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Spark Plug Gap Question

  • Thread starter Thread starter 1BAD89GT
  • Start date Start date Jan 8, 2004
1

1BAD89GT

New Member
Jan 2, 2004
87
0
0
Oklahoma
Jan 8, 2004
#1
  • Jan 8, 2004
  • #1
Iam wondering if with this engine thats in my sig ,should i change my plug gap...i know stock is .054 but with this motor making 329hp@motor and having 10.7:1 compression,the plugs stay bright white.Im running a 155lph fuel pump and 40psi fuel pressure at idle on 93 octane.

edit:forgot one little detail timing is at 14 degrees
 
1

1BAD89GT

New Member
Jan 2, 2004
87
0
0
Oklahoma
Jan 8, 2004
#2
  • Jan 8, 2004
  • #2
*Bump* I figured this would be a stumper
 

thegabrielles

Member
Feb 26, 2003
516
1
16
Atlanta Georgia
Jan 9, 2004
#3
  • Jan 9, 2004
  • #3
INTERESTING COMBINATION WITH THE B303, should run great, I am runnning .054 in mine as well, but I have considerably less compression than you do. Seems to me, your gap is not going to take care of a lean motor. I am running 45psi on my fuel with 24# injesctors and although I made more power with it leaner 2HP, the Air/Fuel was dropping off to far. With that compression you might want to bump up the pressure a bit. I take it you dynoed thee motor to get 329FWHP, did you run a dyno tune or just a couple of pulls to see what you got? Did they run the A/F on the pulls? I was told by FMS that .054 is wgere I shgould set the gap, hopefully thaey know their own motor.
 
S

sleeper89

New Member
Nov 18, 2002
388
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0
Toronto, Ontario
Jan 9, 2004
#4
  • Jan 9, 2004
  • #4
as long as the plugs look good, she idles smooth, and the a/f ratios are good i would leave the gap as is. it probably wouldn't hurt any to close it up a bit with that much compression though. either way i would say you aren't going to see a big difference.

-steve
 
1

1BAD89GT

New Member
Jan 2, 2004
87
0
0
Oklahoma
Jan 9, 2004
#5
  • Jan 9, 2004
  • #5
Yeah when it was dyno'd it showed Air/fuel mix quality very poor all the way up to 2500rpms which im sure is from the aggressive lopey idle of the b-cam@226, and then the a/f jumps up to 91.4%@3000 and when stomping on it thats when it really seems to come alive you can feel an instant diff when it hits 3grand and above.the A/f Mixture shows to be 100% from 4500to6000
but whats weird is it showed a slight spark knock from 2500to4000 and computer retarded timing down to 26@2500, 21@3000 and 3500,and 27@4000.Yeah the b-came is pretty wicked with this setup,the machine shop who did all my machine work picked out a custom lunati for my motor and it was nearly identical to the B so i just opted to save a 120$ and go with the B.And man does this baby lope Hard!
 

LXMiker

Founding Member
Feb 7, 2002
159
0
0
Good ol' Wisconsin
Jan 9, 2004
#6
  • Jan 9, 2004
  • #6
1bad89gt

i am curious what you run in the quarter mile.............

please tell me if you know..........
 
1

1BAD89GT

New Member
Jan 2, 2004
87
0
0
Oklahoma
Jan 10, 2004
#7
  • Jan 10, 2004
  • #7
LXMiker said:
1bad89gt

i am curious what you run in the quarter mile.............

please tell me if you know..........
Click to expand...

I only go to run this motor once before the season end...Ran a 13.07@106mph
 
1

1BAD89GT

New Member
Jan 2, 2004
87
0
0
Oklahoma
Jan 12, 2004
#8
  • Jan 12, 2004
  • #8
Think i may have figured out some of my fuel problems took it back to my machinist shop today and we ran a few pulls with diffrent fuels and once i got up to 101 octane in the car the spark knock disappeared through the mid rpm range and produced a tad bit more HP....So basically i can run 93 during the week back and forth to work but on play days i need to break out the 101 octane
 
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