I have a 93 Toyota Pickup 4x4. Currently I average 18.4 mpgs. It's a 5spd, manual locking hubs, 3.0 Liter V6. Unladen weight w/ me in the driver seat is 4060 lbs.
I have taken care of a bad EGR valve and installed a new magnaflow catalytic converter. 100% synthetic amsoil, front to rear. K&N air filter. All non-essential vacuum operated devices are gone. No AC (totally removed to the back of the dash).
I have a JAW (just another wideband) kit from
New Page 1. I'll be monitoring my AFR, EGT's and I may install a MAP sensor so I can monitor that. It can also log RPM & TPS. However, AFR is logged all the time and then there are only 3 optional inputs to choose from. Must choose wisely.
I have looked at the MPGuino and I can probably put it together & use that for data logging as well.
My plan is to lean out the engine. The factory O2 sensor is still installed, that way the ECU does not go into open loop mode. The WBO2 sensor is installed 10" downstream in the cat.
In addition to leaning out the engine, I'd like to advance the timing. Most guys for this toyota that advance timing run it to 15 +-2. Base timing is 10 deg BTDC.
This engine family is prone to a burn #6 exhaust valve, so I'll be installing my EGT thermocouple as close as I can. It happens to be where the exhaust manifolds merge, right next to the #6 cylinder.
Any ideas what an ideal EGT would be? How hot can it get before I have to worry about the valve burning?
I know as you get more lean, it gets hotter, and more advance gets hotter. But after a certain point, it gets cooler.
I will run 2 tanks or so (600 miles) with everything at factory spec. Timing, AFR, idle speed, idle bypass, cold idle speed, etc.
After that, I'll make my changes and log the results.
Would I have to go to a premium fuel to cool it down running more lean & advanced? Would it benefit?
Any savings in fuel is a bonus at 40K miles per year. When I got the truck it was getting 14 mpgs.
Tires are inflated to 50 psi as well.
Thanks,
~ryan