what is the best oil for FI apps, honest opinions

[Whipped416]

hey andy why 15w50? i am running amsoil 5w30 ...thanks for your input and knowledge

[JusticePete]

One of the benefits of having a good relationship with GM is we can ask questions like this and get answers from people that have direct knowledge on the subject. I asked the question posed by the OP and others in this thread.

At GM we are responsible for engine warranties and durability. We continuously test engine oils to see if there is any oil available that would improve reliability and reduce warranty. If there was a better oil than Mobil 1 GM would already be using it.

I may not have typed the exact words of our conversation, but the meaning is exactly what was discussed. The engineer this came from has been racing GM cars for many years. He owns them. He uses Mobil 1.

[boostedyards86]

Originally Posted by ADM PERFORMANCE

GM Uses 5-30 in almost all their engines.

Every engine that has had my hands on it leaves running 15w-50 in it,I started this 9 years ago when John Lingenfelter told me that is what they
put in all their builds.

Andy is this true even for stock internals or for motors that you built. like say supercharged with an unopened motor...?

[ADM PERFORMANCE]

Originally Posted by boostedyards86

Andy is this true even for stock internals or for motors that you built. like say supercharged with an unopened motor...?

Yes even stock internals

[600hp-lpe]

Originally Posted by boostedyards86

Andy is this true even for stock internals or for motors that you built. like say supercharged with an unopened motor...?

Yes... if it's supercharged (modified or with a stock block), you want the added viscosity a 15-50 oil has - this helps extend bearing life.

[boostedyards86]

good to know

[ipimpthisc]

Originally Posted by JusticePete

One of the benefits of having a good relationship with GM is we can ask questions like this and get answers from people that have direct knowledge on the subject. I asked the question posed by the OP and others in this thread.

At GM we are responsible for engine warranties and durability. We continuously test engine oils to see if there is any oil available that would improve reliability and reduce warranty. If there was a better oil than Mobil 1 GM would already be using it.

I may not have typed the exact words of our conversation, but the meaning is exactly what was discussed. The engineer this came from has been racing GM cars for many years. He owns them. He uses Mobil 1.

excellent point...but i can also point out that companies love to make money..now if u can make a motor to just past warranty, and then crack,,,and then charge for parts and rebuilds..the bottom line rules. And we all know that the love money is the root to all evil. Not like companies are so loyal and caring that they always help the lil guy. matter of fact my stock oil pump siezed...I hear GM knows about this...yet what have they done to inform any ls3 owner "nothing"...but Pete I respect u, let me say. I see u do lots of R&D and so on...just my .02 my respected brother

[JusticePete]

Originally Posted by ipimpthisc

excellent point...but i can also point out that companies love to make money..now if u can make a motor to just past warranty, and then crack,,,and then charge for parts and rebuilds..the bottom line rules. And we all know that the love money is the root to all evil. Not like companies are so loyal and caring that they always help the lil guy. matter of fact my stock oil pump siezed...I hear GM knows about this...yet what have they done to inform any ls3 owner "nothing"...but Pete I respect u, let me say. I see u do lots of R&D and so on...just my .02 my respected brother

Nothing but here.

The gentleman I was speaking with was not giving me the GM line. We were track side talking road course and racing. This is the same guy that has been involved in oil / wear tests. The same guy that puts Mobil 1 in his personal race car. This same guy has brand-x brake pad stickers on his race car, but his pads are Cobalt Friction. Why, he like the guy at brand-x, but also wants to win.

GM isn't perfect as you noted in your post. I am hoping they will get closer to perfect as many of the younger engineers I know move up the ladder.

[Camaro21]

Originally Posted by LittleMT

A little birdie once told me "A little something we recommend- always
Run 15w 50 mobil 1"

I think i'll listen to this guy, he knows a thing or two...

The same little birdie told me that too !! That's what I use. I have over 67,000 HARD Miles on my Supercharged Camaro with no issues (except for the stock axle I broke a few weeks ago). I do ALOT of drag racing too !!

[ipimpthisc]

Originally Posted by JusticePete

Nothing but here.

The gentleman I was speaking with was not giving me the GM line. We were track side talking road course and racing. This is the same guy that has been involved in oil / wear tests. The same guy that puts Mobil 1 in his personal race car. This same guy has brand-x brake pad stickers on his race car, but his pads are Cobalt Friction. Why, he like the guy at brand-x, but also wants to win.

GM isn't perfect as you noted in your post. I am hoping they will get closer to perfect as many of the younger engineers I know move up the ladder.

ok Pete...this does add a whole other level...thank you ...and tell him I thank him as well

[etdrag]

You can't go wrong with mobile 1 also Amsoil is a great oil too, that is all use unless it is breaking in then i will use something else depending on the motor and bearings.

[pdesanctis]

Originally Posted by old motorhead

The only time I go with a heavier oil is when the motor has big miles. Several or my GM trucks are now run on 15w40 oil after 200K miles. No way would I run a heavier oil on a newer motor. Even in our lovely 100+ degree heat. My daily driver GMC is supercharged with a forged motor. The guy that did the machine work and set up the clearances recommended 15w50. Guess what I run in that one. The well established synthetics are all pretty good in my book. I'd pick one that's readily available and you're comfortable with and run it at the recommended weight.

I have used 15w40 in a new/stock LS3. No harm done except the engine was very sluggish.

For all you FI guys. If your engine runs very hot 250+ then you need a heavier weight oil with a good amount zddp.

The reason the ZR1/LS9 uses 5w30 is because it has a massive oil cooler.

If you want to run a lighter weight oil like 5w30/10w30 then put in a big oil cooler to keep engine temps/ oil temps down.

The hotter the engine the thicker the oil you need to run. Simple as that.

Read up on bobistheoilguy.com

Enjoy!

As soon as I install Twin Turbos I will most likely be running Mobil 1 15w50.

Keep in mind, not all M1 oils are the same. Their basic 5w30 is an average oil. However Mobil 1's 15w50 and 0w40 are their flagship oils. They are two of the best oils out there. M1 15w50 is a great choice for FI, high temp cars.

[pdesanctis]

http://lib.store.yahoo.net/lib/yhst-...cebrochure.pdf