Originally Posted by 1of40
Remember, don't look at the 4.6 vs 3.9 or 4.0 marketing name plates. Take a look at the true performance variances and ask yourself if overall it is worth it. Seems like the failure rate on 4.6's vs the 3.9 or right 4.0 should also be a factor used in the decision process.
Which means understanding the block in question's history and determining build plan-I.e. a drop in solution with accompanying price tag may not be as intelligent as a 3.9 block reconditioned with 4.6 internals...or a simple 4.2 drop in w/cam and such.
Likewise the leap to diesel is best one done after a careful look at cost/benefit, pro/con, and intended endstate-simply put a 300 TDi is a long way from optimal for many people despite its allure at times.
For petrol options I return to the suggestion of reaching out to Randy Williams to discuss 3.9, 4.2, or what he has cooking in the 4.6 realm.