No worries mate, I'll be happy to give it a try. That sludge thing is amazing, the company car I drive is a factory E Gas model, i.e., it runs on straight liquid propane gas, (LPG) and has never seen gasoline.
The exhaust pipe has no carbon in it at all, to the point where it's showing signs of rust inside, and I can pull the dipstick after 20,000 Km (12,000 miles) and that oil looks just like it did the day it was poured into the engine.
Are there LPG conversions available for your Limo's? The taxi industry here has been using LPG for 30+ years, and I remember talking to a cab owner/driver all those years ago who told me that he used to change his oil every 5000 miles when his cars were running on gasoline, so after the LPG conversion he checked the oil at 5000 and it looked new, so he left it for another 5000, and it still looked new, so he didn't dump it out until the 20,000 mile mark, where he took a sample to an industrial chemist who tested it and told him that it had no carbon contamination at all, and had lost none of it's viscosity. He upped his oil change intervals from 5000 miles (weekly) to 50,000 miles, (monthly) and the cab I was riding in had done 500,000 miles on the one engine (a Ford 6 cylinder crossflow) with no major signs of wear.
Over here LPG is less than half the price of gasoline, and while not as efficient (you lose a small amout of horsepower and gas mileage goes down a bit) it's still a nice sheap alternative to gasoline, and it's much kinder to your engine (and the environment) than gasoline. Cheers, Terry.
