Good plug and proper gap for fuel inj 347 stroker?
04-22-2007, 03:53 AM
#1
Mustang Nazi
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Good plug and proper gap for fuel inj 347 stroker?
I think I need a little hotter plug for my stroker. Plugs were very black. What is a good plug and the proper gap for a N/A fuel injected 347 stroker? THANKS
04-22-2007, 04:32 PM
#4
Mustang Nazi
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RE: Good plug and proper gap for fuel inj 347 stroker?
ORIGINAL: ZachW04Stang
How rich are you running it. Might want to try as low as .040 maybe even .035. Also whats your compression?
How rich are you running it. Might want to try as low as .040 maybe even .035. Also whats your compression?
04-22-2007, 04:38 PM
#5
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RE: Good plug and proper gap for fuel inj 347 stroker?
I run NKG's with .040 - .045 gap at 10.2-1 compression
Autolites or NKG's with .040 gap should do you right.
you need to check with head manufacturer to confirm right spark plug number to use.
The higher compression can blow out the spark if gap is too big.
.050 for lower compression
.040 for higher
.035 for boost.
give or take
Autolites or NKG's with .040 gap should do you right.
you need to check with head manufacturer to confirm right spark plug number to use.
The higher compression can blow out the spark if gap is too big.
.050 for lower compression
.040 for higher
.035 for boost.
give or take
04-22-2007, 04:45 PM
#7
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RE: Good plug and proper gap for fuel inj 347 stroker?
If your plugs are black it sounds like you are running rich.
Have you checked air/fuel ratios? Dyno tune?
Might be fuel problem rather than a plug problem
Have you upgrade the coil for hotter spark?
Dont need a full MSD box but do need a high volt coil
Have you checked air/fuel ratios? Dyno tune?
Might be fuel problem rather than a plug problem
Have you upgrade the coil for hotter spark?
Dont need a full MSD box but do need a high volt coil
04-22-2007, 04:46 PM
#8
Mustang Nazi
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RE: Good plug and proper gap for fuel inj 347 stroker?
ORIGINAL: r.barn
If your plugs are black it sounds like you are running rich.
Have you checked air/fuel ratios? Dyno tune?
If your plugs are black it sounds like you are running rich.
Have you checked air/fuel ratios? Dyno tune?
04-22-2007, 05:25 PM
#9
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RE: Good plug and proper gap for fuel inj 347 stroker?
black plugs are usually a big sign of running SUPER rich.
take it up to a dyno and just do a couple of A/F pulls and see what
she's reading out at. I bet thats your problem
What do you have fuel press. set at?
What size injectors?
take it up to a dyno and just do a couple of A/F pulls and see what
she's reading out at. I bet thats your problem
What do you have fuel press. set at?
What size injectors?
04-22-2007, 05:29 PM
#10
Mustang Nazi
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RE: Good plug and proper gap for fuel inj 347 stroker?
ORIGINAL: r.barn
black plugs are usually a big sign of running SUPER rich.
take it up to a dyno and just do a couple of A/F pulls and see what
she's reading out at. I bet thats your problem
What do you have fuel press. set at?
What size injectors?
black plugs are usually a big sign of running SUPER rich.
take it up to a dyno and just do a couple of A/F pulls and see what
she's reading out at. I bet thats your problem
What do you have fuel press. set at?
What size injectors?
