I just got some NGK Iridium IX heat range 7 for my soon to be turbo'd car. What do you guys recommend gapping them at?
Thanks

 

i wouldn't suggest gapping them....IIRC you aren't supposed to mess with any gapping for plugs on our cars.

 

^He's 1000% right on that! Imports are a little different than traditional domestic. I've been down both roads and flirted with bikes too. Anyways your plugs are ready to install out of the box.

 

How much boost are you running?
12 lbs or more i would run the gap 22-25

 

After some research there is some truth to this... Try asking JeffTsai, bc he has a sick set-up already.

 

im only running 8psi at the moment...so they will be fine for 8 psi?

 

any ideas?

 

run the gap down to 25 it will give you a better spark on the higher end.

 

What is the OEM spec for the gap?

 

Start at .028 and if you are having misfires up top then go down a little bit. When you gap them be careful at the tip is very easy to break. I generally just lightly tap on the plug and check the gap frequently till I get it right where I want it. Use something not too heavy like a small ratchet or something. It sounds funny but that is the easiest way I have found, just be gentle but firm.

 

I run my plugs at .022, but then again I run at around 30psi all the time. Your setup is pretty mild, so there's no need to close the gap down much or at all. Most of the time the way the plug comes pre-gapped is just fine.

 

One thing - if you're using the pregapped setup, make sure you verify they are all set the same. I've had it happen more than once when working on a car that one plug is just a bit off, and it causes funky problems. It's an easy thing to make sure they're done that way.

We had one set of 6 where the gap varied from 0.021 to 0.028. Car ran like total dog caca until we checked the plugs. Got them all gapped to 0.024, and it ran smooth as silk.

Big Mack

 

Im pretty sure all iridium comes pre-gapped but just to make sure to check too see if their all the same....

 

You should gap them down as I mentioned before, here's why:

1. The Gs obviously wasn't designed to be turbo, you are running higher compression than a standard turbo motor. Higher compression plus 8psi plus weak coils = weak spark.

2. The Gs has only 3 coils where a Supra has 6 dedicated coils. Even with 6 dedicated coils the Supra guys run .028 and lower due to high rpm missing, highway pulls are a good example of when those issues show up.

3. The plugs may be factory gapped but they aren't gapped for modified cars with increased air and fuel intake.