14 replies to this topic

[Surestick]

I side-gapped a set of plugs as per the article in the recent issue of GRM & installed them yesterday.
First impressions are the engine seems to run a bit smoother & start/idle easier (I don't have to keep the choke on as long and idle seems to drop less when I turn on the lights/rear defroster).
No discernable difference at higher RPM but then my butt-dyno isn't that sensitive.
I guess I'll see if it makes any difference in gas mileage.
Drove around feeling all racerish afterwards

Well see how long they last I guess...

Easy mod with a Dremel though.
If I were to do it again I would stuff the cavity between the insulator & the threads with bits ot paper towels or something so I didn't have to worry so much about getting all the little bits of metal from grinding the electrode strap away out of there.

[nivek2002]

Care to explain this to those of us who havent renewed their subsribtion?

Kevin

[speedfreak198420]

side gapping

Look at the pics at the bottom. Looks like in theory it might work. Dont know if it would be worth it though.

Might be interesting to try with some cheap plugs.

Jeff

[hoopty dx]

Ive got to try this

[Surestick]

It does seem to work.
The car feels more eager at lower RPMs & I think I probably have to use less throttle for a given speed (I keep giving it too much gas).
Plugs don't last as long though.
Thanks for the link speedfreak

[G1tegZc]

doing this will cause a hotspot for sure..........

I wouldn't recomend this.........

it sets the spark to a certain side and not directlly down the middle..

Maybe for only racing.......

But daily driving could cause problems

[hoopty dx]

doing this will cause a hotspot for sure..........

I wouldn't recomend this.........

it sets the spark to a certain side and not directlly down the middle..

Maybe for only racing.......

But daily driving could cause problems

<{POST_SNAPBACK}>

You could just put a mark on the plug where it facing down and when you put it in stop turning when its pointing down

[Ryland]

as the artical says, it's not a new idea, we have some antuqe spark plugs some where that are of a simaler design, I'm pretty sure they are of a brand that is stilla round A/C delco or Chamipion, so the fact that a popular plug commpy like that stop making that style really makes me wonder about lifespan, of course you can get the side electrode platnum plugs... but they have other big design differnce past the shorter arm.

[Buford]

I've always used racing side gap plugs (not modified street plugs) on the race cars that i've worked on.....Formula 3 and Formula 2 Cosworths / BMW's. The Cosworths and BMW used 10mm plugs. The F3's had stock heads in which an insert was inserted in the 14mm hole(before head work was done) to accept the 10mm plug.

Anybody tried this on a Honda?

[G1tegZc]

cool post.........but in general........
Bad idea to be leaving that in your car for while.........
If it was such a great design....they would have marketed it.......Platinum plugs don't go bad nearley as easy and they still don't sell them for dailly driving............

probally good for the strip though!

[speedfreak198420]

No prob on the link, Surestick.

Kinda peaked my curiosity, so i had to find out.

L8R

Jeff

[Surestick]

If it was such a great design....they would have marketed it

I think the reason they don't market it (for daily driving) is because they don't last as long.
1-Most people don't want to replace they're plugs often, I don't mind.
2-When plugs start to go bad emmission go up so they might not be "CARB" approved.
There is a company that makes them & markets them as "Race plugs", it's mentioned in the article in GRM but the mags at work... Could be A/C Delco, not sure.

doing this will cause a hotspot for sure..........

I wouldn't recomend this.........

it sets the spark to a certain side and not directlly down the middle..

Maybe for only racing.......

But daily driving could cause problems

I'm not sure why it would cause a hot spot, the only part you are modifying is the ground strap (is that the right name?) and you are making it shorter which should keep it cooler. You aren't making it pointy or anything that would cause a hot spot so...

Can you explain how it would cause a hot spot?

The spark is not down the middle, and??? The whole idea is to unshroud the area where the spark occurs so the flame kernel can propagate faster & with less in it's way. Anyway, the spark that occurs accross the plug gap is not going to be in the same place all the time, it will take the path of least resistance which will depend on the make up of the air around the plug. Ever wonder why the electrode wears away at the side & makes it rounded as a plug gets old? The sides are where the spark happens most of the time because of the shape of the electrodes (sharp edges cause a concentration of charge - the reason why lightening rods are pointed). Side gapping causes it to happen on one side only (hence the accelerated wear).

Daily driving is not going to cause probs unless you don't replace the plugs when they start to wear. If it happens after a few hundred km I'll give up on this. If they last a year I'm fine with that.

I don't mean to jump down your throat but if you are going give opinions please back them up. I don't mind arguing theory but just throwing out opinions without backing them up doesn't help anyone to decide if this mod is for them or not.

[pmpicci]

They don't sell plugs with rounded outter electrodes because it isn't cost effective. Think about how much effort would have to go into setting the outter electrode into a rounded shape, and for what? A few fractions of a hp. I'm not sure what makes anyone think platinum plugs aren't for daily driving or that they don't last very long since the only real significant benefit of platinum plugs is that they last longer. I run platinums in my 82 Cressida, and I keep them in for about 30k mi or so and they could have easily given me another 10k. Never had a problem yet. As far as hot spots, you would theoretically reduce one hot spot area by rounding off the edges. Edges are a main cause of hot spots. The whole point of the exercise is to make up for the engineers' overdesign. Each recommendation made in the article is given for those that autocross in stock classes and daily drive their vehicles.

[badpenny]

so basically they are shortening the arm to increase the flare area? In theory this would also help fuel burn more clean and thourowly(spelling)

and with that said it could also be why they aren't made anymore. Ever heard of emmissions? EGR valve perhaps? I don't mean to crap on anyones parade but, The standards change, so do the engines so do the performance ratios. It could possibly be the fact that a simple solution was to simple. (Blame capitalism)

[Surestick]

In case anyone is interested:
After 6 months with these plugs installed here is what I noticed:
1- They worked well at first (the engine felt a bit more responsive and started a bit easier) but they wore out fast. After a couple of months my fuel efficiency started to fall & the engine felt like it was softer (for lack of a better way to describe it).
2- I pulled them yesterday and the gap was BIG. I didn't measure it but I would say maybe 1½ times the gap they were set at when I installed them (0.041"). I guess what they say about them wearing faster is true!

So - final analysis: They work but unless you change your plugs every month they aren't worth it.

They've been replaced with NGK iridiums.