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Old 03-07-2018, 11:04 PM   #1
pbishop
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Default Why Use 'B' Camshaft?

What advantage would switching to a 'B' camshaft give me?
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Old 03-08-2018, 12:00 AM   #2
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Default Re: Why Use 'B' Camshaft?

If all else is left untouched, not much.
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Old 03-08-2018, 12:29 AM   #3
Kurt in NJ
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Default Re: Why Use 'B' Camshaft?

on my car the original cam it got no more than 18 mpg, and no faster than 53 mph, then used unworn "B" cam, valve seats to get valve in proper heigth instead of sunk in the block---67 mph, 23 mpg at 65, I can't say how much the valve seat added, but the car is totally different, ----this is a real "B" cam ,not regrind
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Old 03-08-2018, 01:19 AM   #4
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Default Re: Why Use 'B' Camshaft?

Compared to a stock A cam, the B cam had a slightly longer duration (degrees of cam rotation that the valve is open) and had a little higher lift (valves open a bit more). So the engine can breathe a bit better with a B cam. You get a bit more power with this setup.
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Last edited by Jim/TX/GA; 03-08-2018 at 08:46 AM.
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Old 03-08-2018, 07:06 AM   #5
Kevin in NJ
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Default Re: Why Use 'B' Camshaft?

It should be noted if you intend to switch to a B cam you also must change to wider head tappets.
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Old 03-08-2018, 12:27 PM   #6
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Default Re: Why Use 'B' Camshaft?

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Quote:
Originally Posted by Synchro909 View Post
If all else is left untouched, not much.
I agree . If the B cam is used with the Model B (C) head , Larger B size ports , model B carb. and intake manifold , you should get about a 10 horsepower increase . The C head gave the B engine nearly 7 horsepower . The other mentioned B parts gave a little better than three horsepower. See the Piranio's dyno tests. Don't expect to feel any real seat of the pants improvement if only the B cam is used by its self
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Old 03-08-2018, 12:48 PM   #7
Purdy Swoft
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Default Re: Why Use 'B' Camshaft?

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Originally Posted by Kevin in NJ View Post
It should be noted if you intend to switch to a B cam you also must change to wider head tappets.
An even more important consideration is that original model B lifters were LONGER than model A lifters . If a model B cam is uced , it will be necessary to either use modern longer stem valves or adjustable lifters or the valve stems will not meet the lifters for adjustment. In other words there will be a large gap between the valve stem and the lifter .
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Old 03-08-2018, 12:58 PM   #8
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Default Re: Why Use 'B' Camshaft?

Also in addition to differences mentioned above ... if an original un-reground B cam is used the exhaust valve tappet clearance is 0.022 ... yes 0.007 wider than Model A clearance.

The wider clearance applies only to ORIGINAL Exhaust valve tappets with un-reground camshaft.

If you have a RE-Ground Model B "touring" cam then use the clearances quoted by the cam grinder.

Last edited by Benson; 04-09-2018 at 07:05 PM.
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Old 04-09-2018, 01:16 PM   #9
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Default Re: Why Use 'B' Camshaft?

So, If I want to use a Model B cam in my Model A, can I use the Model B cam followers with Model A valves and springs? I will also be using the Model A Police head ("B" casting mark). Everything else is stock A or aftermarket (Mallory distributor, Ansen single carb intake, Holley 94,).
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Old 04-09-2018, 01:22 PM   #10
Tom Wesenberg
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Default Re: Why Use 'B' Camshaft?

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Originally Posted by brett4christ View Post
So, If I want to use a Model B cam in my Model A, can I use the Model B cam followers with Model A valves and springs? I will also be using the Model A Police head ("B" casting mark). Everything else is stock A or aftermarket (Mallory distributor, Ansen single carb intake, Holley 94,).

Yes, you should use B tappets, or you risk cam and tappet failure.
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