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Spark Plugs



Anyone else have this problem? My car seems to break up up 4,000rpms... *Suspecting carbs*. I have dual quads and a full race cam in my close to stock L-48 in my 76 stingray. Heres the question. G-teched it consistantly at 7.13 0-60mph, and 15.89 1/4 mile =*( (Better than the 19's it was running before my add ons). I have hookerheaders/sidepipes, 700r4 trans, 2500 stall speed, and a full race cam that kicks in like 3200rpm. This was with the aircleaner on, and Stock sparkplugs (AC-Delco 45TS gapped at .45) I just changed the plugs to Autolites, went one range cooler 25. I gapped them at .35 From what my dad was telling me, that makes it burn hotter, resulting in more power. It worked with my 69 Firebird. Well, I feel more power, it breaks up more on the lower end now too, and can't get below 8.01 0-60mph, 16.00 1/4mile with the airclearner off to let it breath a little. I have not had a chance to run it with the cleaners on again. It does have an electronic ignition, unlike my firebird. Does electronic ignition need a bigger gap?


Active member
Sep 9, 2001
Mentor, Ohio, Lake
84, primer /69 brite red /66 red / 60 hugger orang
It sounds to me that your Ignition is not right what kind are you running. Are the plugs real black and what type of advance are you running, Being and total. What valve springs are you running open pressure and closed and what are the specks of the cam, duration @ .05 and total lift.


Well-known member
Dec 27, 2000
Florence, SC (Timmonsville SC)
71 War Bonnet Yellow VERT 71 BH Blue CPE (SOLD)
/page62 ... Yes.

Dads are pretty smart ... most of the time. If all components of your electronic ignition system are in A1 shape ... open your plugs back up to 0.045" ... you'll get a more complete burn.


I need to get my timing gun back from my friend, but, the plugs that I took out were burned greyish white, with the exception of the drivers side front plug, it was black. I took the new plugs out, and reggapped them to .45. Drivers side front plug once again, was brown now, and the rest had no color. *only 20 miles on them* The valve springs are stock. Forgot the specs of the cam =( .480 lift is all i remember. I may try going up a range warmer now. Get this..
15.89 ¼ mile @ 87.7mph
7.13 0-60mph *AC Delco 45TS with aircleaner on*
7.53 0-60mph *AC Delco 45TS with aircleaner on, no brake torque*

16.00 ¼ nuke @88mph *Autolite 25’s .35 Gap*
8.38 0-60mph *without air cleaner, brake torque*

7.90 0-60mph *with air cleaner, brake torque*
7.43 0-60mph *with air cleaner, no brake torque*

15.80 ¼ mile @87.9mph *with aircleaner regapped at .45*
7.10 0-60mph *with aircleaner regapped at .45*

15.95 ¼ mile @86.1mph *brake torque, regapped at .45*
7.41 0-60mph *brake torque, regapped at .45*

With the autolite spark plugs in, I am consistantly getting better times without using the stall speed... Weird. AC picked up .4 consistantly. Autolites are losing .3-.5 consistantly using stall speed... Strange since the cam kicks in at about 3200, you would think that using stall speed would be better times. Unless, these autolites are too cool and arent' burning right while being brake torqued?

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