• Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-

Resolved Need help!! 289 with 351 firing order issues

  • Thread starter Thread starter Falcon67
  • Start date Start date Jun 13, 2024
  • Tags Tags
    289 backfiring idle problem

Falcon67

New Member
Jun 13, 2024
7
0
1
Spain
Jun 13, 2024
#1
  • Jun 13, 2024
  • #1
Hi folks, I have a 1967 289 engine restored 8 years ago with a E-Street top end kit from Edelbrock and DUI distributor. I´ve been unable to finish with this car till this year. When we started it we realized that the only firing order that "works" is the one from a 351 and its imposible to set a normal idle. It backfires thru the carb all the time. My suspicion is that maybe the guy from Summit sent a wrong camshaft to the guys who reassembled the engine is 8 years ago. I´ve heard that a 289 can walk with a 351 cam but Im not sure. I also installed a pressure regulator before the carb thinking that the backfire was caused by overpressure. What do you guys think?
Now one of my big doubts is if the 351 distributor gear teeth the same as the 289? Here you can hear it.

Thanks!!
 

Attachments

  • 846C3FCA-3675-4B11-8F5A-12CA16385498.webp
    454.1 KB · Views: 716

Realmongo

I prefer to be called "Evil Genius"
Founding Member
Oct 10, 2001
2,468
86
99
Western Mass
Jun 16, 2024
#2
  • Jun 16, 2024
  • #2
A 351W cam will work fine in a 289 if the 351W firing order is used.
The distributor gear must be compatible with the cam, or in other words, a cast iron cam needs a cast iron distributor gear, and a steel camshaft needs a steel distributor gear.
 

Falcon67

New Member
Jun 13, 2024
7
0
1
Spain
Jun 16, 2024
#3
  • Jun 16, 2024
  • #3
Realmongo said:
A 351W cam will work fine in a 289 if the 351W firing order is used.
The distributor gear must be compatible with the cam, or in other words, a cast iron cam needs a cast iron distributor gear, and a steel camshaft needs a steel distributor gear.
Click to expand...
Thanks! The distribuitor is a Davis Unified and the cam is the one that came with the Edelbrock kit. Are they compatible?
 

Realmongo

I prefer to be called "Evil Genius"
Founding Member
Oct 10, 2001
2,468
86
99
Western Mass
Jun 19, 2024
#4
  • Jun 19, 2024
  • #4
Falcon67 said:
Thanks! The distribuitor is a Davis Unified and the cam is the one that came with the Edelbrock kit. Are they compatible?
Click to expand...
You will need to refer to the manufacturer's webpage for the exact model of the distributor and camshaft to see what material they are made from. When I shifted from the stock Ford cast iron camshaft to an ISKY steel roller camshaft, I had to upgrade my distributor to a 1985 5.0 distributor that had a steel gear to be compatible with the steel roller cam Ford built that year's 5.0 with.
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,845
3,975
183
Claremore, OK
Jun 27, 2024
#5
  • Jun 27, 2024
  • #5
If the carb has set for a long time it may need to have a kit put in it.
 
Reactions: Falcon67

Falcon67

New Member
Jun 13, 2024
7
0
1
Spain
Jun 28, 2024
#6
  • Jun 28, 2024
  • #6
AeroCoupe said:
If the carb has set for a long time it may need to have a kit put in it.
Click to expand...
we opened it and everything was new.. carb is new but has been siting in the engine for 8 years
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,845
3,975
183
Claremore, OK
Jun 28, 2024
#7
  • Jun 28, 2024
  • #7
I’d put a kit in it sitting that long.
 

2Blue2

will be trying this sex one when I can find it
Mod Dude
Mar 5, 2019
4,430
2,893
163
Oahu
Jul 6, 2024
#8
  • Jul 6, 2024
  • #8
After all the sitting look for things like;
vacuum leak (new gaskets that sat sat and never ran have shrunk)
Carb has an internal leak needs a kit
distributor advance frozen from sitting
coil or module has gone bad
crappy gas

My buddies DUI worked great once the gear was sorted out.
I have a 289 with the 5.0 firing order and it has worked great.
 
You must log in or register to reply here.

Similar threads

T
Engine Need help figuring out misfire and backfire
  • trystancounts
  • Sep 25, 2025
  • Fox 5.0 Mustang Tech
Replies
8
Views
282
Fox 5.0 Mustang Tech Sep 26, 2025
Noobz347
A
95 Gt intermittent backfire
  • A_A_Ron
  • May 26, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
0
Views
415
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- May 26, 2025
A_A_Ron
A
SURGING IDLE / NO IDLE CHECKLIST FOR 1999–2004 MUSTANG GT (4.6L 2V) - Work In Progress
  • Noobz347
  • Aug 30, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
0
Views
872
1996 - 2004 SN95 Mustang -General/Talk- Aug 30, 2025
Noobz347
Place to Avoid: Jamison Auto Group in Gulfport, MS
  • D Durden
  • Oct 20, 2025
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • 2 3
Replies
45
Views
2K
1965 - 1973 Classic Mustangs -General/Talk- Feb 4, 2026
nickyb
So confirming what I need to do to put a '88 CV 302/AOD in my '65 A-code.
  • 1320stang
  • Apr 19, 2023
  • 1965 - 1973 Classic Mustangs -General/Talk-
Replies
7
Views
2K
1965 - 1973 Classic Mustangs -General/Talk- Jun 20, 2023
1320stang
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?