Hmmm, interesting about the exhaust valves on 5 and 6. I have what is probably a dumb question: How are the cylinders numbered on the 3.0? I'm just curious, if they were the rear two cylinders it wouldn't be the first time I've seen some weird things having to do with temperature gradients in engines ranging from burnt valves to massive carbon build up in some while others are squeeky clean.

On that note, temperature gradients like that might even have something to do with uneven expansion maybe making the HG's more vulnerable.

Watch some super charges their engine and bumps up the EGR or something weird to keep the temps down.....

But yeah, anything more on this? It's an interesting thought.

Frank.

1994 4runner, 3.0, auto, 4.88's, 31's, BJ spacers, Coil spacers, air shocks, D-ring anchors, 4Crawler F/R swaybar discos.
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