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20w-50 Oil

  • Thread starter Thread starter Optimus76
  • Start date Start date Aug 22, 2013
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Optimus76

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#1
  • Aug 22, 2013
  • #1
I have a motor that was set up for drag racing in my car. I don't think the previous owner put the right oil in the car. Only using synthetic. How many quarts should I be putting in? I think it's usually 5. But I just want to make sure first.
 

Noobz347

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#2
  • Aug 22, 2013
  • #2
Optimus76 said:
I have a motor that was set up for drag racing in my car. I don't think the previous owner put the right oil in the car. Only using synthetic. How many quarts should I be putting in? I think it's usually 5. But I just want to make sure first.
Click to expand...


Stock motor and oil pan? If it was setup for drag racing, it probably has an after market pan on it. My motor is setup with a Miloden 7 quart pan. It's pretty much street only.

So there's no good way to answer your question without know what all has been done to the car.
 

Optimus76

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#3
  • Aug 22, 2013
  • #3
I think it's got a street pan. Not sure what kind. But I figure I would put 5 quarts in. Start it for a second. Check the oil and add accordinly. I did get a bigger oil filter (K&N). So I'm thinking 5 1/2 quarts would do it.

My motor is pretty much the same as the one in this article in the below link.

http://www.musclemustangfastfords.c..._into_a_5_0_l_small_block_engine/viewall.html
 

Noobz347

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#4
  • Aug 22, 2013
  • #4
If it's got the original dipstick in it, just add oil until you hit the mark.
 

Optimus76

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#5
  • Aug 22, 2013
  • #5
Cool. That's what I was figuring. I just didn't know if the oil would expend alot when it get's warmed up. Resulting in way too much oil in there. Thanks for your help. I'll be getting this thing on the track next Friday hopefully. So I should have a video up soon.
 

MikeH686

Mine is only two inches though.
10 Year Member
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#6
  • Aug 22, 2013
  • #6
It wouldnt expand so much as thin out
 

MFE92

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#7
  • Aug 22, 2013
  • #7
Thousands and thousands of factory dipsticks were marked wrong, so you can't trust them without verifying them. Drain the oil, change the filter, put 4 quarts in it, start it, let it come up to pressure, then shut it off and let it sit for a few minutes. Check the level on the dipstick. No matter what the stick says, wherever the oil is now is your "low" level. Mark the stick with a new mark if you have to. Now add a quart and check it again. That's your "full" level. Mark it if you have to. If you think you have half a quart extra in your oversize filter, then adjust the low and full fills accordingly.

No, the oil level won't change measurably with heat.
 

Noobz347

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#8
  • Aug 22, 2013
  • #8
MFE92 said:
Thousands and thousands of factory dipsticks were marked wrong, so you can't trust them without verifying them. Drain the oil, change the filter, put 4 quarts in it, start it, let it come up to pressure, then shut it off and let it sit for a few minutes. Check the level on the dipstick. No matter what the stick says, wherever the oil is now is your "low" level. Mark the stick with a new mark if you have to. Now add a quart and check it again. That's your "full" level. Mark it if you have to. If you think you have half a quart extra in your oversize filter, then adjust the low and full fills accordingly.

No, the oil level won't change measurably with heat.
Click to expand...


Ummm.... Unless it's an after market oil pan.
 

84Ttop

They make new pistons every day, so why worry?
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#9
  • Aug 22, 2013
  • #9
Quietly spectating...
 

MFE92

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#10
  • Aug 22, 2013
  • #10
Noobz347 said:
Ummm.... Unless it's an after market oil pan.
Click to expand...

Yes, but he said he thinks the pan is stock. And if it's an aftermarket oil pan, he needs to know (or decide) if it's a simply a higher-capacity pan, or if it's intended to keep the oil below the level of the crank, or both.
 

Optimus76

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Aug 26, 2013
#11
  • Aug 26, 2013
  • #11
I'll start with 4 quarts and keep checking and adding every 1/2 quart after. It should be fine.

One a side not. I blew out one of my headers over the weekend. So I just ordered some Hedman Headers. They looked pretty nice for the price. $139.99 for the pair with the gasket kit from Summit. Lifetime Warrenty. Anyone have any problems with these?
 

Optimus76

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Aug 26, 2013
#12
  • Aug 26, 2013
  • #12
84Ttop said:
Quietly spectating...
Click to expand...

I think you were just waiting to see if I was going to blow my engine up. lol.
 

84Ttop

They make new pistons every day, so why worry?
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#13
  • Aug 26, 2013
  • #13
Optimus76 said:
I think you were just waiting to see if I was going to blow my engine up. lol.
Click to expand...
Never, it's just a touchy thing. Without seeing or knowing exactly what pan is on the motor I hesitate to make a recommendation based on purely on speculation. I would rather give no advice then bad advice! How did you make out with it by the way?
 

Optimus76

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Aug 26, 2013
#14
  • Aug 26, 2013
  • #14
I'm going to check it out with my neighbor. He builds cars and mud racers. When you buy a car you told a lot of things. So I'm not sure what to believe. But I was told I got this car for a steal at $3700.00. That's coming from a person that dislikes Mustangs. So we are going to be going threw this car. Finding fact from fiction. But Tuesday night we are going to be changing the oil. This car has been sitting for like 2 years. Engine they told me has about 3,000 miles on it. So we'll see.
 

Grabbin' Asphalt

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Aug 26, 2013
#15
  • Aug 26, 2013
  • #15
Many years ago I put 20w-50 full synthetic oil in and then my oil pump shaft broke. My buddy was driving my car when the oil pressure dropped.
I was riding shotgun and was freakin' to say the least. I was dead broke and we decided to keep the rpms real low and try and make it to his house 5-7 miles away. Lifters were tappin' when we pulled in the driveway, WHEW!!!
Guess the thickness etc helped it from draining down so fast. We were also on his country road with no shifting going on, no traffic, just a straight shot.
We stayed low on the rpms and was praying. Full synthetic believer after that night.
I recently had ask my friend how far he thought we
were from his house when that happened, he said "8 miles." ...it was far though.
In fact still on the very same motor right now 193,000+ miles
 
Last edited: Aug 26, 2013

madspeed

Colonel Mustard
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#16
  • Aug 26, 2013
  • #16
you had to say it....
 

mikestang63

SN Certified Technician
Aug 27, 2012
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#17
  • Aug 26, 2013
  • #17
Just wondering why 20W-50? That is thick as molasses and robs HP.
 

Grabbin' Asphalt

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#18
  • Aug 26, 2013
  • #18
mikestang63 said:
Just wondering why 20W-50? That is thick as molasses and robs HP.
Click to expand...

I live in Ga and it gets insane hot here and with traffic in my DD, just adds to the mayhem heat. Luckily now I don' t sit in traffic consistantly anymore with job changes. I don't look at oil the same now though, I think of it as cheap insurance.
 

mikestang63

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#19
  • Aug 26, 2013
  • #19
Grabbin' Asphalt said:
I live in Ga and it gets insane hot here and with traffic in my DD, just adds to the mayhem heat. Luckily now I don' t sit in traffic consistantly anymore with job changes. I don't look at oil the same now though, I think of it as cheap insurance.
Click to expand...

K. I'm in South Florida where is barely gets under 70 in the "winter", and I run 5w30 in all my cars with no issues.
 

FastDriver

I was uncomfortably high & wearing a helmet
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#20
  • Aug 26, 2013
  • #20
The 2nd number represents the viscosity of the oil at near operating temperature. So, a 20w-50 or a 0w-50 is still about a 50 viscosity oil at near engine temp. The first number gives you an idea of how quickly the viscosity will change due to change in temperature. In fact, it's quite likely that a 0W-50 would be thicker in winter weather than a 10W-30 at cranking temperatures, for example. The critically important part of thinner oils in winter has to do with how long it takes, or how difficult it is to get the oil circulating and to get the oil pressure to rise throughout the engine. It's just not as bad as it used to be.

Thus, how hot it gets in the summer really doesn't make a difference. More concerning is how cold it gets in the winter.
 
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