Anyone try these Autolite X Racing Plugs shown below? I've heard some good results. I'd like to think they'd last longer than 70-100 runs with a grid.

Not that the below has much to do with a race engine, I found the spark jump and flame propagation for the Autolite X interesting.

They ain’t no damn better an it feels like your about to strip your heads trying to get the in....I quit using them for this reason

Here are a few questions that you might be able to provide some additional information.

The Autolite X spark plug has a fairly long non threaded ring that extends out into the combustion chamber. That, coupled with the 360 degree firing design extends the plug tip deeper into the combustion chamber. That might become a piston clearance issue in some high compression applications. Comparing the depth of the Autolite X plug, side by side to that of a side mounted projected tip spark plug might give you have a better comparison in determining piston clearance.

The real problem is that there is no advantage to indexing the Autolite X plug to gain piston clearance, you can't re-position the ground strap, it's a 360 degree ground strap.

The E3 racing spark plug ground straps (all three) look as if they extend even deeper into the combustion chamber. When installing them in high compression engine you would have to clock the engine so that no piston was at TDC.

The Pulsar spark plug is the most interesting of the three. It doesn't seem to have the piston clearance issue when properly indexed. The question is how well does it perform in a high compression, high RPM application. Another question is how many heat ranges are available.

Not trying to play Devils Advocate, I am really interested in finding out more about these spark plugs.

Bob

Have a set for the TS car. Just swapped to 3910. We've got other issues to sort out so not time to test the x plugs. I know plenty of fast superstock/stock who run them.

my opinion is they are a gimmick just like split fire and now E3.

Ngk did the worst in the lawn mower. Generator. And go cart in the video. Just kidding. As I stated in another thread I am trying the e3 plugs and do notice some improvements. Did notice they were more air sensitive but gonna try them again this week. Last time I run the air was really really sh1tty and went to just sh1tty so the air may have been out of my jet ideal and come closer to my jet if that makes sense. I like aspects of the e3 but will go back to ngk if my car continues to move more than I like.

ep- I was digging the side exit exhaust on the rv

Autolite X

Is the same design plug they run NHRA Pro Stock.

quote:

Originally posted by pauley:
Ngk did the worst in the lawn mower. Generator. And go cart in the video. Just kidding. As I stated in another thread I am trying the e3 plugs and do notice some improvements. Did notice they were more air sensitive but gonna try them again this week. Last time I run the air was really really sh1tty and went to just sh1tty so the air may have been out of my jet ideal and come closer to my jet if that makes sense. I like aspects of the e3 but will go back to ngk if my car continues to move more than I like.

ep- I was digging the side exit exhaust on the rv

You’ll go back to NGK...

There's nothing magic about spark plugs just as there's nothing magic about shocks.

I run ngk while tuning because they are easier to read and I can get them cheap. Once my tune is happy I switch to autolite racing plugs. Not much difference other than cutback ground strap but they do last longer than the ngk.

quote:

Originally posted by 1320racer:
my opinion is they are a gimmick just like split fire and now E3.

you left out the j.c.whitney "fire injectors"! I agree, they're all gimmicks with different packaging.

yep, same gimmick repackage every decade for the last 40+ years.

They are not a gimmick, but its about 15 year old Nascar race day plug stuff. They are usually with in 5 horsepower on the dyno compared to non X plug.

Gimmick or not, I wouldn't put an autolite in anything but a trash can. I had a miss a few years ago that would come and go. I changed everything I could including multiple sets of plugs. A friend recommended that I try equivalent NGK plugs and it hasn't had the issue since. I can understand a bad plug every so often but to have multiples in multiple sets is unforgivable in my eyes.

I check every spark plug with an ohm meter before it's installed in the race car engine. Years ago I bought a set of AC Delco plugs for my 350 ci '56 Chevy PU. One of the plugs didn't have any threads.

Bob

This message has been edited. Last edited by: RPROGAS, July 24, 2020 11:10 PM

quote:

Originally posted by Duane1791:
They are not a gimmick, but its about 15 year old Nascar race day plug stuff. They are usually with in 5 horsepower on the dyno compared to non X plug.

SHHHHHH Duane! Nascar is light years ahead of development. Cool stuff!
Its something that most don't give a second thought about.

quote:

Alaskaracer

how far u cut strap back

The autolite race plug strap is cut back out of the box. Careful gapping...

Ernie Griggs runs those in his Camaro. Our engine builder likes them.