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JEFF69Z28
08-23-2010, 10:05 AM
CURIOUS,IS A BIGGER GAP BETTER,WHY DO SOME RUN SMALL GAPS AND OTHERS LARGER GAPS?

cepx111
08-24-2010, 08:37 PM
The wider the gap the more resistance and the harder the ignition has to work to fire the plug.

A smaller or narrower gap will actually have a fatter spark kernel than a plug gapped wider.


On high compression motors on gas I run between .028 .032

Cp

JEFF69Z28
08-26-2010, 04:54 AM
The wider the gap the more resistance and the harder the ignition has to work to fire the plug.

A smaller or narrower gap will actually have a fatter spark kernel than a plug gapped wider.


On high compression motors on gas I run between .028 .032

Cp
I HAVE ABOUT 11.50 TO 11.75 IS 45 TO MUCH

chevyfireball
08-26-2010, 06:23 AM
45? What is your motor? I run 20-25 on a 632 nitrous motor.

JEFF69Z28
08-26-2010, 06:58 AM
45? What is your motor? I run 20-25 on a 632 nitrous motor.
.045,GAS MOTOR 406 SBC

zipper06
08-26-2010, 09:22 AM
I run NGK 8's or 9's with gas or alcohol, if i'm running the V-gaps i set them at .022, gas or alcohol, if i'm running the ES version (flat tip) i set them at .025. All use MSD ignition. In my opinion .045 is way out of range. I know that the old HEI setups GM called for .040/.045, but with multi-spark-discharge aka MSD you'll get much better firing of fuel charge setting them at less than .030.

JMO

Zip.

cncmotorsports
08-26-2010, 05:28 PM
We see .035 to .040 gap makes peak power on most small blocks. If your using a mag then lower to around .025

JEFF69Z28
08-27-2010, 01:34 AM
HOW COME MSD CALL'S FOR .040-.050? USING A 6AL OR 6AL-2

JEFF69Z28
08-27-2010, 03:10 AM
I run NGK 8's or 9's with gas or alcohol, if i'm running the V-gaps i set them at .022, gas or alcohol, if i'm running the ES version (flat tip) i set them at .025. All use MSD ignition. In my opinion .045 is way out of range. I know that the old HEI setups GM called for .040/.045, but with multi-spark-discharge aka MSD you'll get much better firing of fuel charge setting them at less than .030.
DO YOU THINK NGK 7'S ARE TO HOT?

JMO

Zip.

zipper06
08-27-2010, 09:15 AM
I think the 7's are more of a street application on pump gas. i run NGK 8's in my 377" on alcohol, and we run ES8's with a pump gas 468 b/blk shooting 200 shot of nitrous. I run NGK 9's in my blown alcohol sm/blk. I think the 8's would be better for your engine.

JMO

Zip.

cncmotorsports
08-27-2010, 11:19 AM
What heads are you using ?

JEFF69Z28
08-28-2010, 02:37 AM
What heads are you using ?
AFR 210 FULLY RACE PORTED BY AFR

cncmotorsports
08-31-2010, 06:34 AM
What heads are you using ?
AFR 210 FULLY RACE PORTED BY AFR

Use NGK5671A-8

Gap to .040

rich970
09-13-2010, 03:11 AM
what plugs for indy 440-1 with 15 to 1 comp. could i use ngk R5672A - 9 OR 10 or stay with the R5672A- 9 or 10 thanks Rich

cncmotorsports
09-21-2010, 02:52 PM
what plugs for indy 440-1 with 15 to 1 comp. could i use ngk R5672A - 9 OR 10 or stay with the R5672A- 9 or 10 thanks Rich
Try the -9 and see how they work, if they fowl out easy, go to the -8
I'm not familiar with the indy heads as for what reach plug they take.