R44TX Spark Plugs say Gap at .60 ??? Sounds like a big gap

[Chief Brody]

When I bought the new spark plugs this time I bought them for the engine year, which is a 1975. They show to be different than the 1974, I guess because of the HEI. Anyway, what comes up is R44TX an it says to gap at .60

I think I am running R44T right now with a .35 gap.

Can anyone confirm the .60 gap for the R44TX ?

 

[Chief Brody]

Sounds like I may have been running the wrong plug because I didn't notice the different plug for HEI. I guess 1974 was a transitional year with HEI option?

 

[diesel4me]

'74 was the first year for HEI I believe..
!975 was a weird year,GM decided to start using super wide gap spark plugs with the "TSX" suffix..some Olds & Buicks had plugs gapped at .080 ..
They soon found out in colder climates that was too wide a gap--many engines flooded after a cold start (usually due to a choke pull off not working or adjusted wrong),and once the engine stalled,you could crank it till the battery died and it would not start,despite having great spark at the plug wires when you checked it--put in 8 new spark plugs and it would fire up instantly..

GM had recall bulletins stating to put the "regular" gap plugs back in gapped at .035-.045 and in '76 they stopped using the wider gap spark plugs..the wide gaps did increase fuel efficiency a bit and make a smoother idle,but they found at high speeds they were more likely to misfire and made for harder cold weather starts..also under high load the spark would want to jump to ground thru the wires or any other spot with lower resistance than firing the plugs..

I have always used R45TS or Autolite 26 plugs in all my small blocks..

 

[dyeager535]

Sounds like I may have been running the wrong plug because I didn't notice the different plug for HEI. I guess 1974 was a transitional year with HEI option?

HEI never really changed, but GM ran different gaps depending on make and engine as has been referenced.

I gap mine at .035, which results in a LONG time before plug wear starts to open the gap up enough that they need re-gapping. I've played around with the gap before for MPG, never could induce enough of a change that I could measure. So for peace of mine, I go .035 and after 10 years or so, re-gap them. lol

 

[Chief Brody]

I actually checked the gap on these and they were not .60, they were .45..all of them

Maybe they gap them at .45 when they make them now?

 

[Justin V]

Run .045. Change them after about 10-15k miles.

 

[fordsucks!]

I run .45, per the sticker under the hood

 

[Dan Myers]

That was the begining years of HEI and if you look at the newer years, say in the early 80s, the gap is .45.

 

[chulisohombre]

I run mine at .038-.040.Never had issues.​