Monday, March 03, 2008

Changing my driving habits

(136,600 miles)
I am now going through - or mostly done with - my 2nd mild winter here in Southern California running my Jetta on WVO. Last year during the cold spells I started not switching over on the colder days because of my short drive to work and the robustness of my system at the time. This winter I've come to the conclusion, and the practice of, not switching over unless I am in for a longer drive during these cooler months. It is amazing how much the ambient temperature can play.

There is a HUGE thrill in switching over to VO when one firsts convert the car. The idea of driving for free (or very little costs), helping the environment and not playing by the man's rules is a great feeling. But the more I have learned about the process and the fear I have of damaging my engine has made me realize that in my particular situation it is best to just drive on diesel for my daily commute to work, especially during the winter.

My drive to work most days is 8 miles each way. Even though the engine may be at operating temperature there are parts of the engine that are not. I guarantee you that if you were drive your Jetta until the temp gauge read 190º that your IP would still be cool to the touch. It is just not possible to heat the oil to the correct temperature in such a short drive. Even if the oil was a 160º before the IP as soon as it would enter the IP it would drop in temp because the IP would act like a big heatsink and suck the heat out of the oil. The Frybrid HE supposedly solves this problem because it brings the oil in contact the hottest coolant before it is injected.

I have found that if I do several short drives - drive / park / drive/ park - that the heat sink feature can work to my advantage. If I do a short drive and park, the heat from the engine core and coolant lines will radiate the heat to the oil while the car is parked (for a short time, 5-15 minutes). Even though the engine isn't running the oil is being heated as the heat is dispursed. When the car is started again the engine immediately heats up and the oil has absorbed the radiant heat so there is virtually no lost time for the switch over.

The oil tends to get hotter sooner after the switch over if I am doing local driving as opposed freeway driving. I'm assuming this is because of the volume of oil that the engine requires on the freeway is too much for the systems to heat before the complete system is up to temp.

Sometimes I report to a different location that requires me to drive more and I can switch over. I probably purge earlier than needed and for a longer than required period - better safe than sorry. The best scenario, IMHO is one who drives longer distances and waits until the engine is amply hot before switching and then purges correctly.

1 comment:

  1. I agree. I used to switch over as soon as a could, but with a 8 mile drive to town (often it's a quick 16 miles to drop the kids off) I tend to drive veg in the summer, but stick to diesel in the winter unless it's a full 23 mile drive to the city. Oh yeah, I'm in Alaska, and I put a Flat Plate Heat Exchanger (Plantdrive, Frybrid, Omarsales) on ALL my conversions. Nothing transfers the coolant heat better.