[Aaron Quinton]

Those are .050" lift numbers? If so the seat to seat numbers would show more difference which would be more in line with my experience.

Originally Posted by John Langer

286/318 on a 117. Ray, you have to soften up the chambers and reduce compression on the naz compared to n/a. There is a ton you can do with cam profiles.

[John Langer]

What is more important are the .200 numbers...

[Jeff Kinsler]

TE=cgeise;5099949]The gap that used be between N/A and NOS and even Tubo cams has gotten a lot closer over the last few year - at least thats what I have been shown, and by the why, there is a NOS specific Carb - Call Dale Cubic and he can explain it to you as I dont remeber the details. Carry on[/QUOTE]


i have a dale cubic carb, n/a then nos. the only diff was going from q16 fuel to NO2 .

[Aaron Quinton]

Without the lifter acceleration rate the numbers are meaningless. I'm wasting my time on this topic.

The best of luck to everyone pushing the envelop with Pontiac Power!

Originally Posted by John Langer

What is more important are the .200 numbers...

[John Langer]

Wtf does the lifter acceleration have to do with anything. In a real motor the duration is soooooo high that the lifter isn't moving fast. The cam is keeping the valve open a shot ton of time to compensate for the lack of cylinder head. Duration @ 200 is what beat the shot out of my lifters causing me to personally go to jesel to make a lifter that would hold up to the punishment that I was subjecting it to due to the agressive cam profiles and radical spring pressures.

[John Langer]

Lifter acceleration... What about the axial load or side load on the pin and wheel with the agressive lobe lift trying to throw the lifter thru the valve cover and the harmonic vibrations of the conical spring and the 9/16" double taper push rod smacking into the side

[John Langer]

of the casting of the cylinder head due to deflection of a 10.440 rod cycling at a stupid rate of acceleration... Don't get me started on the piston and bearing speeds causing me to spent a ton of time working on oil pan designs...

[Stan Weiss]

Originally Posted by John Langer

Lifter acceleration... What about the axial load or side load on the pin and wheel with the agressive lobe lift trying to throw the lifter thru the valve cover and the harmonic vibrations of the conical spring and the 9/16" double taper push rod smacking into the side

Are you referring to pressure angle?

Stan

[John Langer]

In a Pontiac yes. In a drce 3 or little chief they correct that.

[cgeise]

Originally Posted by Jeff Kinsler

TE=cgeise;5099949]The gap that used be between N/A and NOS and even Tubo cams has gotten a lot closer over the last few year - at least thats what I have been shown, and by the why, there is a NOS specific Carb - Call Dale Cubic and he can explain it to you as I dont remeber the details. Carry on

i have a dale cubic carb, n/a then nos. the only diff was going from q16 fuel to NO2 .[/QUOTE]

All I know is we had him do one for my sons 621 BBC :-( and he said with NOS he would make some mods in the set up to optimize the combo. Not saying it was a bunch -- but it was made a little different.

[Aaron Quinton]

The one's I've seen have a power valve installed so when you hit the N2O and the signal at the carb goes low the fuel is enriched. It reduces lean conditions and detonation at lauch.

[Stan Weiss]

Originally Posted by John Langer

In a Pontiac yes. In a drce 3 or little chief they correct that.

John,
If you have calculated it and can say, just how high is the max pressure angle that you are running?

Stan

[John Langer]

Originally Posted by Stan Weiss

John,
If you have calculated it and can say, just how high is the max pressure angle that you are running?

Stan

It's a simple math calculation if you map the spring pressure vs the angle of the lobe with respect to the wheel of the lifter. You also need to take into consideration the material and diameter of the pin of the lifter wheel. Butt hen again you also have to look at the mean affective cross sectional area of these lifter that is below the lifter bore and angle of deflection of the pushrod on top of the lifter. The only discrepancy will be how much are the lifters offset...

[Stan Weiss]

Originally Posted by John Langer

It's a simple math calculation if you map the spring pressure vs the angle of the lobe with respect to the wheel of the lifter. You also need to take into consideration the material and diameter of the pin of the lifter wheel. Butt hen again you also have to look at the mean affective cross sectional area of these lifter that is below the lifter bore and angle of deflection of the pushrod on top of the lifter. The only discrepancy will be how much are the lifters offset...

John,
The cam design book I have has that covered. Since I did not think you would give me the specific numbers from your engine, I was just asking if you had calculated your Max pressure angle and what it might be.

Stan

[John Langer]

Sorry. I have calculated it...

[LiL Jack]

EHTTFMF!!

[Stan Weiss]

Lil Jack,
It is a week night, just how much have you had to drink?

Originally Posted by LiL Jack

EHTTFMF!!

I would guess that the people from Visner reading this thread are saying WTF did we get ourselves into?

Stan

[Jeff Kinsler]

Originally Posted by Stan Weiss

Lil Jack,
It is a week night, just how much have you had to drink?



I would guess that the people from Visner reading this thread are saying WTF did we get ourselves into?

Stan

no, he isn't saying that. Jack and V.E.D. will have a good relationship!!

[LiL Jack]

Originally Posted by Jeff Kinsler

no, he isn't saying that. Jack and V.E.D. will have a good relationship!!

Yea, he is a cool guy. Even for a Detriot Lions fan!

He is happy he has made the new head and has sold three sets so far.

[LiL Jack]

Originally Posted by Stan Weiss

Lil Jack,
It is a week night, just how much have you had to drink?



I would guess that the people from Visner reading this thread are saying WTF did we get ourselves into?

Stan

E heads are a good cylinder head in the right hands and have proven themselves on the Dragstrip, but some have maxed them out. With the Billet Visner head it is the next logical step for maximum performance.