97TacoDude said:
I just changed out my Denso plugs to Bosch Platinum +4 plugs after 30,000 miles on the Denso's. I almmost feel like I can sense a power increase after changing the plugs. Everybody at the Toyota dealer used to tell me that "you must use NGK plugs man nothing else works" and blah blah blah but the Bosch lugs seem to work great. The engine runs very smooth, develops good power, and I've seen no ill effects from the non-NGK plugs at all. Do people say that you must use NGK simply because that's what the Toyota manual says or does anyone have quantative data to prove it? I hate it when people speak from the wrong orifice!
97TacoDude said:
I almmost feel like I can sense a power increase after changing the plugs.
Is "almost feel" the same as "Barely Notice"

So how much did you ACTUALLY pay for that "almost sensed" power increase?
Here are my main reasons for running OEM/ NGK/ densos in my 3.4
They are cheap (~$1.50) and work.
I've run Bosch' in my older Non-toyota vehicles in the past with out problem-
However- When my brother put some Bosch Platinum's in His truck - He would get intermittent CE Lights - During the few months that he ran them- His engine also was not running as smooth as before he changed the plugs.
When I suggested to Use the OEM / Densos OR NGK - The light went away and engine ran smoother. (Who knows may be he got a bad batch of Bosch or they weren't properly pre-gapped like they were suppose to be)
so my quantiative data :I've observed 100% CE Light triggering with use of Bosch Platinums in the Toyota 3.4L I've sampled-
Where as I have not noticed any negative effects with use of Denso plugs in 100% of the 3.4L's I've sampled- (Larger sample size too)
Personally - I like to stick with what works unless their is an alternative that offers signicant benefits, cost savings and/or has a high benifits : cost ratio