Re: Thoughts on accepted aftermarket heads for 350?
 

When your done they will pour the same volume. Pass tech, have a great race. That’s why they are welded up. To adjust the runner volume. They will be legal to the inspector.

Re: Thoughts on accepted aftermarket heads for 350?
 

My point is that they originally start at 185 cc and finesse them down to 165 cc where the stock ones are NHRA will know they have been modified thus being illegal. We are not talking about removing material and making it look "stock" adding material is whole different ball game. You never miss what you don't know was there, but when runners are smaller than what the manufacturer is saying it makes you think.
Correct me if I'm wrong but I believe welding and epoxy are illegal in stock, so if you do that to get the cc numbers right aren't you illegal?

Re: Thoughts on accepted aftermarket heads for 350?
 

Sounds like a mystery. The first guy who passes a tech inspection via tear down with these heads, will know the secret. Who ever prepares those heads would get my business if I had a Chevrolet. There are no replacement heads for my combo nor ever will be. I was told “it’s not in the spirit of stock eleminator” There was my answer. This deal is a goldmine for power. I’d work on a set until it passes, and not ask questions on a public forum about it during or after. I don’t have those problems so it
Doesn’t apply to me.


QUOTE=Bobby Lundholm;556815]My point is that they originally start at 185 cc and finesse them down to 165 cc where the stock ones are NHRA will know they have been modified thus being illegal. We are not talking about removing material and making it look "stock" adding material is whole different ball game. You never miss what you don't know was there, but when runners are smaller than what the manufacturer is saying it makes you think.
Correct me if I'm wrong but I believe welding and epoxy are illegal in stock, so if you do that to get the cc numbers right aren't you illegal?[/QUOTE]

Re: Thoughts on accepted aftermarket heads for 350?
 

Wouldn't it be easier for everyone, if NHRA just calls it: Every SBC head must be Less than or equal to 185CC's, have stock diameter valves? Then they just inspect for grinding and pour? We all make a ton of power, and inspection is easy. (FYI, the pinch cross section on the Dart 185cc heads are smaller than the stock intake manifold cross section) Thus, the heads will be a substantial gain once a good valve job and flowing is completed.

Re: Thoughts on accepted aftermarket heads for 350?
 

All I can say is


WTF IS NHRA THINKING....


Maybe they figure that between these BS heads, crate motors and eliminating Heads-Up runs we will all just walk away?????

I have been asking for 15 years what is their Business Plan....

Maybe this is it???

and another thing..

Anybody that knows anything about air flow or a flow bench isn't posting and never will....

Re: Thoughts on accepted aftermarket heads for 350?
 

Hey BG! ;)



Eliminate heads up? Need a really good explanation ...
Are we not a Performance based class?
Combine Auto and Stick? Stick will run away with it. You might think an auto is as fast but a good stick will kick your a $ $. If.... one does not have the negative paper factor in favor.
Have they decided to do away with the Alum Head penalty for all?
Appears the Gov irrigation flow gate is wide open.
Crate motor combos. No- period.

Re: Thoughts on accepted aftermarket heads for 350?
 

All you have to do is look at what the flakes from the IHRA are posting on line.....

They don't even look at wheel studs anymore....

With tech the way it is how far can no heads up be??????

The only thing that could be done is to protest the car, but on the other hand will the NHRA have their people in place to do the inspections????

If and when it happens I'll find something else to do after doing it for 55 years.......

Re: Thoughts on accepted aftermarket heads for 350?
 

So, is it a fact, that the advertised runner volumes on the replacement heads are
acceptable?
In my case, my 624's are to be 168 CC's in/on the intake.
So the aluminum 175 CC's would be accepted??
Terry K

Re: Thoughts on accepted aftermarket heads for 350?
 

Back on topic 350 chevy heads , why would any racer go to all the trouble to approve iron head such as the dart 1070 . You would have to mill intake flange off or valve cover rail to get to 165 .

Re: Thoughts on accepted aftermarket heads for 350?
 

Stock runner must be same size as head it is replacing. According to stock head cc guide sub notes on replacement heads