Yes...look at my post time...you post at 2am after working on a dozen linked 10 sheet spreadsheet files!

 

hahahahahaha! Yes that is true.

 

.030" is common in NASCAR nowdays.
That's also what we ran in the IRL a few years ago.

BTW, don't believe anything Vizard writes.

 

Specifically why is that?

I heard that when some IRL engine folks went "outside" for cam lobe design they found some significantly better valve dynamics and some power. This was a few years ago also. Does that jibe with your experience?


Specifically, why?

 

I think most of Vizards stuff is alright although he has some older cam ideas in some of his books even if he has changed his mind since then. He told me the year before Greg Anderson domination started that he was way up on everybody and indeed he was!

 

I'm the one they went "outside" to.
The GM cam designs never cam within 20hp of my designs.

as for Vizard, David's a nice guy, but he's english.

 

Well, actually is wasn't from you that I heard about the IRL cams. I don't know who you are, but I'm pretty sure that you aren't the guy I heard it from face to face. Perhaps they tried a few "outsiders". Just how sophisticated is your lobe design software? Commercial or proprietary?

As for Vizard, what's being a Brit have to do with anything? There are a few fair-to-middlin' Brits doing engines. I will say that DV writes for an audience that isn't in the top few % of engine folks, but that's where the writing money is. He does know more that he puts in most of his writing which you probably noticed in your one-on-one with him.

So back to my original question to you: Why is .030 to coil bind "common in NASCAR nowdays" ?

 

Real loaded question there huh pops? I "think" you already know why ;-)

Bret

 

Proprietary, and my cams won three Indy 500's during the IRL era. Crower and LSM also made IRL cams that were better then GM's.

I guess you didn't see the little laughing face.
My shop is right down the street from Vizard's house.
I'm making a couple of cams for him right now.

Because the allmighty and powerful Spintron told us so.

BTW, if you want to know who I am, look in March's issue of Circle Track.
There's a little story in there about balancing camshafts.

 

I saw that article! You aren't the guy making distibutor gears and such as well? I know a few guys from the school that have mentioned you as well. Actually I didn't know that GM even ever did any of their own cams on IRL engines?

 

We make a distributor gear to go with our roller cams.
The basic IRL GM engine came with GM cams. Most all the engine builders replaced them with aftermarket cams.

 

Weve played with the 26120s... advertised specs usually arent on

 

I saw that smiley, but I took your "don't believe anything Vizard writes" as serious rather than poking fun.

I think I know some of what was learned from the Spintron. It that something you want to discuss here?
Saw that. Didn't realize it was you.

 

Since NASCAR has been brought up, are beehives used in NASCAR or any class with a serious solid roller cam?

CamKing, do you make .842 solid flat tappet cams for late model and super late model oval cars?

 

David,

At one point some teams used the Big *** Beehives on some restrictor engines in Cup but I know at least once the higher rpm these springs spin at since they are single wound springs ate through the retainers and ended several guys days! A normal double spring doesn't turn as fast since both springs are tying to spin different directions and one wins but not by a lot!

 

We're working on a beehive spring for Hooters Pro Cup. They have to run a steel valve and are limiter to .625" lift.

The majority of the cams I sell are for Flat Tappet circle track classes.
I'll PM you the info from my website.

 

I will add a little bit of insite to the beehives. We did develop the original beehive (the 95's) for the restrictor plate races and had some initial success but your are right about singles springs spinning and eating into the Ti retainers and creating its own set of issues. That did lead into development of much smaller dual spring for plate engines.

You do get great results by running springs very close to solid but you have to have everything set up close so that things dont go into bind and the springs need to have consistent coil bind tolerances