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-   -   BBC spark plug gap help (https://www.racingjunk.com/forums/showthread.php?t=33700)

duby05 08-11-2013 07:23 AM

BBC spark plug gap help
 
I am currently running .044 on NGK R44 or R45 have pro comp aluminum heads 10.5:1 comp. Accel high performance HEI distributor with accel 8.5mm plug wires. I was gapped at .050 and ran .6 slower than with current gap. Question is will I see better et with a smaller gap? Also looking to get a larger carb. Any opinions?

Swiley383 08-11-2013 07:55 AM

I ran my big block at0.35 it was 9.5 to1 with iron heads and a 850 carb

roadkill2 08-11-2013 10:16 AM

I'd say .040 but it has a lot to do with Compression ratios, Combustion Chamber configuration, and timing, as well as what fuel you're using . .

Just another one of those things that make each of our engines "a little different" . .

duby05 08-11-2013 10:54 AM

I'll gap my spare plugs at .040 and swap them out at the track to see what happens. I'm running 110 fuel only.

bjuice 08-12-2013 05:33 PM

Re: BBC spark plug gap help
 

Originally Posted by duby05
I am currently running .044 on NGK R44 or R45 have pro comp aluminum heads 10.5:1 comp. Accel high performance HEI distributor with accel 8.5mm plug wires. I was gapped at .050 and ran .6 slower than with current gap. Question is will I see better et with a smaller gap? Also looking to get a larger carb. Any opinions?

Whaaat ? you have.6 slower...thats 6/10ths.. Ain't No way !!! .daym mine didn't slow down that much after breaking push rod wiping out cam lobe dropping a cylinder.....do you mean .006 ????? :shock:

duby05 08-12-2013 07:04 PM

Nope I meant .6...first pass ran a xx.61 something didn't feel right and only thing that had been changed was plug gap, pulled plugs re gapped and ran xx.01

Swiley383 08-13-2013 10:20 AM

I think you may have had a diffrent problem that was fix when you pulled the plugs like a bad connection/ connections on your plug wires. how much did your MPH drop off?

duby05 08-13-2013 06:23 PM

Only a few mph

bjuice 08-14-2013 06:06 AM


Originally Posted by duby05
Only a few mph

a few MPH is a lot of ET....1/2 second or 2 mph in my Outlaw car is 3 car links easy... thats a Big Loss !

duby05 08-14-2013 10:43 AM

All is well right now. Going to see what a .040 gap does for me


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