shaker56

I have a 2004 4.6 2V engine bored 20 over custom grind cams stock heads just planed ford racing intake BBK 78 mm throttle body and the crank was cut to go with the grind of the cams it is supposed to be a stroked 288 the problem im having is at full throttle it has terrible spark knock the guy that built the engine said it needed to be tuned so I got it tuned at a place in New Jersey they said it is tuned now but I still have the spark knock can the cams be off a tooth im wondering if anyone had a problem like this any help would be appreciated I also tried two colder plugs and only run 93 or 94 octane in it

Z28KLR

Doubt that the cam sprockets are off by a tooth or two. Your problem would likely be a lot different if they were.

There could be a bit more to it, but if you're running 93 fuel and still got pinging at wot then likely spark timing is a bit too advanced. Put stock heat range plugs back in and tell the shop in NJ to put it back on the dyno and make it stop detonating.

WhiteFoxGT

Sounds like you need a new tuner

jwog666

^^^^^^^^^^this +10000000000000