mcodecuda
Senior Member
Which NGK spark plug do you use in your 440 on the street?
Thanks, the speed shop gave me R5670-8’s and I’ll exchange them for R5670-6’s.NGK R5670-6
We settled on NGK R5670-5 and they will be here Tuesday.
interesting , since ngk`s go the other way on heat range !R5670-5 on the street were too cold a plug and my car did not like them in the cooler weather in the spring and fall here in Ohio.
Which NGK spark plug do you use in your 440 on the street?
NGK's seem to work better in my Mopars than other plugs. My buddy mentioned that to me once, I switched and love them.
I forget the exact plug numbers I have now, but I run two different heat ranges on 3 cylinders in my RB to get the same 3 to 4 thread discoloration from the end of the plug downward on all cylinders.
I started doing this after reading the 4 Seconds Flat plug reading write-up.
Spark plug reading can be complex and sometimes frustrating task this page will help make it easier and the results rewarding
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THATS LIKLY BECAUSE OF THE UNEQUAL FLOW IN IN UR INTAKE RUNNERS !
Yes, I suspect it is too. These old intakes do have a significant port to port spread. Even though this one has been heavily massaged internally by Hughes and each ports flows a lot more and than they did stock, it still suffers from significant variations from port to port. They are closer to each other in terms of flow now, but there is still marked spread on several ports.
I would like to send a fresh intake to Wilson Manifolds and have them give it their max effort, but I've been to lazy to pull my current intake, bolt on the new one to get the head ports marked onto it and then replace the current one so the car runs while they do it.