2009 NHRA Rules

Mike Fuller · 12-11-2008, 08:22 AM

I received my rulebook yesterday and noticed under the cylinder head paragraph that it now states "any valve job permitted" without the 1/4" below valve seat cut being mentioned. Is this a typo error ? Does anybody have input on this. How about it Travis Miller,can you give us some guidance on this ?

Travis Miller · 12-11-2008, 07:42 PM

Quote:

Originally Posted by Mike Fuller

I received my rulebook yesterday and noticed under the cylinder head paragraph that it now states "any valve job permitted" without the 1/4" below valve seat cut being mentioned. Is this a typo error ? Does anybody have input on this. How about it Travis Miller,can you give us some guidance on this ?

So far the only answer I have gotten when I ask about the 2009 Stock valve job is....."any valve job permitted." I just hope my National Dragster comes tomorrow so I get my new rulebook.

Travis

(Disclaimer: Opinions expressed by me on this forum are exactly that, my opinions.)

JRyan · 12-12-2008, 12:24 AM

I don't know!!! My 2009 Rulebook states on page 104 under CYLINDER HEADS, "Cylinder heads are additionally restricted in that they must retain original-size valves at original angles +/- 1 degree and must be able to hold original head volume per NHRA Specifications." That kinda contradicts their "any valve job accepted" statement on the bottom of the section doesn't it?

In Superstock on page 114 under CYLINDER HEADS, it says, "Valves must retain stock angle; valve-stem angle, +/- 1 degee." Again, toward the bottom of the section, "Any valve job accepted".

I'm mystified? All this stuff was supposedly superceded by NHRA in prior year revisions; the wording under CYLINDER HEADS in both Stock and SS is different in the 2009 rules compared to those of 2008, yet when they revised the CYLINDER HEAD section, they failed to remove the contradictions of their own revisons when writing the 2009 Rulebook. Who proof-reads this s--t? Or doesn't "ANY" really mean "ANY" with respect to original valve/seat angles?

Jerry

Dave Goob Cook · 12-12-2008, 11:23 AM

Jerry, that angle referenced would be the actual valve to deck angle,
I.E.> 23 degree SBC valves must stay within + or - 1 degree, so no relocating the guides or angle milling to roll the valve angle.

The wording would indicate that you cannot alter the area beyond the valve seats, which can now be replaced.

????

The spec used to require that that original valve / seat angles and restricted how many angles you could put on the valves / seats, and the width of the margins and the seat angles.

JRyan · 12-12-2008, 03:05 PM

Dave,

It may be what you think, but the average guy is thinking of valve jobs as valve jobs. Also, the paragraph regarding Superstock references both STOCK ANGLE, and the +/- 1 degree (my second paragraph - quote on page 114), so I believe you're interpretation is incorrect. Yes the valve angle/deck surface relationship will change with angle-milling and NHRA is aware of that, but then they wouldn't need to include "STOCK ANGLE" in that paragraph. It's still a contradiction.

Jerry

Bub Whitaker · 12-12-2008, 03:34 PM

You can't angle mill a head enough to change the valve angle more than a degree or should I say, you can but the head wouldn't be useable... what they don't want you doin is reboreing the guides to change the angle

Dean Feiock · 12-13-2008, 08:42 AM

Quote:

Originally Posted by Mike Fuller

I received my rulebook yesterday and noticed under the cylinder head paragraph that it now states "any valve job permitted" without the 1/4" below valve seat cut being mentioned. Is this a typo error ? Does anybody have input on this. How about it Travis Miller,can you give us some guidance on this ?

The ".250 below the seat rule" was removed from the rule book last January as part of the rule book revisions.
The "for acceptable valve job, see General Regulations 1:2 illustration" was also removed as part of last January's rules revisions.
HOWEVER, the 2008 Rules Revisions have already been removed from the NHRA website, as the 2009 Rules Revisions are up.

Dave Goob Cook · 12-13-2008, 11:56 AM

Quote:

Originally Posted by Bub Whitaker

You can't angle mill a head enough to change the valve angle more than a degree or should I say, you can but the head wouldn't be useable... what they don't want you doin is reboreing the guides to change the angle

Umm, my Pontiac 867 heads are angle milled to 20.5 degrees.....while maintaining the chamber cc's

Woodro Josey · 12-13-2008, 01:24 PM

Bub, you are right on again,,,,,,,i vote for you as Tech Director!!!!!! lol

12-11-2008, 08:22 AM	#1
Mike Fuller Senior Member Join Date: Jun 2007 Posts: 950 Likes: 560 Liked 198 Times in 79 Posts	2009 NHRA Rules I received my rulebook yesterday and noticed under the cylinder head paragraph that it now states "any valve job permitted" without the 1/4" below valve seat cut being mentioned. Is this a typo error ? Does anybody have input on this. How about it Travis Miller,can you give us some guidance on this ? __________________ Mike Fuller 396 STK 3961 SS

12-12-2008, 12:24 AM	#3
JRyan Senior Member Join Date: Apr 2003 Location: Aberdeen SD Posts: 645 Likes: 30 Liked 112 Times in 31 Posts	Re: 2009 NHRA Rules I don't know!!! My 2009 Rulebook states on page 104 under CYLINDER HEADS, "Cylinder heads are additionally restricted in that they must retain original-size valves at original angles +/- 1 degree and must be able to hold original head volume per NHRA Specifications." That kinda contradicts their "any valve job accepted" statement on the bottom of the section doesn't it? In Superstock on page 114 under CYLINDER HEADS, it says, "Valves must retain stock angle; valve-stem angle, +/- 1 degee." Again, toward the bottom of the section, "Any valve job accepted". I'm mystified? All this stuff was supposedly superceded by NHRA in prior year revisions; the wording under CYLINDER HEADS in both Stock and SS is different in the 2009 rules compared to those of 2008, yet when they revised the CYLINDER HEAD section, they failed to remove the contradictions of their own revisons when writing the 2009 Rulebook. Who proof-reads this s--t? Or doesn't "ANY" really mean "ANY" with respect to original valve/seat angles? Jerry

12-12-2008, 11:23 AM	#4
Dave Goob Cook Member Join Date: Dec 2006 Location: Indy Posts: 422 Likes: 0 Liked 0 Times in 0 Posts	Re: 2009 NHRA Rules Jerry, that angle referenced would be the actual valve to deck angle, I.E.> 23 degree SBC valves must stay within + or - 1 degree, so no relocating the guides or angle milling to roll the valve angle. The wording would indicate that you cannot alter the area beyond the valve seats, which can now be replaced. ???? The spec used to require that that original valve / seat angles and restricted how many angles you could put on the valves / seats, and the width of the margins and the seat angles. __________________ "Despite the high cost of living, it remains popular." Dave Cook NHRA N375

12-12-2008, 03:05 PM	#5
JRyan Senior Member Join Date: Apr 2003 Location: Aberdeen SD Posts: 645 Likes: 30 Liked 112 Times in 31 Posts	Re: 2009 NHRA Rules Dave, It may be what you think, but the average guy is thinking of valve jobs as valve jobs. Also, the paragraph regarding Superstock references both STOCK ANGLE, and the +/- 1 degree (my second paragraph - quote on page 114), so I believe you're interpretation is incorrect. Yes the valve angle/deck surface relationship will change with angle-milling and NHRA is aware of that, but then they wouldn't need to include "STOCK ANGLE" in that paragraph. It's still a contradiction. Jerry

12-12-2008, 03:34 PM	#6
Bub Whitaker Member Join Date: Feb 2005 Location: Dayton, MD Posts: 222 Likes: 0 Liked 1 Time in 1 Post	Re: 2009 NHRA Rules You can't angle mill a head enough to change the valve angle more than a degree or should I say, you can but the head wouldn't be useable... what they don't want you doin is reboreing the guides to change the angle

12-13-2008, 01:24 PM	#9
Woodro Josey Senior Member Join Date: Jul 2007 Posts: 805 Likes: 0 Liked 3 Times in 1 Post	Re: 2009 NHRA Rules Bub, you are right on again,,,,,,,i vote for you as Tech Director!!!!!! lol __________________ Woodro Josey 2002 STK