- Joined
- Jul 21, 2021
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- Sf Bay Area, CA
- Vehicle(s)
- 2022 Bronco 2dr BL SASQ, & 1975 Bronco Ranger
- Your Bronco Model
- Badlands
I completely agree!!!! COKING on the intake valves has been addressed with the advent of port injection.The catch can is for gas engines that are direct injected. The issue is that since the gas is injected directly into the cylinder the blowby oil from the crankcase that is routed into the intake can cause a carbon build up on the back of the intake vales, since there is no gas to wash it off. Previously, in port injected engines gas was injected into the intake and so the gas cleaned the back of the valves. This hasn't been an issue on diesel engines.
After 2001 (I think) our CA smog tests are simply an inspection and checking for codes. If the check engine light isn't on, then you pass the smog check. I wonder how many smog techs are going to check carefully enough to see a catch can. Who knows.
BTW, the 2.7 was designed with the gas injected in the port right in front of the valve, for this reason. No catch can or carbon build up on 2.7 motors.
However.....
Another thing to consider is.... this turbo charged 2.7 puts positive pressure into the manifold which temporarily shuts down the vacuum required to pull vapors from the PCV. Then, at the same time, when the Turbos spool up (PCV shut off) the fresh air breather (which was intentionally routed right by the turbo intake on the drivers side) stops being a breather but rather an exit for pressures (blow by) building in the crank case. In reality, the turbos (when spooling) pull oil vapors out of the crank case via the breather. This in turn, coats oil vapor from the turbo to intercooler then to the manifold. YOUR INTERCOOLER WAS NOT DESIGNED FOR THIS. Its function is to cool clean filtered air pressurized (heated up air)by the turbos then sent to the manifold. Over time, sucked in crank case breather oil vapors… will eventually cake on to the intercooler cooling veins, thusly reducing heat transfer. Its function to cool down the pressurized hot air is minimized. Similar to a radiator that's core has been plugged up with rust and other debris over time. It greatly reduces it's effectiveness to cool.
So the point of port injection is very relevant to stop coking on the intake valves, and is a major improvement.... however the engine would still greatly benefit from minimizing crank case oil vapor (fuel, oil, water vapors) finding it's way to the intercooler (and other intake areas).
Something to think about?????
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