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170cid spark plug gap?

Geiri

Newbie
Joined
Aug 22, 2007
Messages
119
Loc.
Iceland
I recently changed my spark plugs and wires, and my 66 is running worse afterwards

What is the recommended gap?
See screenshot of what I bought.



1.jpg









ATH.jpg
 

B RON CO

Contributor
Bronco Guru
Joined
Jun 29, 2016
Messages
2,412
Loc.
Statesville, NC
Hi, if you have the original points and condenser ignition the gap should be
.035.
Double check the firing order.
Did you do anything else besides spark plugs?
Good luck
 

1970 Palmer

Full Member
Joined
Mar 2, 2020
Messages
455
What plug gap did you set on the new plugs before you installed them?

Original factory gap was .035". Modern high energy ignitions can run better with a wider gap.

What kind of ignition system? Do you still have points? If points. what dwell/gap are they adjusted? Initial timing set to? Is the vacuum advance still working? Do you have the correct carb to operate the load-o-matic ignition?

What exactly does "running worse" mean? We would need more information than given to help you diagnose.
 
OP
OP
Geiri

Geiri

Newbie
Joined
Aug 22, 2007
Messages
119
Loc.
Iceland
Hi, if you have the original points and condenser ignition the gap should be
.035.
Double check the firing order.
Did you do anything else besides spark plugs?
Good luck
What plug gap did you set on the new plugs before you installed them?

Original factory gap was .035". Modern high energy ignitions can run better with a wider gap.

What kind of ignition system? Do you still have points? If points. what dwell/gap are they adjusted? Initial timing set to? Is the vacuum advance still working? Do you have the correct carb to operate the load-o-matic ignition?

What exactly does "running worse" mean? We would need more information than given to help you diagnose.
@B RON CO No other changes made

@1970 Palmer I just installed no changes. Engine is stock. Everything ran okay before. But the wires did not look good.
I sounds as she hesitates or misses. My first thought was the gap.



I will pull the plugs and set all to ,035
Hopefully that will solve the issue

Thank you
 
Last edited:
OP
OP
Geiri

Geiri

Newbie
Joined
Aug 22, 2007
Messages
119
Loc.
Iceland
Upgrade: I found a spark plug with smaller gap and corrected it. All is good now :)
Thank you for the help
 

bmbm

Sr. Member
Joined
Jun 16, 2007
Messages
575
Nice 66 Bronco Geiri. An ignition upgrade is something to contemplate. Check out fordsix.com for info on this and much more.
 

1970 Palmer

Full Member
Joined
Mar 2, 2020
Messages
455
Just a FYI. New plugs might be correctly gapped at the factory. But they still need to be checked for the correct gap "Before Installation" because if they are dropped in the box and land on the ground electrode they can close up, even to having "No Gap". So.........Best Practice is to always check them before they are installed. It only takes thirty seconds and look at how much beer drinking time was lost.

Converting over to a more modern mechanical and vacuum advance distributor is a sound performance improvement. fordsix.com is a good resource for this information.
 
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