spark plug gap

**dav-02ws6-m6** · 03-24-2010, 10:13 AM

hey guys i was hoping if somebody can help me.. the thing is like i said on my other post that i was going to do the tune-up on my car. well i finally started today BUT i was getting ready to start on the spark plugs when realize that i didn't know the the spark plug gap... the car has boush 4 tip spark plug and i am going for NGK iridium IX ( TR51X ) i dont have anything on the car right now except for the air lid. cb and maybe latter some LT headers. thank you an advance for all the help...

**cammed goat** · 03-24-2010, 03:22 PM

If I remember correctly, the gap for the LS1 is .40 or .45. I could be wrong though. Others will chime in here.

**pajeff02** · 03-24-2010, 05:07 PM

My TR55's are gapped at .054". Not sure what to do with a platinum tip plug. Cutlass just posted some great info on plugs -- I'll find it and post the link.

**pajeff02** · 03-24-2010, 05:08 PM

Here it is: http://www.ls1.com/forums/showthread...&highlight=NGK

**Cutlass** · 03-24-2010, 05:59 PM

Anywhere around .050" is pretty reasonable for our cars. There are reasons to go a little bigger gap and there are reasons to go a little smaller gap. Pick a number and go with it

You can look up your plugs on NAPA's website and they'll list the recommended gap
Plus I think the NGK's come pregapped so just check them all and make sure there all the same.

**dav-02ws6-m6** · 03-24-2010, 11:24 PM

thank you guys

**dav-02ws6-m6** · 03-24-2010, 11:39 PM

well i check the NGKs and they are set up on .035 so i'll just go on the 40's thanks for the help again..

**rbob93** · 03-24-2010, 11:50 PM

http://www.acdelcotechconnect.com/pd..._03D-J-171.pdf

That is all.....

**blackbird0230** · 03-25-2010, 12:14 AM

I went with .40 on my NGK55's
Although I think .50-.60 is recommended.

**dav-02ws6-m6** · 03-25-2010, 07:14 AM

yea i'm thinking i'll go from 40 to 45 sense i don't have any mods on the car.

**dav-02ws6-m6** · 03-25-2010, 10:44 AM

well guy i'am done with the spark plug. i already went and drove it an seem like they are working fine. i just hope that i don't have to do that in a while. thank for all the input and help.

**cammed goat** · 03-25-2010, 03:41 PM

Shouldn't have to. Enjoy.

**Lawnboy** · 03-25-2010, 08:57 PM

The stock gap is big! around 55, some say 60, i run TR6IX NGK's , awasome plugs , car runs smoother with them.

OK i run a 32-35 spark gap , Yes its tight , but i am procharged and at 15 psi, with the high cyclinders pressures a small gap keeps the spark strong, and wont blow out.

on a NA car i would stay with a 45-50 gap for a better burn

The bosh 2, 3 or 4 tip plugs are not a good choise in the LSX motors IMOP,

i seen a car that was being dyno tuned and the dyno, the dyno spark plug wire pick up couldnt read the rpm of the motor, it was becuses of the 4 way bosh plugs that the customer was using, I guess it was causing a multi spark and the pick up was reading it wrong