Stock versus Performance Cams

[Tinker]

Originally Posted by Ol' Ron

If you had a copy of JWL's book, you'd have the answer. Any cam with longer duration will kill of low end torque. Raising compression will increase torque through the entire RPM range. The engine you have is almost exactly like the one in his book. Getting his book could save you money.

But you are also saying a reground or another cam is not a bad idea. Compression and porting aside.


Certainly buy the book. Ron I see your book and vanpelts. Both a good buy. But I don't see jwl on the vanpelts site??? Nothing wrong with reading.


http://www.vanpeltsales.com/FH_web/f...oksforsale.htm

[flatjack9]

Originally Posted by Fortunateson

So what you are saying is as long as the original springs are in good shape use them, close I could get away with shims?

Would need to check spring pressure at installed height to see if they are in good shape.

[Fortunateson]

Originally Posted by flatjack9

Would need to check spring pressure at installed height to see if they are in good shape.

Yes, that is what I stated. But if they are close use shims? Or use shims if the valves are a wee bit short?

[Tinker]

I'm still unclear why having zephyr springs (60#) is better then a cam? I don't know??? I run zephyrs on my 38 with a ground cam but I see little reason outside of saying and wearing lobes on a stock cam.


https://www.jalopyjournal.com/forum/...prings.836524/


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[Fortunateson]

The cam shop owner when I phoned a few minutes ago says stock springs are ok but some use Lincoln Zephyr springs.

[Tinker]

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Spring pressure is for keeping the valve on the cam lobe. Maybe at high speeds like mentioned before on this thread to remove valve flutter or float.


If you are going with a different performance cam. I say yes for sure.


If you are using the stock cam, I'm not understanding the over performance of the springs. I only say to learn. I'm asking. I don't know.

[Brian]

The springs I use in all my builds with 100% satisfaction, irrespective of cam selection, are 'stock' progressively wound offerings as supplied by numerous dealers. The important thing is that there is no coil bind. My 2c

[Fortunateson]

Originally Posted by Tinker

Spring pressure is for keeping the valve on the cam lobe. Maybe at high speeds like mentioned before on this thread to remove valve flutter or float.


If you are going with a different performance cam. I say yes for sure.


If you are using the stock cam, I'm not understanding the over performance of the springs. I only say to learn. I'm asking. I don't know.

That's the exact same reason I'm asking for help with this project. I'm really just learning myself and invoking the stored knowledge of the "mighty Ford Barn and the HAMB"...

[Tinker]

If you are using a non stock cam go with some better spring pressure. If using the stock cam, I'd say 40-60# is fine. I big lumpy cam is not the ticket always also.

I go back to.. You need to get a little bit of something going to run 3 carbs. Maybe just heads are good. 3 carbs is a lot. As mentioned 1 center main and 2 outer dumps or dummies.




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[Ol' Ron]

The first thing you have to do is determine the operating range of the engine. Learn how to measure spring pressure at installed height. Just guessing what you have or need can be a disaster. once you've have the installed height, make a stop on a drill press and a bathroom scale and measure the pressure . I suggest 50lbs for most cams under 5k. Now if you plan on racing the engine, go with the cam manufactures recommendations.

[Fortunateson]

OL' Ron,

Thanks for the good tech tip. However, I'm letting the machine shop worry about spring height and pressure. I have full confidence in them.

[40cpe]

Originally Posted by Fortunateson

OL' Ron,

Thanks for the good tech tip. However, I'm letting the machine shop worry about spring height and pressure. I have full confidence in them.

This has all been an informative thread, but part of the original post was "will I need different valvesprings if I have my cam reground".

[tubman]

I would think so. However, what springs you should use would be dependant on the characteristics of the cam you will be using.

I recommended "185-G"'s for a MAX-1 clone, because that's what came with my MAX-1 from Iskenderian. I am not in a position to second guess the "Cam Father".

[40cpe]

Point is, he's leaving it to his machine shop to determine spring pressure, height, etc, after asking for opinions here and disregarding information Ol' Ron and others offered.

[tubman]

No disrespect for anyone involved, but this sounds like an uninformed value judgement to me.

[Fortunateson]

Originally Posted by 40cpe

Point is, he's leaving it to his machine shop to determine spring pressure, height, etc, after asking for opinions here and disregarding information Ol' Ron and others offered.

The point really is I'm leaving my machine shop to determine if the stock springs are up to spec. A further point is that I haven't disregarded a single thing as I'm considering all comments, except yours of course, in determining which way to go.... I'm doing research independent of this forum as well and am thinking stock, Zephyr, as well as the Isky springs.

[40cpe]

deleted

[Tinker]

Why again was the question asked??? Cam?

[Fortunateson]

Yes, I was looking for guidance regarding stock versus performance cams. In listening to the pros and cons of both and speaking to my veteran cam grinder I will be going with Shadbolt's M70 ( though I posted M60).

That lead to info required as to valve springs. I read/heard about stock, LZ, and those supplied by Isky. My cam grinder said stock are fine but some go to LZ. I'm not going to be high revving this engine. I'm happy with good low end torque. Higher spring pressure I understand is for high revving and/or radical cams.

But stay tuned as this journey continues...

[Fortunateson]

Anything special about a C1BA cam?