HP loss with heavier oil?
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Staging Lane
Joined: Dec 2002
Posts: 98
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From: Etters, PA
HP loss with heavier oil? This is logically supposed to be true. Last night a pal dynoed 3 pulls with 10-30 Mobil 1 and had a best of 341 rwhp. This oil had about 1700 miles on it. We changed over to Mobil 1 0-40 and pulled 343. If no power was lost, the extra film strength should be a no brainer.
Re: HP loss with heavier oil? I would like to see Patman's comments on this as he really has a good deal of info on oil and test results.
IMO 2rwhp isn't worth pulling 0w-40 in the car.
Technically, if the car is still in warranty the 0w-40 could void the warranty on the engine if an oil related failure occured. Owners manual says 5w-30 or 10w-30 and I'd stick with that unless it's a custom short block and the engine builder said otherwise.
<img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
IMO 2rwhp isn't worth pulling 0w-40 in the car.
Technically, if the car is still in warranty the 0w-40 could void the warranty on the engine if an oil related failure occured. Owners manual says 5w-30 or 10w-30 and I'd stick with that unless it's a custom short block and the engine builder said otherwise.
<img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
Re: HP loss with heavier oil? BTW the way good testing info.
If 10w-30 was two hp less than 0w-40, 5w-30 might be right in the middle for power. The 5w-30 might be worth 1rwhp over 10w-30 and would keep the warranty intact. Also dyno's runs can realistically vary by 1 percent.
If 10w-30 was two hp less than 0w-40, 5w-30 might be right in the middle for power. The 5w-30 might be worth 1rwhp over 10w-30 and would keep the warranty intact. Also dyno's runs can realistically vary by 1 percent.
TECH Junkie
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Re: HP loss with heavier oil? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 99 Black Bird T/A:
<strong>BTW the way good testing info.
If 10w-30 was two hp less than 0w-40, 5w-30 might be right in the middle for power. The 5w-30 might be worth 1rwhp over 10w-30 and would keep the warranty intact. Also dyno's runs can realistically vary by 1 percent.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I don't think this test shows anything. I bet if he would have put 10w-30 back in the car again he would have picked up 2rwhp just from changing out old oil!
The only way to be sure is to put new 10w30 and then new 0w40 and compare the results on 2 new oils, not and old and new.
<strong>BTW the way good testing info.
If 10w-30 was two hp less than 0w-40, 5w-30 might be right in the middle for power. The 5w-30 might be worth 1rwhp over 10w-30 and would keep the warranty intact. Also dyno's runs can realistically vary by 1 percent.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I don't think this test shows anything. I bet if he would have put 10w-30 back in the car again he would have picked up 2rwhp just from changing out old oil!
The only way to be sure is to put new 10w30 and then new 0w40 and compare the results on 2 new oils, not and old and new.
10 Second Club
Joined: Nov 2002
Posts: 1,471
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From: Berkeley, California
Re: HP loss with heavier oil? I am just adding a simple reminder to be sure that you are not being led astray by the intuitive idea that thicker oil is somehow always stronger. Higher viscosity oil does not necessarily provide better protection nor is "higher film strength" an important consideration. The main value of higher viscosity oil is to reduce oil consumption which it does by reducing flow past piston rings and down valve guides. The worst lubrication failure is absence of oil rather than some sort of oil breakdown. Lower viscosity oil helps ensure that oil is present where it is needed. When it comes to lubrication, we shouldn't stray far from GM's recommendations.
-Gary
<small>[ December 01, 2002, 01:15 PM: Message edited by: Gary Z ]</small>
-Gary
<small>[ December 01, 2002, 01:15 PM: Message edited by: Gary Z ]</small>
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From: Plainville,MA
Re: HP loss with heavier oil? Mobil 1 15-50 spoken here ! <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
I bought this car brand new and ran 5-30 dino until 20,000 miles when at that time I installed a TNT F-1 wet kit !
With the 5-30 dino non n2o I would burn a quart every 1000 miles to the mile ! <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
Now I add the n20 and my reasoning said thicker oil would be better protection against the n20 abuse and I do mean abuse !
I now add "NO" oil between 3000 mile changes ! <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
As of now the car has been thru 21 10 pound Purple bottles, <img border="0" title="" alt="[Embarrassed]" src="gr_emb.gif" /> and now has 27,500 miles and has made 380+ 1320 passes and 150+ dyno pulls all the way to 6600 rpm !
I would say all in all the 15-50 was good cheap insurance for motor longevity !
I bought this car brand new and ran 5-30 dino until 20,000 miles when at that time I installed a TNT F-1 wet kit !
With the 5-30 dino non n2o I would burn a quart every 1000 miles to the mile ! <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
Now I add the n20 and my reasoning said thicker oil would be better protection against the n20 abuse and I do mean abuse !
I now add "NO" oil between 3000 mile changes ! <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
As of now the car has been thru 21 10 pound Purple bottles, <img border="0" title="" alt="[Embarrassed]" src="gr_emb.gif" /> and now has 27,500 miles and has made 380+ 1320 passes and 150+ dyno pulls all the way to 6600 rpm !
I would say all in all the 15-50 was good cheap insurance for motor longevity !
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Thread Starter
Staging Lane
Joined: Dec 2002
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From: Etters, PA
Re: HP loss with heavier oil? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Gary Z:
<strong>I am just adding a simple reminder to be sure that you are not being led astray by the intuitive idea that thicker oil is somehow always stronger. Higher viscosity oil does not necessarily provide better protection nor is "higher film strength" an important consideration. The main value of higher viscosity oil is to reduce oil consumption which it does by reducing flow past piston rings and down valve guides. The worst lubrication failure is absence of oil rather than some sort of oil breakdown. Lower viscosity oil helps ensure that oil is present where it is needed. When it comes to lubrication, we shouldn't stray far from GM's recommendations.
-Gary</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
<strong>I am just adding a simple reminder to be sure that you are not being led astray by the intuitive idea that thicker oil is somehow always stronger. Higher viscosity oil does not necessarily provide better protection nor is "higher film strength" an important consideration. The main value of higher viscosity oil is to reduce oil consumption which it does by reducing flow past piston rings and down valve guides. The worst lubrication failure is absence of oil rather than some sort of oil breakdown. Lower viscosity oil helps ensure that oil is present where it is needed. When it comes to lubrication, we shouldn't stray far from GM's recommendations.
-Gary</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
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Staging Lane
Joined: Dec 2002
Posts: 98
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From: Etters, PA
Re: HP loss with heavier oil? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Gary Z:
<strong>I am just adding a simple reminder to be sure that you are not being led astray by the intuitive idea that thicker oil is somehow always stronger. Higher viscosity oil does not necessarily provide better protection nor is "higher film strength" an important consideration. The main value of higher viscosity oil is to reduce oil consumption which it does by reducing flow past piston rings and down valve guides. The worst lubrication failure is absence of oil rather than some sort of oil breakdown. Lower viscosity oil helps ensure that oil is present where it is needed. When it comes to lubrication, we shouldn't stray far from GM's recommendations.
-Gary</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Keep in mind, GM's recommendation is for a motor with a stock lift cam, putting out stock power, reving to a stock rev limiter, that need to get maximum gas milage.
<strong>I am just adding a simple reminder to be sure that you are not being led astray by the intuitive idea that thicker oil is somehow always stronger. Higher viscosity oil does not necessarily provide better protection nor is "higher film strength" an important consideration. The main value of higher viscosity oil is to reduce oil consumption which it does by reducing flow past piston rings and down valve guides. The worst lubrication failure is absence of oil rather than some sort of oil breakdown. Lower viscosity oil helps ensure that oil is present where it is needed. When it comes to lubrication, we shouldn't stray far from GM's recommendations.
-Gary</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Keep in mind, GM's recommendation is for a motor with a stock lift cam, putting out stock power, reving to a stock rev limiter, that need to get maximum gas milage.
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From: Centrifugal City
Re: HP loss with heavier oil? I just changed from Redline 10W30 to Redline 10W40. The car does feel a touch down from before. SOTP is hard to measure tho. But does feel a little doggier. Getting ready for the SC. Figured with the heat and the SC load I'd go up a weight.
Thread Starter
Staging Lane
Joined: Dec 2002
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From: Etters, PA
Re: HP loss with heavier oil? The gain was not my point. A heavier oil, that offers better bearing protection, should cost a few horses. If you can get better protection with no differece, why not use it. Ask anyone who has torn down LS1 cars. The bearings usually don't look very good. Mikey will support me on this.
Re: HP loss with heavier oil? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by SShady:
<strong>The gain was not my point. A heavier oil, that offers better bearing protection, should cost a few horses. If you can get better protection with no differece, why not use it. Ask anyone who has torn down LS1 cars. The bearings usually don't look very good. Mikey will support me on this.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">SShady, I agree with you 110%. About 95% of the internet doesn't have a clue how sensitive the stock LS1 bearings are, so they run 5w30(thinner than ****) and wonder why their bearings are toast when they do a tear down.
I personally recommend running 10w30 for LS1's in the 0-45K range, and from then on at least 10w40. I have a few buddy's running 15w50 with good results and zero noticable power loss on the dyno. As you said, if it costs me 5 hp to keep my bearings in better shape, so be it....
Josh
<strong>The gain was not my point. A heavier oil, that offers better bearing protection, should cost a few horses. If you can get better protection with no differece, why not use it. Ask anyone who has torn down LS1 cars. The bearings usually don't look very good. Mikey will support me on this.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">SShady, I agree with you 110%. About 95% of the internet doesn't have a clue how sensitive the stock LS1 bearings are, so they run 5w30(thinner than ****) and wonder why their bearings are toast when they do a tear down.
I personally recommend running 10w30 for LS1's in the 0-45K range, and from then on at least 10w40. I have a few buddy's running 15w50 with good results and zero noticable power loss on the dyno. As you said, if it costs me 5 hp to keep my bearings in better shape, so be it....
Josh
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From: Mississauga, Ontario
Re: HP loss with heavier oil? Gary is right, a lot of people immediately think that a thicker oil always equals better engine protection but it's not always the case. If the oil pump can't pump it fast enough, you could starve the engine for lubrication. So putting 20w50 in a bone stock LS1 is a nono. However with a built up LS1 with a better oil pump, it would be possible. But I still believe that a 0w40, 10w40 or 15w40 is about as thick as you need. It is hard for a dyno to measure a 2-3hp change, but with the thicker stuff you will typically lose a bit of power, simply due to the engine having to work harder with this thicker viscosity. Keep in mind if you go too thick, this higher load equals hotter oil temps too.
I'm surprised that more of you aren't into doing oil analysis, because this would really help you choose an oil. If you run a couple of intervals with 10w30, then try a couple of intervals with a 40wt oil, you'll be able to see if your wear metals go up or down. That's truly the best way to see if what you've done is right.
I will say this, Mobil 1's 0w40 is an excellent oil, it is very shear stable.
I'm surprised that more of you aren't into doing oil analysis, because this would really help you choose an oil. If you run a couple of intervals with 10w30, then try a couple of intervals with a 40wt oil, you'll be able to see if your wear metals go up or down. That's truly the best way to see if what you've done is right.
I will say this, Mobil 1's 0w40 is an excellent oil, it is very shear stable.
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From: SC
Re: HP loss with heavier oil? I switched to 10w30, and noticed that the car burns considerably less oil from 5-30 (both Mobil-1). Before every time I would go to the track and run I would be at least a quart down afterwards. Last few times on 10-30 I have not had to add any oil. Car feels the same with either oil, but I have found my SOTP to only be sensative to about 10rwhp.
