Oil pressure comparison - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


Performance, Brainstorming & Tuning Talk about modifications, or anything else associated with performance enhancements. Have a new idea for performance/reliability? Post it here. No idea is stupid! (please use Detailing and Appearance for cosmetic ideas)

Reply
 
 
 
Thread Tools Search this Thread
Old 05-27-2003, 03:23 PM   #1
Senior Member
True Car Nut
Thread Starter
 
Join Date: Oct 2002
Location: Genoa, Illinois
Posts: 4,013
Thanks: 0
Thanked 0 Times in 0 Posts
Allmachtige is on a distinguished road
Default Oil pressure comparison

I changed to 20-50 Valvoline VR...er VH....or some 2 letter racing oil this weekend!
Anyway, my idle oil pressure increased from roughly 40 to 75, according to the stock guage. Just for reference so I can get an idea of where I stand, how does this compare to other L27'* out there?
Allmachtige is offline   Reply With Quote
Old 05-27-2003, 05:50 PM   #2
Senior Member
Posts like a Turbo
 
Join Date: May 2003
Location: Oklahoma
Posts: 359
Thanks: 0
Thanked 0 Times in 0 Posts
Kuhl is on a distinguished road
Default

I dunno I still run the factory recommeneded 10w-30 and it gets reallly hot down here, 100 degrees in the summer constantly. I should probably change it, but I am afraid I would jack something up. Any suggestion? 10w-40?
Kuhl is offline   Reply With Quote
Old 05-27-2003, 11:13 PM   #3
Senior Member
Posts like a Turbo
 
Join Date: Jul 2002
Posts: 417
Thanks: 0
Thanked 0 Times in 0 Posts
Azwed is on a distinguished road
Default

Acckhh noooooooooooooo bad.

Get that crap out of there.

I am not going to go into all the technical reasons why 20w50 is bad for 90% of the motors out there but if you really want I can dig some tech data up and put it up later this week. Part of the reason comes down to film strength. The thicker viscosity oil has higher film strength because of its thicker viscosity but that same thick viscosity does bad things to your motor. The thick oil creates extra friction which is bad for tons of reasons. In cold weather thick oil is very bad since it takes much longer to flow to the valvetrain then thinner viscosity oil.

I hear this all the time at my shop when old people still convinced that thicker oil is better put 20w50 or worse monograde 30 or 40 viscosity oil in their vehicles. You start up the car and for several seconds all you hear is knock knock from the crank and then for many more seconds after that stops massive ticking from the valvetrain running dry. If you ever want to hear something really ugly start up a small block chevy with straight 40 oil in 30 degree weather. The motor will tick and knock for a good 15-30 seconds.

If you think you need some extra protection in your motor switch to a high quality synthetic or semi-synthetic. Valvoline, Mobil 1 or my favorite Amsoil are all good choices. Redline is not so good for non-race vehicles that go several months between oil changes. Royal Purple is another synthetic company geared to racers more but I don't know much about them.
Azwed is offline   Reply With Quote
Old 05-29-2003, 12:20 AM   #4
Senior Member
Posts like a Turbo
 
Join Date: Jul 2002
Posts: 417
Thanks: 0
Thanked 0 Times in 0 Posts
Azwed is on a distinguished road
Default

Quote:
Originally Posted by jr's3800
I knew someone explained all of this before... Thanks for stepping in Azwed....

Next time this comes up I'm going to remember you name...

I have ran 10w40 here in Florida in my 95 bonneville... It didn't really seem to make much diffrence... So I use 10w-30 all of the time now... I have never had any trouble...


Yeah in florida you probably won't notice much difference between 5w30-10w40 cause it is so hot. 5w30 and 10w30 are both considred all climate oils anything heavier is generally not an all climate oil.


On a side note isn't 10w-30 better for power and effiency?... I would think that 20w-50 would make the engine less efficent due to the oil being thick, as well as not being able to lubricate the wrist pins, rings and what not like oil should... Toooo Thick..


Yup that is true. Using an oil thicker then 10 or 5w30 is leaving hp and mpg on the table for all but about 10% of the motors out their. I know for a fact that when Mark Martin raced for valvoline they used ordinary 10w30 valvoline synthetic in his car just like you can buy on the shelf. No one here is pushing a motor a quarter as hard as he is.


And on some or most of the new Fords,Dont they require 10w-20 due to the tight tollerances of the engine?...

I do agree though if the switch is a performance minded one I'd go with Mobil 1 or another good quality synthetic oil...
All 2001 and up Ford(except some of the Exploders for some reason not sure why using up NOS i guess), Honda and any Mazda using a ford derived engine are now using 5w20 oil to increase fuel efficency. Ford is mainly doing it to help out their CAFE which, like all domestic manufacuters, is hurt by all the big trucks and giant worthless SUV'* they sell. The 5w20 increases their CAFE by like .1 or .2 MPG. Honda is just doing it because they are a very enviromental friendly company.
Azwed is offline   Reply With Quote
Old 05-29-2003, 12:56 AM   #5
Senior Member
Posts like a Turbo
 
Join Date: Jul 2002
Posts: 417
Thanks: 0
Thanked 0 Times in 0 Posts
Azwed is on a distinguished road
Default

Quote:
Originally Posted by jr's3800
Thanks Azwed.... Love new info...

I wonder how well that 5w-20 would protect a ford engine in the blazing heat of arizona, like the grand canyon in the middle of July in temps as high as 115 F driving up plenty of hills in a ford expedition over working that 4.6 V8... I haven't heard of many probs with the 5w-20 oil in these SUV'* but maybe you know something...

Well since it is a ford it will only last on average half as long as any other motor ever built. Thats just a given and no way around it.

The new 5w20 is supposed to be a highly refined petroleum based oil simlar to the Castro Syntec brand. I forget the techincal chemical name of the oil but I think the trade name is a type III synethetic oil which is not a real synthetic just a motor oil using a highly refined petroleum base stock with some synthetic properties. Mobil 1 tool them to court over this but ended up losing.

The regular 5w20 would probably do ok but real full synthetic 5w20 would be better. I used the Amsoil 5w20 full synthetic in my bonne for about 4 months last year and didn't notice much difference. I had about the same oil consumption and about the same, possibly slightly worse, mpg. I think my motor is just to old and does not have the tight tollerances to take advantage of the thinner oil.
Azwed is offline   Reply With Quote
Old 05-29-2003, 03:21 PM   #6
Senior Member
True Car Nut
Thread Starter
 
Join Date: Oct 2002
Location: Genoa, Illinois
Posts: 4,013
Thanks: 0
Thanked 0 Times in 0 Posts
Allmachtige is on a distinguished road
Default

A great many I talk to said it was a good choice to go with 20-50 for the summer. Yet again these were all older people who have drag raced since the 70'*. I'll do some more research, but I would think more pressure would be helpful (or at least protecting) for when I make nitrous passes. But, maybe their thoughts are rubbing off on me...AHH! THEY ARE MAKING ME TURN INTO AN OLD BITTER MAN! *runs away screaming*
Allmachtige is offline   Reply With Quote
Old 05-30-2003, 12:58 AM   #7
Senior Member
Posts like a Turbo
 
Join Date: Jul 2002
Posts: 417
Thanks: 0
Thanked 0 Times in 0 Posts
Azwed is on a distinguished road
Default

Quote:
Originally Posted by Allmachtige
A great many I talk to said it was a good choice to go with 20-50 for the summer. Yet again these were all older people who have drag raced since the 70'*. I'll do some more research, but I would think more pressure would be helpful (or at least protecting) for when I make nitrous passes. But, maybe their thoughts are rubbing off on me...AHH! THEY ARE MAKING ME TURN INTO AN OLD BITTER MAN! *runs away screaming*

Ackk quick go play video games or something you are infected with old persons disorder.

See that keyword up their yes that evil word "the 70'*" well motors have changed a whole lot since then and so has oil. The original reason thicker viscosity oils were used in HiPo engines was to increase film and shear strength. Think of film strength like the water tension on the top of a glass of water. The stronger the water tension in the more weight it can support before an object is partialy submerged in the water.

A high film strength in oil stops metal to metal contact. High shear strength has a similar effect.

Old people still think the only way to get this protection is with thick oils because thats the way things were 20-30 years ago. Modern oils are much better then oil from 20 years ago and don't need to be so thick to provide protection. Synthetics provide such high film strength that there is esentialy no wear in a motor. I have seen camshafts come out of small block chevys with 100k, 200k and even 250k always using synthetic and the cams looked almost brand new.

The old rule of thumb is about 10 psi of oil presure per 1000 rpms. You really don't want to see more then about 60 psi if pressure ever on most street motors. Anymore then that and you are going to start seeing increased blow by and oil consumption from having to high of an oil pressure. Oil pressure is like almost everything else in the world you can have too much of it. You are also putting more strain on oil pump since it is having to turn through that thick oil.
Azwed is offline   Reply With Quote
Old 05-30-2003, 04:17 PM   #8
Senior Member
True Car Nut
Thread Starter
 
Join Date: Oct 2002
Location: Genoa, Illinois
Posts: 4,013
Thanks: 0
Thanked 0 Times in 0 Posts
Allmachtige is on a distinguished road
Default

Well ****.

I'll just have to go get some Valviline Synthetic 10w-30 tonight.
Thanks for the info Azwed, and I'll be sure to play some video games tonight.
Allmachtige is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
SERIES 1 L27/L67 COMPARISON willwren Performance, Brainstorming & Tuning 52 01-16-2005 09:12 PM
Quick tire/rim size comparison chart for the Bonne DJ SHO General GM Chat 17 11-15-2004 09:22 PM
96 SSEi vs 96 Olds Aurora Comparison Jim W General GM Chat 282 09-18-2004 12:25 AM
A year in comparison...plus some more SSEimatt93 Your Ride: GM Pictures & Videos 5 05-17-2004 09:55 PM
exhaust chart. Comparison Drifter420 Performance, Brainstorming & Tuning 2 05-06-2004 02:28 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 03:01 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.