Re: "Old School" Stocker Cams
 

I have one of Red's deck checkers also,nice looking piece for back when. My friend John Turley gave it to me.
Terry Hindsley

Re: "Old School" Stocker Cams
 

Ed,
Can you post pictures?


Stan

Re: "Old School" Stocker Cams
 

DON was by far ahead of Lunati-cam dynamics ect. Joe Lunati needed my cam to design a flat nose in early 70s mid 70s big block stocker chevy from GK--Don T was the guy!!!

Re: "Old School" Stocker Cams
 

We found an Erson spring in 1.250" diameter that went in at the installed height with 20 pounds too much spring pressure.

On Record Runs or Class Finals the way we fixed that we to put it on the floor a few times on the return road and by the time we got to teardown they would magically test LEGAL at the installed height...

I think that the Statute of Limitations has run out, at least I hope so.....

Re: "Old School" Stocker Cams
 

We run the old Isky Square Cams that are the same ones
as we ran in the 80s. They were designed Al Etter ( Ken's
Dad RIP) and Don Studley ( Shane's Dad RIP).

We have spent Thousands on Stocker Cams but always
go slower!

These Old School Cams are BRUTAL on the Valvetrain
and we do not recommend them to most people!.

Re: "Old School" Stocker Cams
 

Those old school cams are still used by many. I believe that when Don closed GK, John at Bullet Cams purchased some of the tooling. Cam Dynamics was also ahead of their game with dwell lobes too. Do not know what happened to Cam Dynamics tooling after they were split and acquired by other companies. Glen Steyer's was the man at Crane Cams for Stock Eliminator cams. Glen now has his own camshaft business and still makes some great cams.

With the advent of the spring rule allowing higher spring pressures, it allowed racers to take full advantage of the dwell lobes, called by many, square lobes. As a result, rocker arms and lifters subsequently became the next weakest valvetrain component to fail and as a result, the rule change to allow solid lifters and aftermarket rocker arms.

Those that have access to and pay for Spintron testing, will find and discover they can make more power with less aggressive lobes and less spring pressure.

Reducing reversion before TDC is the key. Earlier intake valve openings allow for higher pressure exhaust gases. The less reversion, the earlier airflow starts after TDC. When camshafts have an optimized area at mid-lift and higher lift, it allows the valve to have more time to fill the cylinder with an air/fuel mixture with higher inertia.

Re: "Old School" Stocker Cams
 

Remember going from a "C.D. 7000+" to a G.K.,it was a brutal valve train experience!!
From getting over 7000rpm to struggle to get it running over 6000 and lots of broken valve train parts,but it was a good thing to learn first hand that higher spring pressures not necessary gave you more trouble as you thought some 30+ years ago, braking parts is not the best way to spend your Racing-money but to find out and learn things that way is what keeps us interested keeping doing this, well for me anyway(nowadays I know that :D ) If it was the driving part I think there are lot better options for that :cool:

p.s.
My experience is the same as Johns about newer Cams,I never found much, with that said I never had or worked on a Stocker "induction system" that benefitted from 8000rpm so I must have some real junk :confused:

Re: "Old School" Stocker Cams
 

Can you please explain how that works?

Thanks,
Stan

Re: "Old School" Stocker Cams
 

When I look back 35 or so years ago when I started doing this stuff with a 283, I remember when Stock meant more stock than I care to think about--OEM or OEM replacement valves, cast OEM pistons, OEM rods, etc. and very close to pure stock heads, it proves we pushed the limits of the laws of physics every time we attempted to do this. It's amazing we never had any fatal engine failures more often than we did. I remember running that very close to original stock engine to nearly 7000 RPM many times. If you stayed in low gear a it too long and you heard the engine putter a bit, it obviously was floating the valves, get it into the next gear ASAP and hope you didn't bend anything or have any portion of the valve train bend or start to break. Then, the cam and spring rule change came in around 1988 or so, add about 800 more RPM to what we were already doing to the same engine combo, add more rear gear, and then note any increase. If we knew then what we know now, it would have terrified us to think of what was going on inside of that motor at 7000+ RPM. The stuff we have now to work with is so much superior to what we had then, it's unbelievable. I'm not bemoaning the departure from the old concept of a "Stock Eliminator"motor,I'm glad that most of the technology since then has resulted in vastly increased engine life as well as power outputs unheard of 35 years or so ago, so I am among the first to embrace technology that will improve the sport. Besides, it's fun to go faster!

Re: "Old School" Stocker Cams
 

In many of the Stock, Super Stock and Comp Eliminator engines I have been involved, one of the typical issues that were common with some of the profiles issue with exhaust reversion. Clues of exhaust reversion were sooty intake manifold plenums and exhaust ports.

It has been a known fact and proven that any valve opening event or lift that takes place prior to TDC will effect the performance of an normally aspirated engine.

The intake event during overlap at BTDC, can expose and contaminate the intake charge with exhaust gas all the way to the TDC event when the piston reverses direction and starts down on the intake stroke. The reduction of reversion improves port velocity and improves cylinder filling.

Many years ago, friend asked for help with his new Comp engine that supposedly made enough power in the dyno to make him top of the class. It did not happened and when the engine was put in a different dyno, it did not make the power claimed by the builder. The problem was reversion. Based on his cylinder head and intake flow data and other details, I had a new camshaft ground with different timing events. The result of both the camshaft change and intake plenum volume change was 89 HP. Moreover, the engine required less timing, and although the cam had more duration, the engine had more PTV clearance with the new cam. After the camshaft change, the intake plenum volume was also reduced and the engine picked up 89 HP with both changes.