two new ones- "3 angles". the purpose is to allow smoother air flow.

i drew a pic, i know its retarded.
 

saturn_boy96

88 C1V1C 53D4N DR1V3R
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by the way i heard that almost all hondas already have a mild 3 angle job from the factory.
 

ekPhred

Senior Member
yes, i also heard that from the factory they put a 3 angle job on it as well.
 

machine

Banned
Originally posted by saturn_boy96@Mar 20 2003, 12:18 PM
hey this is what i was told by my machinist. a three anlge valve job takes the usual one andgle on the valve and vale seat and cuts in two new ones- "3 angles". the purpose is to allow smoother air flow.

i drew a pic, i know its retarded.

i do believe hes got it!
 

saturn_boy96

88 C1V1C 53D4N DR1V3R
usually the valves have the same angles cut into them and then they are "lapped" to the valve seat. lapping allows a total seal in the combustion chamber.
 
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viciousracing

Guest
SATURN BOY----> it is not lapped to the same degree, the seat is 44 degrees while the valve is 45 degrees, it has a 1 degree difference.
 

saturn_boy96

88 C1V1C 53D4N DR1V3R
who told you that, i just want to know for my own knowledge. have you lapped vales before? i don't think the difference could be measured.
 
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