SilverR1

I see a lot of people running singles use cold plugs. I'm currently running all 9's and want to run more boost. Say 20 or more. I want to use some colder plugs but the normal ngk ones are so expensive. I see people using an alternative ngk plug in the 10 or colder. Are these a lot cheaper and were can I buy them online.

I'm also running the HKS twinpower and was wondering if this is adequate with the stock coils? Is the MSD and their coils a better setup? I was thinking about running 3 msd ignitions and maybe 3 or 4 msd coils. Let me know if it is worth me upgrading the HKS if I run higher boost.

Thanks for any feedback.

Silver93T

Someone found a snowmobile plug or something that works well and is pretty inexpensive. I think it was rice racing.

RX794

Rule of thumb when picking out plugs is basically to use the hottest plug that you can run safely without detonation so that you get a good spark.

RICE RACING

Not in a turbo car !

Rule is run the coldest plug you can, if you have a misfire you need a stronger ignition system !

You can cheat and run hotter plugs with race fuel and low use like drags, but for extended operation on normal fuel you need cooler plugs for reliable operation.

Silver93T

Hey Peter are you the guy that was using the snow mobile plugs?

Alpine

Riceracing said to use NGK B10EGV

Racing beat said you can also use B*EV or B*EVX. * is for any number, like 9 or 10 or 11.

I found these plugs at local motorcycle dealer for $4-6 a piece.

You need to use the thinwall spark plug socket, which is available at racingbeat for $70. It's a thin wall socket, otherwise you won't be able to install your plug, because of the lip around the spark plug hole. These look like normal piston spark plugs, and they are short body plugs. Riceraicng suggest to gap it to 0.02 inches.

I tried B9EGV all around a while ago on my fd, the throttle response did seem to be better, and the car seem to be pulling alittle harder than NGK 9s. However after 2 month of use, my car developed a very lumpy idle. I took out the B9EGV and one of them has a burned electrode that connected all the way to the hook thing.

Randy

mako

iTrader: (5)

I also run the NGK B10EGV found at your local motorcycle shop.


another user on the forum is selling a cut down thin wall socket. for $20 shipped. there is a post under the forsale section. i Just got mine in the mail today.

I was told the plugs are only good for around 5000 miles. still a lot cheaper than the $30 ngk racings.


James
93 mb

faster7

I'm trying out NGK R5671A-9 (also available in heat range 10, 11) These are VERY inexpensive and since they're 5/8 hex, no special socket needed. Work great for me.

At least one friend that's making much more power than I has ran the B9EGV in the past. Will have his opinion of the R5671A's soon.

I'm going to stick by his (and others) advice to gap the plugs tight, like .022-.024 unless running healthy aftermarket ignition.

If I could have picked, or had enough more mods it was necessary, I'd start with the heat range 11 and see how long it takes to foul. If it's livable, I'd stick with it, otherwise step down one. (They had the -9's in the warehouse in town, -10 or colder would have been a few weeks and my car is pretty mild)

R

RX794

The person who started the thread was asking about 20+psi, so I was assuming he was using race gas.

fdracer

not necessarily, people run over 20psi in socal all the time just puttering around on the streets. imo, i don't think a twin power can run plugs any colder than 9s for street driving. start up will be difficult especially on cold days, you'll likely flood the engine cause the ignition isn't strong enough to ignite that cold a plug. when the engine is not fully warmed up idle and drivability will suck. imo, it's better to lean out the motor a tad, that'll give you the same power as a colder plug, and not only is the upgrade free, you'll actually save money on gas.

faster7

I can't recall any mention of a colder plug being harder to fire. Can you show me where theres some documentation?

Colder plugs have the insulator and other parts of construction built such that lots of combustion heat will travel THROUGH the plug to the main plug body, and then to the engine. Hotter plugs let the electrode and to an extent ground strap get warmer.

More boost/power and certain other tuning related items put more heat into the combustion process. Hence colder plugs for "hotter" applications.

Warm enough to cook off some deposits but not so warm that the hot ground strap/electrode ignites the mixture on it's own. Isn't that the whole goal?

(Yes, if the too-cold plug gets fouled, it's THEN harder to fire...)

JScott

Faster 7 nailed it on the heat range issue.

I've been using the B9EGV's with great success. I had bad misfires with the BUR plugs up high. Their gap is too wide and non adjustable for higher boost. And yes, I've been to the dyno w/ a wideband, I am tuned to 11.2-11.6 across.

I'm getting ready to try the R5671A next. Maybe start with a 10 and see if it fouls. These would be a lot easier to change with the 5/8 hex.

fdracer

hmmm, interesting theory, but i've always thought that the reason they do foul is cause they don't ignite well when the engine is cold. i've tried colder plugs w/ the stock ignition and it didn't start as easily, nor did it run as well before being fully warmed up. i've always thought it's cause my ignition wasn't strong enough to get a good burn w/ the colder plug when the engine wasn't fully warmed up.

rotorbrain

the plug will spark but the mixture is harder to ignite as the heat range gets cooler.

paul

fdracer

why would the mixture be harder to ignite w/ a colder plug if the spark is the same. the ignition must therefore not be sufficient to light up a colder plug.