Spark Plug Indexing
 

With indexing the AR3933 spark plugs. If the crush washer does not give it the right position and you install the moroso washer (1 of 3) are you supposed to reinstall the crush washer or leave it off the spark plug since you have a indexing washer on it?

Re: Spark Plug Indexing
 

I've always lrft the washer on the plug, makes sense to seal against the indexing washer. Joe

Re: Spark Plug Indexing
 

what is the widest gap some run on their plugs and what benefit have you seen?

Re: Spark Plug Indexing
 

Randy, wide spark plug gaps went out with ignition points. With todays MSD's and most other manufacters electronics, there is no reason to run more than .025 gap. As a matter of fact, if your trying to run, say .040 - .050, close the gap down to .020 - .025, and you'll see a performance gain. At least that been my experience. ( and don't forget to have your plugs Cryo'd. - go kart trick! )

Re: Spark Plug Indexing
 

on AR3933 plugs leave the gap alone --run em as they come from the factory just check to make sure that the gap did not close up ratteling around in the boxes---Comp 387

Re: Spark Plug Indexing
 

"( and don't forget to have your plugs Cryo'd. - go kart trick! ) " - Jim Bailey

Hey Jim,

Is there a shop you would recommend for doing this?

Bill

Re: Spark Plug Indexing
 

Bill I think their's some guy up in Ohio that dose it when he's not playing with a nitro funnycar! ;)

Re: Spark Plug Indexing
 

Come on now guys... what's the reason or benifit of cryo treating plugs?

Re: Spark Plug Indexing
 

It keeps em cool...

Re: Spark Plug Indexing
 

I don't know about the cyro , but I do sell alot of Autolite AR 3910X and AR3933X to the go cart guys. It's a surface gap plug that has proven to be worth some big gains on their dyno.
Rich

Re: Spark Plug Indexing
 

What is a surface gap plug?

And I just read a post elsewhere and the racer eliminates (not cut back, eliminated) his ground strap. Anybody have any comments on that? I have a hard time fathoming that being effective...

Re: Spark Plug Indexing
 

I am going to try and post some pictures tonight.
Rich

Re: Spark Plug Indexing
 

We dynoed the ground strap off idea,never made any HP but never lost any.I think the no ground strap would be hard on wires and maybe even coils. We like the wider gaps,however after reading Mr. Baileys post I may try tightening up the gaps.

Re: Spark Plug Indexing
 

Here are some pictures of the Autolite X plugs. I have them in AR471X 9, AR3932X, AR3933X, and AR3910X. Any questions call me at 704-784-8376 or Quickford1@yahoo.com
Rich

Re: Spark Plug Indexing
 

Does anyone run these X plugs and have any results, specifically with smallblock alcohol motor?

Re: Spark Plug Indexing
 

Out of curiousity, what is the thinking behind cryogenically treating the plug? I know many Karting guys like surface gap style plugs like the ones shown below. One is a surface gap NGK, the second is a LGS Brisk plug and the last is a multispark Brisk.