Spark Plugs

[mikes67]

Hey Folks! mikes67 back after a little absence. Really need some help. Just got through doing some major tuning on the 402BBC and went through the 750 holley but the thing keeps falling on its nose at 5400 to 5500. Mechanic suggested changing to a hotter plug so i went from the R44XLS ACDelco that was in it to a #5 plug and the car sounds like 3 of the plug wires were left off. I'm going to put the engine specs below because I know someone of you gearheads is going to ask and I want the best help i can get.

396 + .30 = 402CID
540 lift hydraulic cam
10 to 1 compression (.250 dome pistons)
Edelbrock Aluminum Heads
(Performer RPM RECT. Port 6055)
Edelbrock Air Gap Intake
750 Holley

[mikes67]

That is a AC Delco Spark plug rapid fire cross over number from a champion number that Edelbrock says to use but i think it is the wrong plug fro these heads

[mikes67]

Originally Posted by stalkingbear

I'm curious - what is a #5? I'm assuming it is a hotter plug?

Mike
that is what they said when i went to the parts house with the champion number

[mikes67]

Thanks. Sounds like a good place to start. I am taking the #5 plug out and going back to the R44's, I'm going to go ahead and change out the wires, everything else has already been done so this has to be the last thing. I will get those plugs and wires in the motor tomorrow evening, got to work first to pay for that monster. Will let you know the out come on Tuesday or Wednesday.
Thanks

[mikes67]

At least you did respond to my problem. I went back to the R44 plugs and got the same results at 5400 RPM it just falls on its face, I talked to the guy who did the carb work and he said it is probably the valve springs. So i guess that is the next thing, i can still drive it, don't need to get much over 5100 to smoke the blue oval boys HA! HA! got some good friends with stangs.
Stalkingbear thanks for your help and support, its good to know there is some one out there willing to help this old dawg.
Blessings
mikes67