Thread: gapping 104's?

i tried searching for an answer didnt come up with anything
so my question is should i gap these autolite 104s and what gap should they be

Originally Posted by TDCRacing

.060

B. I. N. G. O and Parker was his name-o. Beat me to it :P Sending you a PM either tomorrow or end of the week before my gf's parents wedding.

i gap my 103s at .052, but i run more boost than you. .060 sounds good about right for nothing done to the car.

so when i do drop a pulley size which should be sometime soon once i can sell this extra blower and some other things to get a scanner too should i go .052 with a 3.4 ?

not necessarily. you should be going with as big of a gap as you can without being able to blow out the spark. i dont really change mine that often so i just make sure i wont have any problems by gapping them slightly smaller than normal.

Ok, so while we're on this topic.....

Right now I have a 2004 L67 (Monte Carlo SS) with TOG's, 3.4" pulley, cai, and stock wires and coil packs. I'm running Autolite 104's at 0.055 and they work great. Haven't tried going up to 0.060, but just haven't gotten the chance yet.

That said, next weekend I will be adding a gen 5 blower, N* TB, stage 2 intercooler, modded 1.9 rockers, 42.5's, and most likely start with a 3.25" pulley and work my way down....

So, with the new setup do you guys think that I should start out with the 104's at 0.055?
Or am I most likely gonna have to use a closer gap?
Or am I really just gonna have to figure it out by gapping the plugs and checking for misfires?

-Riggs.

Will to small of a gap cause misfires?

Originally Posted by kissmyss

Will to small of a gap cause misfires?

no, too big of a gap will.

Originally Posted by BiggRiggs

Ok, so while we're on this topic.....

Right now I have a 2004 L67 (Monte Carlo SS) with TOG's, 3.4" pulley, cai, and stock wires and coil packs. I'm running Autolite 104's at 0.055 and they work great. Haven't tried going up to 0.060, but just haven't gotten the chance yet.

That said, next weekend I will be adding a gen 5 blower, N* TB, stage 2 intercooler, modded 1.9 rockers, 42.5's, and most likely start with a 3.25" pulley and work my way down....

So, with the new setup do you guys think that I should start out with the 104's at 0.055?
Or am I most likely gonna have to use a closer gap?
Or am I really just gonna have to figure it out by gapping the plugs and checking for misfires?

-Riggs.

i would start with 103s right away since youre going to be running smaller pullies. itll help out just that much more. i would start out with about a .052" gap and see if it flys. unfortuneately yes, youll have to put them in and then run it and check for misfires.

i gapped my 104's at .55

i would start out with about a .052" gap and see if it flys.

Cool, thanks.....
I was really just looking for a starting point so I can get the tune done.
Then maybe the next weekend I can play around with the plug gap.

Too damn bad I have like 20 AL104's sitting around here.
Maybe I'll have to see if Autozone will let me trade w/o a Receipt.

-Riggs.

why dont you sidegap them?

Originally Posted by 2000GTP

why dont you sidegap them?

does it really make a difference? has anyone documented that it has made a difference at all?

no one here owns a race car. i dont get why side gapping the plugs would make a difference at all. i think indexing the plugs would make more of a difference than side gapping and you dont ever hear about anyone doing that.

whats indexing? i havent personally side gapped mine yet, but i plan on it... heard it helps so why not?