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I gapped the plugs to .054 per my emissions label.....It specifies right on them. Torque should be 28 lbs dry. You will be good to go.
Unless there's been a change in torque specs between the 99 5.4 and the 97 ... my 97 5.4 calls for 12 to 14 ft. pounds torque.
Or to be more specific, 80.3 to 178 inch pounds .. page 303-01c-235
14 is a good middle number, it seems almost ever year and engine is a bit different I have seen as low as 11 and I think I have seen 17 on the high end but never anything close to 28.
Do more research and form your own opinion.....they changed it from the 14lb range with antisieze to the 28lb range without antisieze after all the blowout issues. That was part of the problem.....the plugs were coming loose and getting blown out.
Do more research and form your own opinion.....they changed it from the 14lb range with antisieze to the 28lb range without antisieze after all the blowout issues. That was part of the problem.....the plugs were coming loose and getting blown out.
Plugs were getting blown out on the old NON-PI heads, specifically on the Lightning. Under boost, the plugs were pulling the threads out of the heads. In 97, 98, and early production 99 heads, they only had 4 threads. From late 99 until the 3-valve came out, the PI heads have 8.
That doesn't mean the torque spec doubled. We are still dealing with aluminum heads.
Plugs were getting blown out on the old NON-PI heads, specifically on the Lightning. Under boost, the plugs were pulling the threads out of the heads. In 97, 98, and early production 99 heads, they only had 4 threads. From late 99 until the 3-valve came out, the PI heads have 8.
That doesn't mean the torque spec doubled. We are still dealing with aluminum heads.
What constitutes the engine being a late 99? My truck is a 1999 model and was built in August of 99.
It's 28ft-lbs.....Not 200. Aluminum heads can easily handle 28
Originally Posted by Crash!
Plugs were getting blown out on the old NON-PI heads, specifically on the Lightning. Under boost, the plugs were pulling the threads out of the heads. In 97, 98, and early production 99 heads, they only had 4 threads. From late 99 until the 3-valve came out, the PI heads have 8.
That doesn't mean the torque spec doubled. We are still dealing with aluminum heads.
What constitutes the engine being a late 99? My truck is a 1999 model and was built in August of 99.
I would Consider that a late 99 as the probably starting making 2000s before the end of the year.
My 99 Was built in in october of 98. Obviously An early model and Spark Plug Number 3 Just blew out on me now. Been waiting for it to happen for a long time.