Re: Rocker Arm Ratio
 

They can, and will, check lift at the valve, and then lift at the cam. From that they will check rocker arm ratio. If the ratio is greater than what is in the blueprint specs, they will throw you out.

Feel free to ask Travis Miller, or Dave Ley about this, they will explain it to you. There are also several threads on the subject that explain why and how about rocker ratio. I have seen people thrown out for rocker ratio.

Re: Rocker Arm Ratio
 

Rocker ratio is not constant in the swing of the arc. Check max lift at the valve and at the cam all you want and you will never catch it that way, unless you went crazy and tried to go from something like 1.6 to 1.8

Re: Rocker Arm Ratio
 

If they check lobe lift and x it by the correct ratio it better be the same or damn close to what it checks at the valve, you will always loose some from spring pressure but not the difference between 1.5 and 1.6, but when was the last time they checked lobe lift ? and is that something there doing now ?

Re: Rocker Arm Ratio
 

As per Danny and Bruce at Chicago nationals this year any ratio is allowed.
Dalles Glens corvette had 1.55 rockers from comp cams on his lt1 corvette and 1.5 is the spec .Danny told me all NHRA cares about is that the cam checks
And that is fact.

Re: Rocker Arm Ratio
 

Charley,

Wade O. said Travis checked all the rocker ratio's at Chicago so how could Dallas Glenn be legal with 1.55 rockers when 1.50 are in the blueprint spec.
Travis can you clear this up for the guys going to Indy.

Thanks

Re: Rocker Arm Ratio
 

Get it in writing from Glendora. Email them, and then follow up with a phone call.

Re: Rocker Arm Ratio
 

Alan,

You can use a letter from Glendora for toilet paper. I spent $1000 for a Pontiac carb for my Chevy and have a letter that it's legal but I can't run it. I have another letter from Glendora that says angle adapters for spark plugs are legal and wasted $500 and there not legal.

Re: Rocker Arm Ratio
 

It holds up a little better than their word, or second hand information.

I'm betting Travis will not post any clarification, as NHRA won't want him to. Not to mention they may over rule him on a whim. Which is one of the reasons Wesley Roberson has completely quit.

Re: Rocker Arm Ratio
 

Thanks Alan, I will roll the dice at Indy and if I get thrown out at tear down I will be just another cheater.

Re: Rocker Arm Ratio
 

And folks wonder why people just stop racing, the rules are still not the same across the board. Alan, you are right even tech directors are at a loss when Danny is around.