Re: motor oil and gas - recommended?

[DMCVegas@xxxx]

As far as gasoline is concerned, my car has never run well on 87 
octane. The engine is sluggish, and accellerates very poorly. 89 she 
does ok on, and is alright for commuting. 92 REALLY brings the engine 
to life. Granted I'm still not going to win drag races at the track, 
but the engine response is much quicker. While you may not ever go 
that fast, when running 92 octane I can usually get the engine around 
2-3K RPM's faster in 5th gear @ 100mph+. Although I'm still looking 
for a longer, isolated stretch of highway to see just what the engine 
will top-off at. While on a personal note, the best fuel I've found 
to run in my car is Sinclair 92 octane.

As far as oil is concered, I doubt there will ever be a 100% clear 
answer on this. Many people perfer 1 type to another. So to stay as 
unbiased as possible, I will omit brand names. And to reduce 
confusion, I will also ommit the centigrade conversions. As an 
example, I myself run 20W/50 in my car. In the DeLorean owners 
manual, it specificly states 20W/50 is for 60°+ Note that there is no 
limit on the temp.

The next range is 2°to102°. Oils here are reccomended are 10W/50, 
10W/30, 10W/40, 15W/40, and 20W/40. My guess here is that these grade 
types are listed from coldest temp, up to the highest. Here you can 
also see that the range has a limit of 102°. Since my geographic area 
exceeds this limt, I use a heaver oil. Yes you will not find some of 
these multigrade mixures on the shelf at your local auto parts store. 
But they do still exist.

Lastly, for the -2°to-21° range, the manual reccomends to use 5W/20, 
or Single Wieght 30. It also notes that these wieghts shouldn't be 
used when the temp is consistantly above 32°F. Since most, if not all 
D's stay home durring these types of weather conditions, this last 
scale probably won't apply to anyone.

Now on more of a personal, kind of flip side to this debate. Most new 
cars I've seen (GM specificly) reccomend using 5W/30. I always looked 
at those and though the wieght was WAY too low. Especially on the 
cars with V-8 engines! But to follow my own advice, guidelines set by 
the manufacturer should be followed for the specific engine. Remeber, 
the PRV uses hydrolic tensioners for the timing chains, while other 
engines don't. What is good for 1 type of motor, isn't always good 
for a different type. But even my old Ford 5.0 truck was set to 
almost the exact same guidelines as my DeLorean is.

Anyhow, just my 2¢

-Robert
vin 6585



--- In dmcnews@xxxx, Soma576@xxxx wrote:
> Hey all,
> 
> i was going though my shop manual today and noticed that it 
recommends 91 
> octane gasoline for the car. i've been using 89 octane. yes i 
know what the 
> rating means, but is there a good reason i should be using 91 
instead of 89?
> 
> second, it recommends some pretty heavy motor oil. it says that 
15w40 is a 
> recommended weight! i've done over a thousand oil changes at the 
part time 
> job i work at, and i've never put oil like that in a car - the only 
engines 
> that use that (Rotella, usually), are big diesel pickups!! 
it's 'the diesel 
> oil'. what do most people use? it says regular 10w30 is ok but 
only in cold 
> temperatures.
<SNIP>