351W Timing
Thread Starter
|
MSEE
Joined: Apr 2004
Posts: 10,386
Likes: 35
From: Austin, TX
351W Timing
I've got a '77 351W in an LTD. It runs fairly smooth and gets a decent 15 mpg, but it has no power whatsoever. My 400 with a dead cylinder and 150,000 miles has a lot more pep than this thing. I suspect timing has something to do with it. The valve cover sticker calls for 4 degrees BTDC, with vacuum advance disconnected. That's how I have it set up. But the vacuum advance is hooked up to manifold vacuum, so the timing starts out pretty high and drops as you give it gas.
I thought it would make sense to bump the timing up a little more, and route the vacuum advance to ported vacuum. I am getting a little spark knock when I'm going up a hill at highway speeds, if I full-throttle it. What do you all think?
I thought it would make sense to bump the timing up a little more, and route the vacuum advance to ported vacuum. I am getting a little spark knock when I'm going up a hill at highway speeds, if I full-throttle it. What do you all think?
Moderator
Joined: Jan 2001
Posts: 56,997
Likes: 2,744
From: Virginia
Disconnect the vacuum advance, and then rev the engine up. See if the timing advances. If it doesn't, then your advance weights in the dist are stuck.
Most Fords I have messed with run ported vacuum on the dist. There will not be any difference while driving, but having manifold vacuum on the dist makes the idle a little bit high, and makes an automatic bang into gear.
Most Fords I have messed with run ported vacuum on the dist. There will not be any difference while driving, but having manifold vacuum on the dist makes the idle a little bit high, and makes an automatic bang into gear.
Elder User
Joined: Feb 2003
Posts: 850
Likes: 0
From: Winnipeg Canada
Originally Posted by Franklin2
Disconnect the vacuum advance, and then rev the engine up. See if the timing advances. If it doesn't, then your advance weights in the dist are stuck.
Most Fords I have messed with run ported vacuum on the dist. There will not be any difference while driving, but having manifold vacuum on the dist makes the idle a little bit high, and makes an automatic bang into gear.
Most Fords I have messed with run ported vacuum on the dist. There will not be any difference while driving, but having manifold vacuum on the dist makes the idle a little bit high, and makes an automatic bang into gear.
Thread Starter
|
MSEE
Joined: Apr 2004
Posts: 10,386
Likes: 35
From: Austin, TX
Yeah, it's running very sluggish and just has no power. I'm getting some pretty noticeable pinging at mid throttle. I know my EGR is out, too. I'm going to go get an adjustable vacuum advance, hook it up to ported vacuum, and bring up the initial timing. What should I bring the initial timing to?
Thread
Thread Starter
Forum
Replies
Last Post
1975FordF250
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
19
Jul 4, 2014 01:51 PM
alchemist1
1973 - 1979 F-100 & Larger F-Series Trucks
14
Jun 27, 2013 04:08 AM
KenRebF-250
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
4
Jan 30, 2013 11:20 AM
Superred2
Ford Inline Six, 200, 250, 4.9L / 300
5
Dec 15, 2010 11:43 AM
pootscratch89
Small Block V8 (221, 260, 289, 5.0/302, 5.8/351W)
3
Jan 21, 2007 09:12 AM
