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 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 02-10-2014, 05:06 PM   #1
ALedbetter1
Registered User
 
Join Date: Dec 2013
Location: Hurley Missouri
Posts: 5
High vacuum readings

My 84 k20 with a 350 is having outrageous vacuum readings. Its pulling about 65 at an idle at the intake. This is a lot more than the typical 17 to 22. What could be the culprit? Its got a edelbrock performer eps intake and a Holley 750 cfm carb too.
ALedbetter1 is offline   Reply With Quote
Old 02-10-2014, 05:21 PM   #2
BMERDOC
Registered User
 
BMERDOC's Avatar
 
Join Date: Jun 2011
Location: Richmond,Va
Posts: 2,934
Re: High vacuum readings

Are you sure you are reading it right? There is no such thing as vacuum over 30 hg. in.
__________________
Nick Carter
1967 C10 Short bed Fleetside
Project Cheap Thrills!
2WD C10 Modern/Performance Alignments
Easiest Alignment Ever!
BMERDOC is offline   Reply With Quote
Old 02-10-2014, 06:57 PM   #3
mrolds88
Registered User
 
Join Date: Jul 2011
Location: WV
Posts: 946
Re: High vacuum readings

Quote:
Originally Posted by ALedbetter1 View Post
Its pulling about 65 at an idle at the intake. This is a lot more than the typical 17 to 22. What could be the culprit?
Culprit, I do believe, may be, just may be the vacuum gauge.
__________________
72 GMC C2500 402/Th400 first truck (still have)
77 GMC C3500 CC dually Sold
70 C50 dump truck "Rusty"
87 K10 Suburban Sold
93 K2500 xcab 6.5TD
96 GMC K2500 Suburban 6.5 TD
mrolds88 is offline   Reply With Quote
Old 02-10-2014, 08:07 PM   #4
ray_mcavoy
Registered User
 
Join Date: Nov 2009
Location: Sherman, ME
Posts: 2,367
Re: High vacuum readings

You're not reading the metric Kilopascals (kPa) scale by mistake are you? 65 kPa = 19.2 inHg.
ray_mcavoy is offline   Reply With Quote
Old 02-10-2014, 09:22 PM   #5
S10Fan
Old Heap Driver
 
Join Date: Mar 2008
Location: Newport News, Va
Posts: 2,642
Re: High vacuum readings

Quote:
Originally Posted by ray_mcavoy View Post
You're not reading the metric Kilopascals (kPa) scale by mistake are you? 65 kPa = 19.2 inHg.
Those dadgum kilopascals are sneaky suns a guns..... LOL
__________________
_____________________________
Bryan

'99 Silverado 1500, 4.3, 5-speed, reg cab, short bed
'50 Chevy 2DR Hard Top, 350/350, M2 Front End, 3:08 gear, cruiser.
'40 F**d Sedan, all Chevy power, Heidt's front end, TCI rear, nice driver.
S10Fan 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 12:55 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com