Replacement exhaust manifold question
Thread Starter
|
New User
Joined: Sep 2014
Posts: 12
Likes: 0
Replacement exhaust manifold question
Hi guys first post here, but I purchased my first pickup about a month ago for $600. 1985 f150 with a 351W. All in all pretty good condition but needs some work, I wanted a project. I found a suitable replacement exhaust manifold for the current one that is cracked, and loud as can be, but it's a little rusted and dirty. The rust I can take care of, but I'm wondering if I should snake the inside of it or if I should just leave it alone and drop it in..
I have pictures if needed but only have my phone for internet so uploading is a pain
I have pictures if needed but only have my phone for internet so uploading is a pain
Posting Guru
Joined: Apr 2011
Posts: 1,636
Likes: 5
From: Orlando area
I suppose it depends on where you got the manifold from. If it was laying around on the ground at the salvage yard, I would look inside for nests and such, but the entire manifold is only like 14" long so it shouldn't be too hard to check for obstructions.
You should also check the flanges for warping. Lay a straight edge across the mating surfaces. If it is excessively warped you may need to take to machine shop for resurfacing else you could have a hard time getting a good seal.
You should also check the flanges for warping. Lay a straight edge across the mating surfaces. If it is excessively warped you may need to take to machine shop for resurfacing else you could have a hard time getting a good seal.
Thread Starter
|
New User
Joined: Sep 2014
Posts: 12
Likes: 0
It was all connected, I didn't see anything but some light carbon build up inside, but will go ahead and scrub it out. I also noticed my current exhaust has a pin that rotates around when the engine is running, it sits right where the manifold connects to the pipe, but I have yet to see one on another engine.. Any ideas on what it might be?
FTE Legend
Joined: Jul 2010
Posts: 32,875
Likes: 48
From: Northeast, OK
If yours is the HO with a Holley carb then I think what you are seeing may be the heat riser. It is an add-on piece at the exit of the driver's side manifold. Only the HO's had that from what I've seen, and I believe the HO manifold is about 1 1/2" shorter to account for that. So the new manifold should fit as its length is about what the HO manifold plus heat riser's length is. But you should check that first as the exhaust pipe isn't likely to accommodate much difference in length.
Trending Topics
Thread Starter
|
New User
Joined: Sep 2014
Posts: 12
Likes: 0
I'd love to get a set of headers, but I'm working on a down payment for a house right now, so it's gonna have to wait unfortunately.
Not sure what HO is but it has an edelbrock carb on it.
Not sure what HO is but it has an edelbrock carb on it.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
FTE Legend
Joined: Jul 2010
Posts: 32,875
Likes: 48
From: Northeast, OK
Yes, the 351HO as it was called was a souped-up 351W with a different cam, a 4bbl cast iron intake, and a Holley-made carb. As said, the exhaust had a heat riser valve on the outlet and there was a little valve in the heat passage of the intake manifold as well, with both being controlled by vacuum.
Thread
Thread Starter
Forum
Replies
Last Post
browntown3
1999 - 2016 Super Duty
26
Nov 9, 2010 07:21 PM
dillon
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
1
Sep 25, 2000 02:02 AM