how many degrees do you retard your timing per 50 shot of nitrous?Also how many degrees colder on the spark plugs per 50 shot?

 

I believe most vendors reccomend 2 degrees timing per 50 shot. and most guys run a step colder for up to 150 like a TR6 or BR6.

I run a 100 wet shot on the NA tune thats in my 98 with no timing pulled. Plugs look great and went from 12.4 to 11.2 in the 1/4. Also have sprayed 150 on it with the same tune-up without any problems.

I did add 3-4 gallons of 112.

 

runing NOS without proper tuning can be very dangerous. Its like play a game you know your going to loose but playing it anyway. Any time you add power to the car you should tune, will it run .... Yes but for how long


Adding hi octane fuel is like retarding the timeing, that could be why you had no issues, but 100 shot should have 4 degrees pulled to start and read the plugs from there

 

I agree that one should pull timing when running nitrous. I checked the plugs several times at the track and they looked good. Actually had the timing strap perfectly in the middle of the bend. What I'm not 100% sure of if that was created driving back to the pits or how much that timing mark will move if you don't immediatly turn the car off after a pass.

All of the plug and tip were intact with no signs of damage so it didn't bother me too much.

Last wed night I sprayed 150 the entire 1/8 on a 110/93 mix and it ran fine. Bottle was only 900 so it was probably a little fat anyway.

I'm putting my timing twister on this week and going to try and shut the car off at the track to get a good reading on new plugs.

 

The general rule for pulling timing is retard 2* per 50hp.

For plugs i'd suggest this.

50-200hp i'd suggest a NGK BR7EF [ Stock # 3346 ] gapped around 33-35

 

It's good that you are learning to read plugs no doubt. However timing is only half the battle. You must learn to read fuel, search it on here and you will find some good reads. If you're serious shoot me a pm and I can help.

FYI - when you didn't kill the key at the traps and drove back to the pits you just screwed up your read. Idle timing is totally different than WOT. Also try not to get very much idle from pits to staging, it seems that with a fresh plug it doesn't hurt if you just crank up then rush to stage in like under a minute but if you have several minutes of idle in stage then it throws off the read at the big end.

 

Good Post Carter...

 

guys & girls remember to a run a short probed spark plug when using nitrous