Re: engine oil
hey aggie. here's the story to go with that assessment. my first new car was an 82 dodge colt, made by mitsubishi. optional was the 1600 engine, i had the 1400, at 73 hp. twin stick transmission gave two final drive ratios. on a 4 speed, i had 8 choices, with 2 reverse's to choose from. neat. it's not like you drove it like an 8 spd, but it was cool to have the extra gears to play with. if you were immature, you could put it in first gear, power, as opposed to economy, and set the parking brake. you could light up the front tires for days if you wanted to, and it would drag the back wheels slowly forward. but i wasn't immature......anyway, i used live in windsor, across from detroit, before i moved to toronto. i would drive up to the family cottage on the weekends in the summer, on friday night, late. i would commonly run it at 140kmph, around 87 mph, for several hours to get there. my top speed was just over 150 kmph, or around 95 mph. because of the constant high speed travel, i tried 20w50. i was also checking my economy on every tank, as i tinkered with the tuning to get the best i could out of it. no computer, staged 2 barrel carb. with 10w40 in there, i would get around 37 mp imperial gallon at around 110 kmph. with 20w50, it dropped to around 32. passing power sucked, and top speed, probably the best indicator, dropped to around 82 mph, and it took awhile to get there. it was very noticeable. i really wanted a greater film thickness in the oil, but not at such a high price. i wrote a letter to quaker state, asking if it was ok to mix grades. i told my story. an engineer wrote back. they said it is fine to mix grades, but that they did not expect that i would notice any reduction in ecomomy and power output. B S! obviously this guy had never tested the stuff in this situation. now mind you, the oil pressure this engine produced was very high. i had added my own oil pressure guage, and with 10w40 i had around 60 psi at startup cold. with 20w50 i got around 100 psi, both in the summer. at high speed on the highway with 20w50 it ran high 70's psi. so. i decided to use a blend. 1 litre of 20w50, and the other 3 were 10w40. power and economy came back. and i still felt better that i was adding just a bit more protection. lots of words, but a worthwhile story. where you live, i'd personally probably go with the half and half mix in the summer for straight highway use, but maybe 3/4 20w50 for off road use. just my opinion of course. i hope this story helps you to choose the best grade for your situation. best of luck neighbour!