Question for auto trans guys with big cam.

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May 21, 2018 | 11:48 AM

Rob 93ZR-1

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From: Fear causes hesitaiton...and hesitation will cause your worst fears to come true. Houston TX

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Question for auto trans guys with big cam.

Did or does the big cam make the brake pedal feel different? I'm trying to figure out if vacuum is my problem. Brake pedal feels numb, or wooden.
Thanks
Rob

May 21, 2018 | 01:15 PM

Cutlassmaster

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From: Fredericksburg Virginia

What kind of vacuum are you pulling at bnb idle? Mine is about 10 in park and 9ish in gear. My brake feels fine.

May 21, 2018 | 01:27 PM

billschroeder5842

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From: Southlake, TX

Quote:

Originally Posted by Rob 93ZR-1

Did or does the big cam make the brake pedal feel different?

That is the way to bet. Any time you change the vacuum for vacuum operated mechanism, the mechanism will react differently.

May 21, 2018 | 01:28 PM

Rob 93ZR-1

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From: Fear causes hesitaiton...and hesitation will cause your worst fears to come true. Houston TX

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Quote:

Originally Posted by Cutlassmaster

What kind of vacuum are you pulling at bnb idle? Mine is about 10 in park and 9ish in gear. My brake feels fine.

Have not put a gage on it. I was thinking about the ol' put my finger in the hole method to see if it sucks. I just don't know why my pedal feels off intermittently.

Thanks

May 21, 2018 | 01:46 PM

billschroeder5842

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From: Southlake, TX

Quote:

Originally Posted by Rob 93ZR-1

I just don't know why my pedal feels off intermittently.

If I recall, there is no check valve holding vacuum to the diaphragm. Your vacuum (and pull) will vary with the RPM of the engine so depending on when you brake your pedal will feel different.