Thread: How To: Side Gap Spark Plugs

Anyone???

I'm going to do this in the morning for something to do, was hoping I could maybe get a heads up on what you guys set your gap at, I run a t28 @ anywhere from 9-16lbs depending on my mood at the moment.

Any heads up will be appreciated greatly.

I did this. Bought some new NGK's, gapped them to .34 and got 25 mpg the last tank when I usually get 20. The way I was driving I would guess it would of been a 21 mpg tank..
That's a 4mpg increase that I got

Last time I got 24 mpg when I went on a long highway drive and was driving 65mph the whole way (4 gears) and this was city and highway, about 40% city 60% highway

@red91sr you reduce the gap by .010. But you can try running a bigger gap and it should work fine NA .

@92SentraSE-R - those are some pretty good gains

Yeah I did this back on the 27th of Nov. or something like that, my car has a turdblow BTW. I noticed that after I did it that I had 0 drivability issues with it but that I did start having an issue with a small pop when changing gears, sounded like a tiny backfire issue so I just stuck my old plugs back in. My HIGHLY uneducated guess was that I wasnt achieving complete burn thus causing the small backfire issue???
And no, I dont remember exactly where I gapped them.

thank you for following up on this BTW Vadim!

OP...u r a n o o b

I went ahead and changed the plugs back just to see what kind of mpg's I would get and I got 19mpgs........ lowest I got with the plugs side gapped is 21 driving like crap and lowest with regular plugs driving like crap is 18

update: Drove about 3 tanks with the old plugs and am getting 18-19mpg's so huge difference. 1/30

Update: Put the side gapped plugs in after driving about 50 miles with the regulars and ended up getting 24mpg's with driving pretty crappy.. (also seafoamed the crank)

this is done with only 4 gears, hence the low mpgs

Took the plunge today and decided to side-gap the plugs in my DD P10 VE. Gapped them at .039, but I may decrease it a bit to .034. So far the butt dyno does feel a difference.

I've been doing this for a couple years now, plus indexing them. Mileage is usually has consistently been 2 1/2 to 3 1/2 mpg better. Driving with '91 na car is cai only. I don't even regap the plugs... using bke 6-11's.

Congrats to Vadim for one of the simplest and most useful upgrades, ever.

Mark

Nice! That's a nice bump in MPG's , from a "free" mod



NA I would keep them at .039. Trick is to run the biggest gap possible without blowout.



What led me to this mod is, the Bosch +2 plugs. They don't have a ground electrode that blocks the flame front at the bottom of the plug. Bosch plugs did great on gas mileage, but lasted only 20k miles and cost twice as much as regular coppers. Thus when I found the side gaping trick I was super happy to see my MPG's go up too.

I have another tutorial for indexing. I might just combine them together to save the searching for people .

For reference Bosch +2 plugs
http://www.bosch.com.mx/content/language2/img_productworlds/Platinum_2.jpg