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Discussion Starter · #1 ·
The paperwork supplied by Trick Flow calls for Autolite 3924s, but this should be the stock heat range. What do you guys use on a boosted 5.0 with Trick Flow TWs?

Beer Swillin' *******
1,369 Posts
Colder plugs can foul out in a lower compression NA motor. This whole cold plug thing relates to how quickly the plug can transfer heat to the cylinder head. A colder plug transfers heat more quickly and a hotter plug retains more heat. For more info go here:


The best bet, IMO, is to run the coldest plug you can without fouling. For me, this is the NGK FR5. I have run the Autolites & they ran good, but I like the NGK's better. I have no dyno proof, but I would swear that the car runs faster & better with the NGK.

For 8psi of boost on a stock block 5.0, maybe the FR6 NGK would be the way to go.
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