Valve Diameter Tolerance

Marty Buth · 09-04-2007, 10:17 AM

What is the tolerance on valve diameter from the NHRA apecification?

Bill Harris · 09-04-2007, 10:56 AM

2007 Rule Book Pg 55. "Valve diameter tolerance +0.005" or -0.015" from NHRA specs."

Dwight Southerland · 09-04-2007, 10:58 AM

From the rule book under section Engine:1, Cylinder Heads, "Valve-diameter tolerance: +.005" or -.015" from NHRA Specs." You do have a rule book, don't you?

Marty Buth · 09-04-2007, 12:28 PM

Thanks for the response. That was my memory, but didn't have the rule book handy.

Mike Pearson · 09-04-2007, 01:42 PM

Marty,

Make sure that you check the NHRA specs. They dont always match the OEM valve size. I got tossed for an intake valve that was - 0.016. By Westley of course.

Mike

Marty Buth · 09-04-2007, 02:22 PM

Mike,

Thanks for the heads up. My brother and I both run 2300 ford motors and they are different, even though you can buy a lot of valves that are after market for both years of our cars.

Thanks,
Marty

09-04-2007, 10:17 AM	#1
Marty Buth Member Join Date: Nov 2002 Location: Freeport, IL Posts: 464 Likes: 634 Liked 232 Times in 39 Posts	Valve Diameter Tolerance What is the tolerance on valve diameter from the NHRA apecification? __________________ Marty Buth 3657 STK

09-04-2007, 10:56 AM	#2
Bill Harris Member Join Date: Mar 2002 Location: Ooltewah, TN Posts: 421 Likes: 13 Liked 26 Times in 13 Posts	Re: Valve Diameter Tolerance 2007 Rule Book Pg 55. "Valve diameter tolerance +0.005" or -0.015" from NHRA specs."

09-04-2007, 10:58 AM	#3
Dwight Southerland VIP Member Join Date: Dec 2001 Location: Arkansas - In the middle of everything. Posts: 1,996 Likes: 63 Liked 756 Times in 189 Posts	Re: Valve Diameter Tolerance From the rule book under section Engine:1, Cylinder Heads, "Valve-diameter tolerance: +.005" or -.015" from NHRA Specs." You do have a rule book, don't you?

09-04-2007, 12:28 PM	#4
Marty Buth Member Join Date: Nov 2002 Location: Freeport, IL Posts: 464 Likes: 634 Liked 232 Times in 39 Posts	Re: Valve Diameter Tolerance Thanks for the response. That was my memory, but didn't have the rule book handy. __________________ Marty Buth 3657 STK

09-04-2007, 01:42 PM	#5
Mike Pearson VIP Member Join Date: Mar 2007 Posts: 2,417 Likes: 597 Liked 1,880 Times in 562 Posts	Re: Valve Diameter Tolerance Marty, Make sure that you check the NHRA specs. They dont always match the OEM valve size. I got tossed for an intake valve that was - 0.016. By Westley of course. Mike __________________ Mike Pearson 2485 SS

09-04-2007, 02:22 PM	#6
Marty Buth Member Join Date: Nov 2002 Location: Freeport, IL Posts: 464 Likes: 634 Liked 232 Times in 39 Posts	Re: Valve Diameter Tolerance Mike, Thanks for the heads up. My brother and I both run 2300 ford motors and they are different, even though you can buy a lot of valves that are after market for both years of our cars. Thanks, Marty __________________ Marty Buth 3657 STK