Don Terrill’s Speed-Talk

blwilliams wrote:Here is a question I have pondered more than once.
Depending on the cam grinding machine wear and tear, how close is the indexing between cylinders?
We degree the cam off of #1 cyl, how close is that IO EC figure on the other 7 cylinders?
If a machine is worn and unable to duplicate from cyl to cyl or even lobe to lobe, that can't be good.
Even if just the lobe separation varies from cyl to cyl, that is going to not be optimal.
Just wondering.

The index plate covers most of the cyl to cyl CL variances, after that it is up to the grinder/operator to change anything beyond the index plate. IIRC the model is made real "journal" size and then turned into a large master... and also IIRC a grinder/person will deadwheel #1 intake vs dowel and based on the core will make changes from there. It is extremely easy to make a mistake during the grinding process when you are doing a "one off".

So, it wasn't to exciting, the Erson cam made for all practical purposes, the same exact power. One other thing, when we dynode it last, we dumped the break in oil, and tried Shafer synthetic 5-50, he swears by the stuff, runs it in everything. It made more power, we didn't do that this time, and it matched peak hp. So, is it possible the Erson cam makes a few more peak hp, I think it does. So, for losing 20-50hp, ahhh, no.

Oh, you rascal you. But thanks for the stimulation of the aging brain cells of mine.

My other hypothesis would have gotten into metallurgical differences between the construction of the cams rather than the numbers. But I'm about as weak on that subject as I am brain surgery.

cstraub wrote: And how one cam company ends up with "new Lobe designs" borrowed from another. I've learned more about integrity in this thread than anything.

I get a few guys mad at me every year, because I refuse to copy someone else's design. Even if it's a design from a company that is no longer in business, I won't do it. I'll study a design, and design something better, but I have no desire to make a copy. that at best, would only be as good as the original. I don't get up in the morning, and go to work, to be "as good" as someone else.

I get a few guys mad at me every year, because I refuse to copy someone else's design. Even if it's a design from a company that is no longer in business, I won't do it. I'll study a design, and design something better, but I have no desire to make a copy. that at best, would only be as good as the original. I don't get up in the morning, and go to work, to be "as good" as someone else.
Mike Jones
Jones Cam Designs
Denver, NC
jonescams@bellsouth.net
http://www.jonescams.com
(704)489-2449

Why I use this guy ^^^^^

I don't know if they did their stuff in house, when I dealt with them in early 2000 they had me contact a guy named Don Johanson for custom cams...I don't know if that was good are bad.

do you happen to know-Is/was this Johanson related to "Howard Johanson" that started Howards Cams?

I like history
Jason

BigBro74 wrote:

I don't know if they did their stuff in house, when I dealt with them in early 2000 they had me contact a guy named Don Johanson for custom cams...I don't know if that was good are bad.

do you happen to know-Is/was this Johanson related to "Howard Johanson" that started Howards Cams?

I like history
Jason

I don't know and the cell # I have for him was not working last I tried. Larry the guy I dealt with at Chet's told me that where most speed junkies have a mill, lath and flow bench in their garage, Don was the first one he ever met with his own cam grinding machine, I found that interesting. I never cam dr one of his cams so I have no idea where he was on quality, on track performance was good although they were not tested against another so they could have been lacking and out of the 5 cams he did for me we never had and valve train issues but these were in the .670 lift range 7500 shift 1/8 mile set ups. I did push them to 8000 but the car was not faster so there was no need.

BTW, I don't know f Larry is still with Herbert racing but Doug is usually easy to get a hold of and he may know...If he is still in business I haven't talked to any of them in years.

CamKing wrote:

cstraub wrote:

I get a few guys mad at me every year, because I refuse to copy someone else's design. Even if it's a design from a company that is no longer in business, I won't do it. I'll study a design, and design something better, but I have no desire to make a copy. that at best, would only be as good as the original. I don't get up in the morning, and go to work, to be "as good" as someone else.

This is the most impressive thing I read in this whole post. This is my thinking as well when it comes to race oriented motors.

Ive often wondered why "cam twist" never enters unto these conversations.
Theres lots involved in twist.

Now theyre even grinding "4 corner" cams for fuel distribution. Decades ago we had different cylinders ground to different lobes. It worked.

I sure miss UDHarold here!

pdq67

CamKing wrote:

cstraub wrote: And how one cam company ends up with "new Lobe designs" borrowed from another. I've learned more about integrity in this thread than anything.

I get a few guys mad at me every year, because I refuse to copy someone else's design. Even if it's a design from a company that is no longer in business, I won't do it. I'll study a design, and design something better, but I have no desire to make a copy. that at best, would only be as good as the original. I don't get up in the morning, and go to work, to be "as good" as someone else.

I like that attitude!!!

UD Harold also once said if the copier didn't know the radius of grinding wheel when original cam was made it would create errors into new master cam

CamKing wrote:

cstraub wrote: And how one cam company ends up with "new Lobe designs" borrowed from another. I've learned more about integrity in this thread than anything.

I get a few guys mad at me every year, because I refuse to copy someone else's design. Even if it's a design from a company that is no longer in business, I won't do it. I'll study a design, and design something better, but I have no desire to make a copy. that at best, would only be as good as the original. I don't get up in the morning, and go to work, to be "as good" as someone else.

Heck, send them over to, "Delta", if I have the name right?

pdq67

HotRodRay wrote:Ive often wondered why "cam twist" never enters unto these conversations.
Theres lots involved in twist.

Now theyre even grinding "4 corner" cams for fuel distribution. Decades ago we had different cylinders ground to different lobes. It worked.

You didn't sell a cam company recently did you?

So I'll admit... I briefly read these posts but looking for a conclusion...

What makes the "one" company's cam out perform the other "possibly" older design?

Speculation?

I think if you actually plotted out the valve lift curve accounting for lash most questions would be answered. A few numbers on a bit of paper can't full define the system