The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 12-23-2010, 03:55 PM   #1
mtdave2
newly minted old timer
 
mtdave2's Avatar
 
Join Date: Dec 1999
Location: Hudson WI
Posts: 3,508
Vacuum reading.

What are you guys getting for a vacuum on your 350 at idle? I was at 13 inches, but after plugging some leaks, I am at 17 now. Fresh 383 motor.
__________________
____________________________________________
72 c20 longhorn 65k org miles and counting!
69 k10 Suburban
mtdave2 is offline   Reply With Quote
Old 12-23-2010, 05:16 PM   #2
Fitz
Account Suspended
 
Join Date: Jan 2007
Location: Tucson
Posts: 2,183
Re: Vacuum reading.

You didn't say what cam you're running but for a ZZ4 383 that's a bit high. For a milder cam 17-18 is about all you will get.
Fitz is offline   Reply With Quote
Old 12-23-2010, 06:12 PM   #3
LONGHAIR
just can't cover up my redneck
 
Join Date: May 2004
Location: Columbus OH
Posts: 11,414
Re: Vacuum reading.

It's kind of a "not fair" comparison. Assuming no leaks, the vacuum is mostly dependant upon the cam you choose, and a little on the compression ratio.
__________________
You can review the site's rules here.



Quote:
Originally Posted by Longhorn Man View Post
As for reading directions...
The directions are nothing but another man's opinion.
Learn from the mistakes of others, you won't live long enough to make them all yourself...

Bad planning on your part does not necessarily constitute an instant emergency on my part....

The great thing about being a pessimist is that you are either pleasantly surprised or right.
LONGHAIR is offline   Reply With Quote
Old 12-23-2010, 08:11 PM   #4
mtdave2
newly minted old timer
 
mtdave2's Avatar
 
Join Date: Dec 1999
Location: Hudson WI
Posts: 3,508
Re: Vacuum reading.

http://www.summitracing.com/parts/CCA-CL12-234-2/

Duration 256/268, Lift .447/.454
__________________
____________________________________________
72 c20 longhorn 65k org miles and counting!
69 k10 Suburban
mtdave2 is offline   Reply With Quote
Old 12-23-2010, 08:26 PM   #5
Fitz
Account Suspended
 
Join Date: Jan 2007
Location: Tucson
Posts: 2,183
Re: Vacuum reading.

Quote:
Originally Posted by mtdave2 View Post
http://www.summitracing.com/parts/CCA-CL12-234-2/

Duration 256/268, Lift .447/.454
That's a pretty mild cam so 17-18 is about right.
Fitz is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 09:29 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com