Answers about my 17 mpg in my Burb.

[68 Suburban]

How about 0w10 for a race engine...lol

http://www.longrider.com/racing.htm

[68 Suburban]

I will start by saying this is from an Amsoil Site, so take it with a grain of salt:

Roger Vinci was a Valvoline dealer using their DuraBlend Motor Oil. Roger has always recognized the advantages of using synthetic oil in racing but always believed that synthetic oil leaked or contributed to a loss of oil pressure. The only way he would consider becoming an AMSOIL account was to prove it to himself by installing AMSOIL in his personal Corvette and running the car on the dynamometer. He installed Series 2000 0W-30 in his personal ZR-1 Corvette.

After switching to AMSOIL Series 2000 0W-30 and a Super Duty Oil Filter, he immediately noticed the piston slap noise was cut in half and the lifter noise was 100 percent gone. He was also very surprised by the lower oil temperature and an increase in oil pressure!

The ZR-1 was then put on the Dyno. The results: A three horse power gain over the Valvoline DuraBlend, plus another eight horsepower by switching the K&N Air Filter out for an AMSOIL 2-Stage Air Filter. That’s an extra eleven horsepower!


http://www.1st-in-synthetics.com/racing.htm

[lukecp]

Here is my combo and gas mileage:

'72 C10, LWB fleet, 20k mile rebuilt 350, 8.5:1 compression, RV cam shaft (204/214 duration, .420/.442 lift), edelbrock performer intake, edelbrock #1406 carb jetted 6% rich, stock HEI, plugs gapped at .045, heddman 1-5/8 headers, dual 2.5" exhaust pipes and 40 series Flowmasters, stock TH350 tranny, and a 3.07 open rear end.

Around town, i average 11mpg. On the highway, i get 12.5 mpg with a load of furniture in the back.....empty it might hit 13mpg. When i had a quadrajet on the truck, i was getting over 13mpg with mixed city/highway driving, but it kept giving me fits so i replaced it with the edelbrock. I tried running the edelbrock with stock jetting, but it was too lean. The truck would surge, and pop sometimes. It runs great with the 6% richer metering rod change. I think it is running a bit rich, since if i open the 4barrel whoever is behind me says it puffs black smoke a bit .

I am putting on a new set of heads with 64cc chambers, and this should bump my compression up to around 9.7:1. Any idea on how much this will increase my gas mileage?

[Baradium]

Originally posted by 68 Suburban
Your not serious? Todays trucks and cars engines will last a lot longer than any car and truck engine from the 60's if the all conditions are the same.

You mean to tell me that you would rather run dino 10w40 rather than synthetic 5w30? If you think that 10w40 is giving you better protection, go for it.

By the way the new Corvette calls for Synthetic 5w30.

I don't know about the engines, but I know the cars themselves won't

And I'll put my 345 against any of todays light car and truck engines. It's just built to last longer. I don't see any engines being built today for the light car and truck market where it's considered bad luck if your engine only makes it to 300k miles between rebuilds (or opening the engine up internally period), the only exceptions I see are the Cummins and the Powerstroke, but those start getting past light trucks as both those companies designed those engines for much rougher usage than a light vehicle.

Come on, there are engines today that don't even use timing chains, they use timing BELTS. And if you lose a belt you get valve interference with the pistons which means big $$$.

I would go synthetic 5W-40, maybe 10W-40. Not telling you I'd run dino 10W-40 before Synthetic 5W-30. I'm telling you I would (and will) use synthetic 5W-40 or 10W-40.

Do you really see cars and trucks of today still driving 40 years from now? I see cars and trucks from the 60's still running around while the cars and trucks are today are dying off. Anything today that uses an engine designed recently won't last that long. A corvette IIRC still basically uses a 350 block. That engine is pretty much the same as it was when it was introduced. There isn't much difference.

[68 Suburban]

We were talking engines and the effect of lighter oils, and not how cars are built. Your original argument is that todays engine would not last like an engine from 35 years ago. The assumption you made was basically because of the lighter weight oil that is used today, the engines won't last.

Not only does the lighter oil improve mileage, it also disipates the hotter running engines today than the heavier oil that use to be used.

Oil has no effect on timing belts, how a car/truck is built, etc. So this is way off from the original discussion.

As for todays car. My dads past 3 cars:

85 Delta 88 307 450,000 miles and still running great before we lost track of the car. Engine was never touched.

92 Delta 88 3.8 engine 290,000 and still running great before we lost track of the car. Engine was un touched.

99 Delta 88 3.8 engine 180,000 miles and he is still driving it. Engine is un- touched.

I think that adds up to 920,000 miles over 18 years and never an engine related failure. He runs dino oil, but is religious about changing it.

I have driven god knows how many vehicles and have never had an engine related failure. I replaced the engine in my burb when I got it because it was leaking like crazy and was tired.

Out of all the cars that my family has had since I can remember, we never had an engine failure except one, and that was my Mom's 1970 Duster with a slant 6. It wasn't the cars, or the oils fault, it was my moms fault for not changing the oil.

[tom hand]

In my opinion there are only 2 kinds of oil...clean and dirty. If you keep a motor full of clean oil it will last a long time. As far as the lighter weight oil goes, I would want to take a good hard look at the clearances run inside the newer motors that were designed for the lighter oils. I haven't checked but I kinda think they have tightened a few of them up. On the great gas mileage you are getting from the burb, I would like to know if you have ever had your speedo checked. Even something as small as running non-stock size tires will throw off your speedo off and then your gas mileage means nothing. I really find it hard to believe you are getting that mileage without overdrive since GM can't do it. I would bet a dollar to a dounut your speedo is off "helping" your mileage. I really am not trying to start anything, it's just when I hear somthing I really have a hard time believeing I am suddenly from Missouri

[68 Suburban]

My speedo is actually 10 percent off because of larger tires. That has been taken into consideration. Also, I have figured the MPG many of times on trips between known distances. Also, I have checked my speedo with the speedo check markers coming out of San Diego on I-8 heading east. I have done my homework non-believer....lol

I also have a witness from the board who witnessed my MPG on a trip to Kansas that I took with him to pick up a vehicle.

[68 Suburban]

oh, I also had my brother the cop, run some radar test on my truck when I went back to Chicago. That also confirmed my speedo is 10 percent off. If it says 60, I am going 66.

[jku72]

I dont use the speedo to calculate mileage. I use known distances, whether its mile markers, or using a seperate new car to measure. I use the amount of gas I pump as read on the pump, but a single pumping could be off as well, so I take the mean of several fill ups.
I got 18 on my recent trip from central Maine to Conneticut. When i was driving across country, On the plains I got 19.8, but my trip average was 18.1. That figures in my Montana driving, where I soon figured out that driving 80-85 with a 1 7/8ths single exhaust was choking me, during that part of the run I got 12.
When i backed off to 65, my mileage went up again.

[Baradium]

Originally posted by tom hand
In my opinion there are only 2 kinds of oil...clean and dirty. If you keep a motor full of clean oil it will last a long time. As far as the lighter weight oil goes, I would want to take a good hard look at the clearances run inside the newer motors that were designed for the lighter oils. I haven't checked but I kinda think they have tightened a few of them up. On the great gas mileage you are getting from the burb, I would like to know if you have ever had your speedo checked. Even something as small as running non-stock size tires will throw off your speedo off and then your gas mileage means nothing. I really find it hard to believe you are getting that mileage without overdrive since GM can't do it. I would bet a dollar to a dounut your speedo is off "helping" your mileage. I really am not trying to start anything, it's just when I hear somthing I really have a hard time believeing I am suddenly from Missouri

A lot of newer oils can't use the heavier weight oils for exactly that issue, tighter clearances. So they can take advantage of the lighter weight oils. I still don't think lighter weight oil is a good idea for older vehicles, and you bring up another point. The lighter oil, when used with the higher tolerances of our old engines, means that parts can move around a little bit more. The newer engines use those reduced tolerances so they can use that lighter oil.

Am I making sense?

What I'm trying to say basically is that just because newer vehicles use it does not mean we should in our older stuff.

[68 Suburban]

Originally posted by Baradium


What I'm trying to say basically is that just because newer vehicles use it does not mean we should in our older stuff.

You have said a lot, but have not shown anything to back up what you say, except a 35 year old owners manual.

How many of our trucks have re-built engines with tighter tolerances. Mine does

Hey, run 20w50, it aint going to kill your engine. Neither is my 5w30.

I will bet you one thing. Today's synthetic 0w30 will give you a lot more protection than 20w50 that was the recomended oil 35 years ago.

[Baradium]

Originally posted by 68 Suburban
You have said a lot, but have not shown anything to back up what you say, except a 35 year old owners manual.

How many of our trucks have re-built engines with tighter tolerances. Mine does

Hey, run 20w50, it aint going to kill your engine. Neither is my 5w30.

I will bet you one thing. Today's synthetic 0w30 will give you a lot more protection than 20w50 that was the recomended oil 35 years ago.

Um, I don't run 20W-50. I use 10W-40, and I'll probobly use 5W-40 or 0W-40 when I switch to synthetic, that is if the synthetic does all they claim it does.

[spinning wheels]

Tom Hand has it right. One reason for the lighter engine oil is tighter clearances, both in bearing and piston to cylinder clearances. A heavier motor oil will cause some drag in the crank case. That is why most high performance engines use windage trays or crank scrapers to reduce engine oil drag. As far as using lighter engine oil for better gas milage, it probably doesn't hurt. Just keep the oil clean and watch for oil contamination from oil getting by the valve seats or piston rings.
I have used Amsoil 20W-50 in my air cooled Harley. Put over 3K miles on it, the oil looked very good. Currently I'm useing Mobil 1 15w-50 with 20% Lucas oil stabilizer in my vehicles. This seems to work better than using straight 0W-30 synthetic. I was having too much oil getting by the valve seats or piston rings. Lucas oil has a synthetic oil that they developed with Warren Johnson for his pro stock race car. This stuff is like water, it's a 5 weight, but in reallity its more like a 2.8 weight. But then again, he rebuilds and replaces motors like there's no tomorrow.
One way to make sure your oil is working, is to cut open you used up oil filter when you change your vehicle's oil. Take a good look at the stuff left behind in the filter. This is a comon practice with race teams.
If I'm not mistaken Edelbrock and K&N filters make an aftermarket sensor that reads your air fuel mixture from you exhaust. I have seen Edelbrock's set up on a mule Harley that they do tests on. You will need to weld a bung in your exhaust . Not sure how they calibrated the meter, but they seem to work when trying to jet your carb(s) to your motor.
If anyone is running one of these, I would like to know if they are satified with it.
Has anyone tried the Holley Avenger carbs?
Suburban, are you still running your stock radiator fan/clutch set up?
Is you burb a disk/drum or a drum/drum set up?

[MikeB]

Using a timing light should help even more. I would start with 32 degrees total mechanical at cruising RPM and keep going until I hear detonation, then back off 2 degrees. I'd then go for max vacuum advance without pinging on transition from cruising to accelerating. Spark advance at cruising speeds = fuel economy!

[71-longbed]

Your not serious? Todays trucks and cars engines will last a lot longer than any car and truck engine from the 60's if the all conditions are the same.

did you happen to forget what you typed .... this comment in no way referes to oil ... merely a direct comparison between new and "60's" cars....

[mtdave2]

the way i see it, its not the brake down of the oil that causes the wear. its the particals IN the oil that are causing it. therefor i wish they would spend more time and engergy makeing better FILTERS than oil.

its true synth. oils will last longer, but i change my oil long before the normal oil breaks down. just save yourself the money, get a good filter and change oil ever 3k and you will be fine.

[68 Suburban]

Originally posted by 71-longbed


did you happen to forget what you typed .... this comment in no way referes to oil ... merely a direct comparison between new and "60's" cars....

No, I didn't forget. That was an answer to Baradium that seems to been deleted.

He had said something to the effect that made the insinuation that cars back in the 60's lasted a lot longer than todays cars, and it was because of the heavier oill.

Now with that in mind, re-read my response and it will make more sense. I guess I should have quoted what he said...lol

[71-longbed]

im happily getting 13 mph in town with my 30+ year old, 239k mile engine ... i hope i can pull off 15 in town once the pertronix igniter is in ....

[Low69CST]

Originally posted by 68 Suburban
By the way the new Corvette calls for Synthetic 5w30.

I think that has more to do with Mobil 1 giving Chevy about a million bucks to put those plaques on its cars. The same engines were in Z-28's with no plaques at all. I've heard that Synthetics are much more prone to leaks than conventual oils. Word round the camp fire is the molecules in synthetic are much smaller than conventual, so in older motors they are supposed to leak like crazy. My dad and I had the same discussion after I built my 415 stroker. We've used conventual 10W-40 for years and never had one oil related problem, why change to something unproven?

[71-longbed]

good point ..i've never had any problems with 10w-40

[68 Suburban]

I think you guys are missing the point. I never told anyone not to use 10w-40. The point is that I was told that I should not use a lighter weight oil because the owners manual calls for a heavier oil. I was defending my choice to use a lighter weight synthetic to help with gas mileage and I was not saying someone should not use what ever weight oil they want.

[68 Suburban]

Originally posted by Low69CST


I think that has more to do with Mobil 1 giving Chevy about a million bucks to put those plaques on its cars. The same engines were in Z-28's with no plaques at all. I've heard that Synthetics are much more prone to leaks than conventual oils. Word round the camp fire is the molecules in synthetic are much smaller than conventual, so in older motors they are supposed to leak like crazy. My dad and I had the same discussion after I built my 415 stroker. We've used conventual 10W-40 for years and never had one oil related problem, why change to something unproven?

Where are the facts on this one about Mobil one paying Chevrolet? I don't think you can say synthetic motor is not proven No leaks in my engine. I have head that "leak" theory for years, I have never had a problem. I can only go by what I have experienced and not what I have "heard"

[71-longbed]

i get the point 68 Suburban...
if i had a new rebuilt 350... i'd definately use sythetic oils... but personally im not willing to take the chance of major leaks.... to each his own

peace

[Low69CST]

My support for my little conspiracy theory was that the same decal in the corvette saying "Use only Mobil 1 5w-30" was not included in firebirds and camaros with the same motor. If the oil was so critical to the engines life, I would say they would put the same decal in all 3 cars.

By talkin about the "leak" theory i was just tryin to bring up another topic in the oil discussion that was going on. When I say synthetic isn't proven, I mean between the knowledge my dad and me, we have never used it in a vehicle we kept more than a couple months. Just as you said you can only go by what you have experienced, same goes with us. I had read several articles in respected magazines such as Car Craft, that leakage was more of a problem with synthetics, espcially in rear ends where leaks occur frequently. We have never experienced a problem with conventual oil, so why change?

[68 Suburban]

Again Low69CST, I am not trying to get anyone to change their oil. Where in this post did you get the idea I was telling people to change their oil? The post was about getting better mileage and I was defending my choice of using a lighter oil. If you use a lighter synthetic, it can help your mileage. If you don't care about that, continue to use what ever you want. I was responding to someone that was saying I should not run the lighter oil.

And I am sure Chevrolet would risk their 50 year reputation for 1 million dollars :p You better believe they putting an oil they believe is good.