Head porting on 3.0
#2
Thats probably the bare head. You might have to get a shop to set it up with guides, valves, shims and such. Gets to be pricey. Make sure what the 350 includes. I had mine done and added the reground cams too. The difference was not really good untill I also added a full 2.5" exhaust from the exhaust manifold on the engine back. Then there was a power boost mostly from 3k on up. Still not as fast as a 3.4L, but its a better performing 3.0L If I was to do it again, I would not do it due to the overall cost to me. If 350 is for the complete setup head, then yea, thats makes a bargan, but I think that may be just for the bare head itself. Thats what I did. Then a local shop charged me an arm and leg to set it all up again.
#3
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From: Fort Worth/College Station, TX
I was more interested in if the 33hp claim is correct. I know 350 is only for the bare heads, but between me and some of my gearhead friends we could rebuild the heads.
#4
It will help HP but you may lose a bit of torque.
I am not surprised high RPMs showed a difference but most of your driving uses torque.
I wouldn't do it since the 3.0 ia already very lacking in that dept.
I am not surprised high RPMs showed a difference but most of your driving uses torque.
I wouldn't do it since the 3.0 ia already very lacking in that dept.
#5
I cannot verify the figure as I have not run Dyno tests. I can tell you that where a 3.4L 4 runner can hold 70 mph at 2000 rpm on a grade close to my house without shifting or loosing speed, the ported 3.0L cannot. It turns around 2600 rpm and looses speed untill it downshifts to get back to speed. Wheather this translates into a 33hp increase or a 20 hp increase, I cannot tell you. I can tell you this, the exhaust will need to be opened up to realize the full benifit of the power increase.
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