purchasing flathead camshafts who do we turn to?

[Pete]

Originally Posted by frnkeore

I have a question for Pete, JWL, Ronnie Roadster or any one else, that might have tried designing their own cams and actually racing them.

How much have you guys experimented with LSA (lobe separation angle) or ICL (intake center line)?

We all know that the 111 LSA has been a standard for the V8 since the beginning of time and varies little for street or race cams. Mostly 110 - 113 are the max deviation. But, how many have advanced (or retarded) the ICL and if so, how much and what was the result?

Advancing the ICL, all other things equal, will always increase the DCR (dynamic compression ratio). That is the actual CR the engine has, after the intake valve closes.

Usually advancing the ICL increases the average torque of the engine but, reduces max HP, by a little but, in drag and circle track, it will lower ET & lap times.

To answer your first question, very little for flathead Fords. There was not a need.
The grinds we use had quite a bit of experimenting before they were put on the market.
On the Ford "60" we retard the cam 3 degrees for the midget engine. This is about the extent of moving the lobes. This is a 333 Boothauser grind.

One cam a team of 4 of us designed was for the Allison unlimited boat engine. It was wet tested extensively for flow on a fixture made from a head. It was also tested for mechanical stability in a fixture made from half an engine and driven by a variable speed electric motor.
We watched the fixture running with a strobe-o-tach which was the equivalent of stop action video of the day. Valve to piston interference was a problem with the high dome pistons we had.
We left the actual testing of the engines to the various boat teams.
After the Allison success, we did the Rolls Merlin and Griffon cams also. Most of the winning teams ran our cams in the late 50's and early 60's.

One thing about cam design back in those days was, there were no computers to do the repetitive work. It all had to be done with slide rules, tape calculators and in our case, limited access to the Boeing analog computer. Digital was yet to come.

There were no CNC machines so master cams had to be generated on a mill with a long list of lift figures.

The bottom line is, some gain can be had for certain applications by moving the lobes in relation to the crank and each other but cost will have to be weighed against the gain.

[Lawrie]

Pete, I worked on a hydroplane here(Agressor) that had a merlin engine ,it was a cool thing to work on, I drove it on the local dam and it was fast, way faster than I felt comfortable, In my youth I had, and still have lots of books and speed records specially the cambells.so I was thinking of them when I drove the hydro.
But that V12 was as noisy as ,you sat right behind it.https://www.youtube.com/watch?v=Y_Fof0CIen0
Lawrie

[Pete]

Originally Posted by Lawrie

Pete, I worked on a hydroplane here(Agressor) that had a merlin engine ,it was a cool thing to work on, I drove it on the local dam and it was fast, way faster than I felt comfortable, In my youth I had, and still have lots of books and speed records specially the cambells.so I was thinking of them when I drove the hydro.
But that V12 was as noisy as ,you sat right behind it.https://www.youtube.com/watch?v=Y_Fof0CIen0
Lawrie

The noise level on our test fixture when it was running at 5300 crank rpm was 115 db. I never knew an engine with no exhaust noise could be so loud.

I never had a ride in an unlimited. After seeing one blow over, I lost interest.
I rode in a 100 mph ski boat once though. Big phun.

[glennpm]

Originally Posted by Pete

To answer your first question ...

Great stuff Pete!

[vilanar]

Very interesting reading.... Thank you all !

[Bored&Stroked]

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Hey Pete . . . am out here in South Dakota at the ranch, working away on some 3D supercharger designs (good fun). Anyway was wondering what your perspective is on the narrow LSAs on all the Harley KR racing flatheads?

I've seen them down in the 90's on quite a few of their most successful grinds. My thinking was that it was done as a part of the huge amount of overlap that they used (BIG duration at .050) and the fact that they ran in a narrow high-rpm power-band. Have you ever looked into these roller cam designs?

[Pete]

Originally Posted by Bored&Stroked

Hey Pete . . . am out here in South Dakota at the ranch, working away on some 3D supercharger designs (good fun). Anyway was wondering what your perspective is on the narrow LSAs on all the Harley KR racing flatheads?

I've seen them down in the 90's on quite a few of their most successful grinds. My thinking was that it was done as a part of the huge amount of overlap that they used (BIG duration at .050) and the fact that they ran in a narrow high-rpm power-band. Have you ever looked into these roller cam designs?

I read about them is all. It amounts to an optimum design for a special purpose in one engine.
In the 60's, Isky did some research with Chrysler cams using lobe separations in the 90's. He advertised them as "5 cycle". This principle was discovered many moons ago and known as the "Milan cooling 5th stroke".

[Ronnieroadster]

Originally Posted by frnkeore

I have a question for Pete, JWL, Ronnie Roadster or any one else, that might have tried designing their own cams and actually racing them.

How much have you guys experimented with LSA (lobe separation angle) or ICL (intake center line)?

We all know that the 111 LSA has been a standard for the V8 since the beginning of time and varies little for street or race cams. Mostly 110 - 113 are the max deviation. But, how many have advanced (or retarded) the ICL and if so, how much and what was the result?

Advancing the ICL, all other things equal, will always increase the DCR (dynamic compression ratio). That is the actual CR the engine has, after the intake valve closes.

Usually advancing the ICL increases the average torque of the engine but, reduces max HP, by a little but, in drag and circle track, it will lower ET & lap times.

My experimentation has been with the ICL I wont go into great detail but I will give one example of results when the locations of the test runs are dramatically different. Running our race car at sea level {1mile} with the cam at 112 ICL resulted in our flathead engine finally running 200 MPH. This same ICL at elevations over 4000 but with a longer distance {3 miles} to accelerate fell flat on its face.
The learning curve has been an interesting adventure the possibility's are limited overall as Pete has written. Its a difficult task difficult changing the ICL with a bolt on gear. Many days I have thought long and hard about designing an adjustable timing cam gear.
When I set a cam in a flathead I'm building be it for my own use of for an engine I build for someone. The cam position is extremely important however we all know almost every one just takes the cam out of the box and installs it as ground. The instructions included with every after market cam tells us to check the cam timing. One recent example I found was a new Isky cam not a regrind that checked out at 119 ICL . Isky's timing specs showed 111. When I was finished installing the cam it was at the 111 ICL
Ronnieroadster

[Fortunateson]

Sorry to be so thick headed...I do know this cam science is not rocket science, it’s way more complicated!

So cam Gurus for a ‘32 5 W with a 255 ci Merc engine with a .030 overbore, Eddie Meyer heads, Fenton intake with either 2 or 3 carbs 97s or 94s, ‘39 Trans, 3.98 (?) rear end, which of the following would be the best carb for fun and drive ability not racing?

Stock Merc, stock EAB, or the apparently despised Max1?

Thanks in advance...

[frnkeore]

Thank you for that, Ronnie. Was the LSA 111°, making it 1° retarded?

[frnkeore]

As light as your car is, I think the Max1, would give you a very noticeable power increase and very little low end lose, over the 8CM cam.

The over lap is 20° (8CM) and 27° (Max1). In your car, I wouldn't be afraid to go up to Pete's 1007B

[21stud]

Originally Posted by frnkeore

I have a question for Pete, JWL, Ronnie Roadster or any one else, that might have tried designing their own cams and actually racing them.

How much have you guys experimented with LSA (lobe separation angle) or ICL (intake center line)?

We all know that the 111 LSA has been a standard for the V8 since the beginning of time and varies little for street or race cams. Mostly 110 - 113 are the max deviation. But, how many have advanced (or retarded) the ICL and if so, how much and what was the result?

Advancing the ICL, all other things equal, will always increase the DCR (dynamic compression ratio). That is the actual CR the engine has, after the intake valve closes.

Usually advancing the ICL increases the average torque of the engine but, reduces max HP, by a little but, in drag and circle track, it will lower ET & lap times.

Generally speaking advancing cam will move powerband to lower rpms and retarding will move it up. ICL is good way to measure timing.

When talking about our ford flatheads, results are well covered in JWL:s excellent book.

LSA changes will give a lot more options but can't be done easily.
have to grind a new cam.. is it worth it? if you got time and money, why not?
might have to do a few of them...

todays car engines got these: varible valve timing in/ex and valve lifts controlled by ECU. good low end and high power when needed. but we all want to do it with our flatheads

Cam designers have decided specs for cam and application it is intended. this is printed to cam card. but is it optimal to your engine and your mix of parts? heads, bore, stroke, comp ratio, exhaust, carbs, ports, chamber shape?

So all talk about best cam is just a talk. but it is interesting

[21stud]

Originally Posted by Bored&Stroked

Hey Pete . . . am out here in South Dakota at the ranch, working away on some 3D supercharger designs (good fun). Anyway was wondering what your perspective is on the narrow LSAs on all the Harley KR racing flatheads?

I've seen them down in the 90's on quite a few of their most successful grinds. My thinking was that it was done as a part of the huge amount of overlap that they used (BIG duration at .050) and the fact that they ran in a narrow high-rpm power-band. Have you ever looked into these roller cam designs?

Dale,
Harley KR cams are sure different than any other flathead cams. roller desing as it is with harleys. yes, very narrow LSA and huge duration.
I believe it worked only with that all out racing, cam started to pull after 4500rpm? heres a pic of one intake cam I have.

[Ronnieroadster]

Originally Posted by frnkeore

Thank you for that, Ronnie. Was the LSA 111°, making it 1° retarded?

Yes in effect I tried it retarded. Now as we know this cam stuff is challenging so I chose to go with the guidance of the cam grinder I was using at the time. After that poor performing experience I have since worked on the ICL experimenting on my own. Our results show there's certainly potential advancing the cam. Now we run over 200 at sea level and at higher elevations with 292 cubes and burning gasoline.
Heck I have also advanced stock cams for certain applications so far the results are favorable. I don't mind the many extra hours it takes to move the cam since I know its worth the effort.
Ronnieroadster

[Bored&Stroked]

I'm with Ronnie on the fact that it is worth the time to first of all degree any CAM - to find out how close the timing events are to the timing card. This is true on ANY engine.

I've seen many aftermarket flathead cams that when installed where quite a ways OFF from the timing tag. Usually this is a result of being ground incorrectly.

In some cases I am able to set the initial advance/retard by redrilling the cam gear on my mill, in other cases the dang cams are way off from the spec. By this I mean the actual timing events and/or LSAs do not match the specified grind. In this case, you cannot 'FIX' the problem with the cam gear - as the cam was ground incorrectly or the masters were off . . . or both. If I see a new cam that is way off in this fashion - I send it back or tell the customer of the situation (no reason for me to have to screw with it as I can't solve the problem).