[JHaleyH374]

So I recently replaced the plugs in my car....I had Accel plugs in it (416s) that were gapped on .050 with a 70/78 jet combo in the carburetor and was slightly rich.......well I put a new set in last week and gapped to .035 per Accel's recommendation. Much to my surprise, I get to the track and have to add 4 jet numbers all the way around just to get the car within 2 tenths of what it normally runs in the heat.....evidently the narrower gap strengthened the spark ALOT and really leaned up the motor...it feels much snappier with the 74/82 combo but I am still 2 tenths off....AND the motor is still on the lean side. Think I should step up to 84's in the back next? BTW, this is a 750 carb.

 

[Scott Smith]

Is this the same carb?

Thats the same spec thats in the 750 on my car with 70/78 jets and a 5.5 power valve and it runs excellent....QFT has quite a bit of emulsion even stock....now granted my carb has a .093 slot restriction which makes a difference but I've never had one complaint...runs great, drives great, plugs are clean, and goes faster than any other combo I have tried in this carb. Everyone has their own theory on tuning!

 

[JHaleyH374]

Yup it is....my theory is I had the plugs gapped too wide and it wasn't burning the fuel correctly. So when I screwed in the new set that was correct it gave off a ton more spark and I had to add fuel

 

[Bammer540]

Throw the fuel to it. I run my plugs at .20 in my 632 and had to add 4 numbers from a gap of .25 and I picked up .15 in the quarter. Jet it up until it slows down. The more fuel you can burn the more power you will make.

 

[JHaleyH374]

Throw the fuel to it. I run my plugs at .20 in my 632 and had to add 4 numbers from a gap of .25 and I picked up .15 in the quarter. Jet it up until it slows down. The more fuel you can burn the more power you will make.

I thought so too....just found it kinda strange that .015 less plug gap made that huge of a difference!