Notices
1987 - 1996 F150 & Larger F-Series Trucks 1987 - 1996 Ford F-150, F-250, F-350 and larger pickups - including the 1997 heavy-duty F250/F350+ trucks

Eddy 3881 clearance

Thread Tools
 
Search this Thread
 
Old Jul 11, 2021 | 12:59 PM
  #1  
mat-it's Avatar
mat-it
Thread Starter
|
Mountain Pass
20 Year Member
Liked
Joined: Jan 2005
Posts: 116
Likes: 31
From: Langley B.C.
Eddy 3881 clearance

Wondering what others have seen for clearance to firewall with the Eddy 3881 manifold on a F250 5.8L. What gap would be needed to eliminate possible contact from engine twist? Just got my motor in and am not happy with this “custom” design piece.
 
Reply
Old Jul 11, 2021 | 01:41 PM
  #2  
R&RFord's Avatar
R&RFord
Fleet Mechanic
10 Year Member
Liked
Loved
Community Favorite
Joined: Aug 2015
Posts: 1,835
Likes: 363
From: Candy Mountain
I had to do some "gentle" grinding on the intake after the engine came out and went back in for the rebuild. It wasn't a problem before, but I suspect the engine may have been sitting ever so slightly **** eyed before... anyway, now it only beats on the firewall when I give it some throttle in reverse. Others have also beat in the firewall a bit.

I think that mine wouldn't be an issue if I replaced all the body mounts... but that is such a PITA.
 
Reply
Old Jul 11, 2021 | 02:31 PM
  #3  
My4Fordtrucks's Avatar
My4Fordtrucks
Hotshot
10 Year Member
Liked
Loved
Community Favorite
Joined: Jun 2015
Posts: 12,830
Likes: 2,436
Originally Posted by R&RFord
now it only beats on the firewall when I give it some throttle in reverse. Others have also beat in the firewall a bit.

I think that mine wouldn't be an issue if I replaced all the body mounts... but that is such a PITA.
Sort of the same on my ‘87 Bronco. It doesn’t so much bang into the firewall in reverse but there is a vibration where it must be rubbing.
 
Reply
Old Jul 12, 2021 | 12:02 AM
  #4  
wwhite's Avatar
wwhite
Logistics Pro
10 Year Member
Community Influencer
Loved
Community Favorite
Joined: Aug 2014
Posts: 3,558
Likes: 852
Originally Posted by mat-it
Wondering what others have seen for clearance to firewall with the Eddy 3881 manifold on a F250 5.8L. What gap would be needed to eliminate possible contact from engine twist? Just got my motor in and am not happy with this “custom” design piece.
What truck and year?
I have 1994 F150 regular cab 2wd short box, with zero clearance issues. I can fit my hand between firewall and 3881.
There's a good 1.25 to 1.5" gap, zero contact issues.

My understanding, is that trucks with old/worn body mounts, old/worn engine mounts. 4x4's etc.....who knows what else might be bent, will have clearance issues.
Having good/new engine and body mounts, you will not have clearance issues.
 
Reply
Old Jul 12, 2021 | 01:35 AM
  #5  
mat-it's Avatar
mat-it
Thread Starter
|
Mountain Pass
20 Year Member
Liked
Joined: Jan 2005
Posts: 116
Likes: 31
From: Langley B.C.
It’s a 97 HD 4x4, new motor mounts. I have less than a 1/4 inch. I will run it but I am not keen on taking a sledge to the firewall or doing any grinding. If it doesn’t work I guess i’ll look into a single TB intake or port the old one. After all the work it’s a bummer.
 
Reply
Old Jul 12, 2021 | 08:09 AM
  #6  
GNR22's Avatar
GNR22
Logistics Pro
10 Year Member
Liked
Loved
Community Favorite
Joined: Mar 2011
Posts: 4,197
Likes: 558
From: Central Wisconsin
On my '89, I had maybe 1/8" of clearance between the intake and the firewall/wiper cowl. I bashed this in a half inch or so just to make sure it would never touch. You can't really even see where I hammered this in since it is behind the intake anyway.

If you think that's rough to hammer this in for the Edelbrock intake, to fit a Trick Flow Box R in one of these trucks, you have to cut open the firewall that goes up to the wiper cowl completely.
 
Reply
Old Jul 12, 2021 | 11:28 AM
  #7  
wwhite's Avatar
wwhite
Logistics Pro
10 Year Member
Community Influencer
Loved
Community Favorite
Joined: Aug 2014
Posts: 3,558
Likes: 852
I would have to assume it is something else that is causing clearance issues, not the 3881.
There are only a handful of posts that have clearance issues, blaming the 3881, then they bash the firewall in with a sledge hammer! I wonder how many of those trucks end up with cracked wind shields?
If you are not the original owner of the truck, you will never know how much or little it has been banged up, or bent up.

I agree they are tight fitting, but if its hitting the firewall in forward or reverse, its going to be bad tranny mount, engine mount, and or cab mounts.

Some with rusty cab mounts might even blame the 3881. There's no way a rusty cab could bend that much? Right?
 
Reply
Old Jul 12, 2021 | 01:39 PM
  #8  
mat-it's Avatar
mat-it
Thread Starter
|
Mountain Pass
20 Year Member
Liked
Joined: Jan 2005
Posts: 116
Likes: 31
From: Langley B.C.
So on the upper compressed rubber of my rear cab mounts i’m measuring about 2 inches, 1+1/4 on middle ones and 3/8 on the front. Don’t know if there toast or not.
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

Rezvani's Latest Post-Apocalytic Monster Is a Ford F-150 Raptor Underneath

 Verdad Gallardo
story-1

Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

 Joe Kucinski
story-2

2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

 Brett Foote
story-3

Top 10 Ford Truck Tragedies

 Joe Kucinski
story-4

AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

 Brett Foote
story-5

Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

 Michael S. Palmer
story-6

Ford's 2001 Explorer Sportsman Concept Looks For a New Home

 Verdad Gallardo
story-7

10 Best Ford Truck Engines We Miss the Most!

 Joe Kucinski
story-8

2026 Shelby F-150 Off-Road: Better Than a Raptor R?

 Brett Foote
story-9

2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

 Michael S. Palmer
Old Jul 12, 2021 | 01:43 PM
  #9  
GNR22's Avatar
GNR22
Logistics Pro
10 Year Member
Liked
Loved
Community Favorite
Joined: Mar 2011
Posts: 4,197
Likes: 558
From: Central Wisconsin
Originally Posted by wwhite
There are only a handful of posts that have clearance issues, blaming the 3881, then they bash the firewall in with a sledge hammer! I wonder how many of those trucks end up with cracked wind shields?
Probably none. The part of the "firewall" that is in the way is part that protrudes forward around the wiper cowl. Totally separate piece from where the windshield mounts, luckily.
 
Reply
Old Jul 12, 2021 | 02:25 PM
  #10  
wwhite's Avatar
wwhite
Logistics Pro
10 Year Member
Community Influencer
Loved
Community Favorite
Joined: Aug 2014
Posts: 3,558
Likes: 852
Originally Posted by mat-it
So on the upper compressed rubber of my rear cab mounts i’m measuring about 2 inches, 1+1/4 on middle ones and 3/8 on the front. Don’t know if there toast or not.
If the front and middle are supposed to be the same height, you've got quite the unintended drop, and would explain clearance issues.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
thenortherner
1999 - 2016 Super Duty
1
Nov 13, 2015 02:10 PM
Notmeofficer
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
6
Jul 14, 2014 11:30 PM
stan'37
Modular V10 (6.8l)
2
Sep 25, 2013 06:54 PM
oldgrayman
1947 and Older Ford Trucks
3
Sep 13, 2012 08:12 AM
dave200
1983 - 2012 Ranger & B-Series
2
Aug 22, 2006 07:51 PM




All times are GMT -5. The time now is 04:25 PM.

story-0
Rezvani's Latest Post-Apocalytic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-05-30 18:33:59


VIEW MORE
story-1
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-2
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE
story-3
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

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


VIEW MORE
story-4
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-5
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-6
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-7
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-8
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-9
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