Notices
1973 - 1979 F-100 & Larger F-Series Trucks Discuss the Dentsides Ford Truck
Sponsored by:
Sponsored by: Moser

compression test

Thread Tools
 
Search this Thread
 
Old Jan 18, 2012 | 10:27 PM
  #1  
theerod's Avatar
theerod
Thread Starter
|
New User
Joined: Jan 2012
Posts: 13
Likes: 0
compression test

What is the compression suppose to be for '77 F-250 with
460.
 
Reply
Old Jan 18, 2012 | 10:54 PM
  #2  
Bullitt390's Avatar
Bullitt390
Certified Thread Hijacker
20 Year Member
Photogenic
Liked
Joined: Aug 2001
Posts: 14,441
Likes: 59
Club FTE Silver Member

Anything over 130 psi should be good on those tugboat motors. Small cam and very little lift and anemic compression ratio isn't going to produce much.

150-160 would be great. 120 psi is OK.

Be sure to do a dry and wet test and make sure to crank the engine over a couple revolutions with the carb blocked WOT during the test to get the best number for each cylinder.

Josh
 
Reply
Old Jan 19, 2012 | 12:25 AM
  #3  
Stinky7-11's Avatar
Stinky7-11
Elder User
Joined: Aug 2011
Posts: 685
Likes: 0
From: Cape Coral, Florida
Club FTE Silver Member

Also removing all your sparkplugs first and replace them after you have completed testing all cylinders, your starter will love you.

If you do just be sure to number each plug wire.
 
Reply
Old Jan 19, 2012 | 04:49 AM
  #4  
theerod's Avatar
theerod
Thread Starter
|
New User
Joined: Jan 2012
Posts: 13
Likes: 0
Well I think I may have a problem . But first of all I could pull those wires blind folded and reinstall with no problem. This is how the numbers went. No.1-100 lbs. No.2 110 3-90 4-90 5-90 6-95 7-87 8-92
 
Reply
Old Jan 19, 2012 | 05:07 AM
  #5  
Stinky7-11's Avatar
Stinky7-11
Elder User
Joined: Aug 2011
Posts: 685
Likes: 0
From: Cape Coral, Florida
Club FTE Silver Member

You did crank each cylinder through 4 or 5 compression strokes right? To make sure it maxed out? That was dry,are you going to repeat wet?
 
Reply
Old Jan 19, 2012 | 06:15 AM
  #6  
OldStyle's Avatar
OldStyle
Rusty Roller
Joined: Oct 2011
Posts: 1,423
Likes: 5
From: Santa Cruz Mountains
Club FTE Silver Member

Just to add....

Did you start out with a good fully charged battery?

Hand held or screw-in compression tester?

and as mentioned:

5 complete compression strokes

wet test results?
.
 
Reply
Old Jan 19, 2012 | 06:59 AM
  #7  
theerod's Avatar
theerod
Thread Starter
|
New User
Joined: Jan 2012
Posts: 13
Likes: 0
Battery is ex excellent as a matter o fact I have two wired in parallel. Tester is screwed and when the gauge stopped rising I stopped. As far as the wet test I live in Washington St and I don't have to test, I know its wet. Just kidding. I didn't know about wrt test until I was finished. I will definitely let u know how that went
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
rheal
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
1
Apr 15, 2012 06:03 AM
RANGER589
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
8
Sep 3, 2010 10:02 AM
TheNomad
Big Block V8 - 385 Series (6.1/370, 7.0/429, 7.5/460)
11
Jun 18, 2008 08:35 PM
jrolfe
1973 - 1979 F-100 & Larger F-Series Trucks
2
Aug 13, 2002 09:41 AM




All times are GMT -5. The time now is 02:08 AM.

story-0
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-1
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-2
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-3
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-4
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE
story-5
2026 Shelby F-150 Off-Road: Better Than a Raptor R?

Slideshow: first look at the 810 hp 2026 Shelby F-150 Off-Road!

By Brett Foote | 2026-05-12 12:50:07


VIEW MORE
story-6
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

Slideshow: Everything You Need to Know about the 2027 Super Duty Carhartt Package!

By Michael S. Palmer | 2026-05-07 17:51:06


VIEW MORE
story-7
10 Most Surprising 2026 Ford Truck Features!

Slideshow: 10 most surprising Ford truck options/features in 2026.

By Joe Kucinski | 2026-05-05 11:17:22


VIEW MORE
story-8
Top 10 Ford Trucks Coming to Mecum Indy 2026

Slideshow: Here are the top 10 Fords coming to Mecum Indy 2026.

By Brett Foote | 2026-05-04 13:49:49


VIEW MORE
story-9
5 Best / 5 Worst Ford Truck Wheels of All Time

Slideshow: The 5 best and 5 worst Ford truck wheels of all time

By Joe Kucinski | 2026-04-29 16:49:01


VIEW MORE