Valve Job Question

Alan Warman · 12-22-2009, 11:52 PM

I have a question on valve jobs, since they opened up the rules last year. I know you can basically do anything to the valve. My question is what can you do to the seat, like how far can you take the bottom cut into the bowl area. I know you need to watch out and make sure your heads will still pour the cc's. Any input would be welcomed, just looking for the .3 I lost

Alan Warman · 12-23-2009, 11:45 PM

So 324 hits but no info, is it top secret or classified. Or I am just that far off base.

Adger Smith · 12-24-2009, 12:27 AM

Try this: http://www.potseeds.co.uk/highs/no2.html
That might help get the .30 back. :~)

Alan Warman · 12-24-2009, 12:37 AM

Man that's just wrong Adger (LOL). But I did give it try now I am .50 behind and 20lb over weight.

Mike Taylor 3601 · 12-24-2009, 07:25 AM

I was going to reply yesterday but I'm not sure I can answer correctly,I was told you can cut the bowl area down to guide area any angles but I would double check before I did anything.
Mike Taylor 3601

Alan Roehrich · 12-24-2009, 09:04 AM

Everything you do to the valve seat or the bowl must be concentric to the valve guide. There is no written limit as to how deep you can go, or how many angles you can use. Be aware you can cause yourself problems with runner volume on certain heads. And use common sense with regarding to how deep you go, because I don't think they'll go for 5/8" or 3/4" deep and cutting around the valve guide.

bubski · 12-24-2009, 05:32 PM

like alan said any cut and depth concentric to guide. however if cc is not a issue and you have access to a flow bench do some r/d with the bowl hawg and see what happens you may be surprised as you may lose some low .2 .3 numbers and pick up around .4 .45 lift about out of the lift range of a stock cam however the flow bench is not the engine and ive seen some heads bowlhawged to death with horrible low .2 .3 flow # and still run fast . however stock is a free for all now and youre chances of being tossed out of tech slim you have a better chance at getting bounced if youre heads are too stock. merry christmas.

12-22-2009, 11:52 PM	#1
Alan Warman Member Join Date: May 2002 Location: San Angelo Tx Posts: 231 Likes: 0 Liked 0 Times in 0 Posts	Valve Job Question I have a question on valve jobs, since they opened up the rules last year. I know you can basically do anything to the valve. My question is what can you do to the seat, like how far can you take the bottom cut into the bowl area. I know you need to watch out and make sure your heads will still pour the cc's. Any input would be welcomed, just looking for the .3 I lost __________________ Alan Warman STK 4107

12-23-2009, 11:45 PM	#2
Alan Warman Member Join Date: May 2002 Location: San Angelo Tx Posts: 231 Likes: 0 Liked 0 Times in 0 Posts	Re: Valve Job Question So 324 hits but no info, is it top secret or classified. Or I am just that far off base. __________________ Alan Warman STK 4107

12-24-2009, 12:27 AM	#3
Adger Smith VIP Member Join Date: Dec 2001 Location: Texarkana Ark/TX Posts: 2,351 Likes: 435 Liked 678 Times in 262 Posts	Re: Valve Job Question Try this: http://www.potseeds.co.uk/highs/no2.html That might help get the .30 back. :~) __________________ Adger Smith (Former SS)

12-24-2009, 12:37 AM	#4
Alan Warman Member Join Date: May 2002 Location: San Angelo Tx Posts: 231 Likes: 0 Liked 0 Times in 0 Posts	Re: Valve Job Question Man that's just wrong Adger (LOL). But I did give it try now I am .50 behind and 20lb over weight. __________________ Alan Warman STK 4107 Last edited by Alan Warman; 12-24-2009 at 12:40 AM.

12-24-2009, 07:25 AM	#5
Mike Taylor 3601 VIP Member Join Date: Oct 2008 Location: Somerset,Ky Posts: 1,303 Likes: 198 Liked 116 Times in 48 Posts	Re: Valve Job Question I was going to reply yesterday but I'm not sure I can answer correctly,I was told you can cut the bowl area down to guide area any angles but I would double check before I did anything. Mike Taylor 3601

12-24-2009, 09:04 AM	#6
Alan Roehrich VIP Member Join Date: May 2006 Location: Murfreesboro TN Posts: 4,916 Likes: 997 Liked 1,046 Times in 276 Posts	Re: Valve Job Question Everything you do to the valve seat or the bowl must be concentric to the valve guide. There is no written limit as to how deep you can go, or how many angles you can use. Be aware you can cause yourself problems with runner volume on certain heads. And use common sense with regarding to how deep you go, because I don't think they'll go for 5/8" or 3/4" deep and cutting around the valve guide. __________________ Alan Roehrich 212A G/S

12-24-2009, 05:32 PM	#7
bubski Member Join Date: Dec 2009 Posts: 228 Likes: 14 Liked 186 Times in 63 Posts	Re: Valve Job Question like alan said any cut and depth concentric to guide. however if cc is not a issue and you have access to a flow bench do some r/d with the bowl hawg and see what happens you may be surprised as you may lose some low .2 .3 numbers and pick up around .4 .45 lift about out of the lift range of a stock cam however the flow bench is not the engine and ive seen some heads bowlhawged to death with horrible low .2 .3 flow # and still run fast . however stock is a free for all now and youre chances of being tossed out of tech slim you have a better chance at getting bounced if youre heads are too stock. merry christmas.