Turbo VQ35 & Heat

Status
Not open for further replies.
C

Cerberus350z

Joined
Jan 4, 2009
Messages
6
Location
Maine
I apologize for making this thread, I searched and poked around a few threads, but the search feature here seems kinda sketchy so here I am.

Over the winter I had a single turbo installed, and now I am up for my second oil change in the heat of summer I have been doing some research.

I do not have a oil cooler installed currently, and I have been seeing oil temps in the 220F range, and up to 240F with sustained revs. I have been running Pennzoil 5w-30 ultra before and after the turbo install. I just called their tech line and they claim they can hold temps up to 220C. What are your thoughts on this?

My question is should I just keep on doing what I am doing, or should I go up to a 40 weight because of the higher temps and abuse it may see from the turbo and my right foot?
 
Yes. While that's a good oil that I have some of and plan to run during the winter, you'll be better off going heavier w/ some added ZDDP IMNSHO. Try Rotella T6.
 
Originally Posted By: Cerberus350z
should I go up to a 40 weight because of the higher temps and abuse it may see from the turbo and my right foot?


Yes.

The last 2 car brands I owned (Subary and Toyota) specifically say to go up in viscosity with high load/high speed/high temps service.
 
You do have an oil pressure gauge?
240F is not all that hot and a 5W-30 (PU is heavier than PP) may still provide sufficient operational viscosity. Your OP will tell you. Don't know what the OP spec' is for your engine but I would think if you're still maintaining 65 psi at elevated rev's with oil temp's peaking at 240F there's no reason to run anything heavier.
 
I'd rather run a 40-weight "just in case" rather than running a 30-weight just because the oil pressure gauge says you can in this case. Does your car have a larger oil pan, or the stock pan with the same small sump?

Rotella T6 is a good bargain, but if you don't feel comfortable running that there's always Mobil 0w-40. Redline's 5w-30 is also an excellent choice for your needs, though it is rather expensive if you can't find it locally.
 
I do have a a oil pressure guage and the PSI is in the high 50s or 60s at high RPMS.

I also have a oil pan spacer that adds an additional quart to the capacity of the oil pan, bringing me to approximately 6 quarts.
 
Originally Posted By: Cerberus350z

I also have a oil pan spacer that adds an additional quart to the capacity of the oil pan, bringing me to approximately 6 quarts.


Funny how you didn't volunter that info. That is effectively your oil cooler, but I would still use 40 to play it safe.
 
Originally Posted By: Cerberus350z
I do have a a oil pressure guage and the PSI is in the high 50s or 60s at high RPMS.

I also have a oil pan spacer that adds an additional quart to the capacity of the oil pan, bringing me to approximately 6 quarts.

The oil pan spacer allowing an additional quart is a good idea and does lower oil temp's especially for street use.
Since you've got an OP gauge see if you can get the OP spec's from the factory manual. There are usually two provided, one at idle and another at a specified higher rpm. It doesn't mean you can't safely run OP somewhat lower when the oil gets hot but it's a good reference point to know where your at in terms of optimum operational viscosity.
Also, keep in mind when fine tuning the oil viscosity to your own application that OP correlates with the HTHSV rating of an oil. If you want slightly higher OP then you'll want an oil with a slightly higher HTHSV rating. Best results are made by taking small steps, afterall you're oil temp's and therefore the oil's viscosity is 100% controlled by your right foot and how long you keep the engine on boost.
 
Ran Mobil 0w40 in my turbo Audi 1.8T which consistently indicated 220-230 degrees Fahrenheit during summer driving in Texas.
 
Originally Posted By: friendly_jacek

Funny how you didn't volunter that info. That is effectively your oil cooler, but I would still use 40 to play it safe.


What is funny, is how you have offered very little information aside from generalizations, and now are insinuating that I purposely left this information out to trick you into giving me an incorrect answer.
 
Last edited:
Originally Posted By: CATERHAM
Originally Posted By: Cerberus350z
I do have a a oil pressure guage and the PSI is in the high 50s or 60s at high RPMS.

I also have a oil pan spacer that adds an additional quart to the capacity of the oil pan, bringing me to approximately 6 quarts.

The oil pan spacer allowing an additional quart is a good idea and does lower oil temp's especially for street use.
Since you've got an OP gauge see if you can get the OP spec's from the factory manual. There are usually two provided, one at idle and another at a specified higher rpm. It doesn't mean you can't safely run OP somewhat lower when the oil gets hot but it's a good reference point to know where your at in terms of optimum operational viscosity.
Also, keep in mind when fine tuning the oil viscosity to your own application that OP correlates with the HTHSV rating of an oil. If you want slightly higher OP then you'll want an oil with a slightly higher HTHSV rating. Best results are made by taking small steps, afterall you're oil temp's and therefore the oil's viscosity is 100% controlled by your right foot and how long you keep the engine on boost.


Thank you

I'll keep an eye on it. So far the readings have not been far off from the OEM gauge. I will also give the manual a glance, I didn't think they would get so technical in it.
 
Originally Posted By: CATERHAM
Originally Posted By: mechtech2
At 240 deg F, you should go to the 40.

What "40"? And since you don't give your reason, not very helpful.


I used the definite article 'the' to refer to the 40 of the indefinite article 'a' the the OP used.
Whether I give a good enough reason for you is not important to me.
My advice is good, safe, and sane.
Need a good one? M1 0-40 is great with street turbos.
 
Originally Posted By: mechtech2
Originally Posted By: CATERHAM
Originally Posted By: mechtech2

.
Whether I give a good enough reason for you is not important to me.
My advice is good, safe, and sane.
Need a good one? M1 0-40 is great with street turbos.

Since this is not your thread what's important to you is of no concern. I'm not looking for advice but the OP was.
A final specific recommendation and your reason has some value.
Yes, M1 0W-40 is an excellent 40wt choice if the OP actually needs an oil that heavy. I'm saying he likely doesn't with oil temp's that only occationally may hit 240F.

For example, the twin turbo in the BMW 3351 and 135i that a number of members have, routinely will see oil temp's in the 260F range and BMW still spec's their rather light (in service) 5W-30 for it.
 
Originally Posted By: Cerberus350z
I do have a a oil pressure guage and the PSI is in the high 50s or 60s at high RPMS.

I also have a oil pan spacer that adds an additional quart to the capacity of the oil pan, bringing me to approximately 6 quarts.


The oil pan spacer is a good idea, but did the kit also include a way to lower the oil pickup to keep it the same distance off the bottom of the pan? The extra oil in the pan will help prolong oil life by reducing the recirculation rate, but if the pickup is further off the floor of the pan, it will be uncovered sooner if you are subjecting the car to high lateral G's.
 
Originally Posted By: A_Harman

The oil pan spacer is a good idea, but did the kit also include a way to lower the oil pickup to keep it the same distance off the bottom of the pan? The extra oil in the pan will help prolong oil life by reducing the recirculation rate, but if the pickup is further off the floor of the pan, it will be uncovered sooner if you are subjecting the car to high lateral G's.


Yes it did, there is a spacer that lowered the pick up the same thickness of the spacer.
 
Originally Posted By: Cerberus350z
Originally Posted By: friendly_jacek

Funny how you didn't volunter that info. That is effectively your oil cooler, but I would still use 40 to play it safe.


What is funny, is how you have offered very little information aside from generalizations, and now are insinuating that I purposely left this information out to trick you into giving me an incorrect answer.


Now I'm sorry I responded to your post. Whatever.
 
Quote:
do have a a oil pressure guage and the PSI is in the high 50s or 60s at high RPMS.


So it has high 50's to low 60's and sees 240f temp. If these temps go any higher its probably going to be lower.

Controlling viscosity and oil temp with your right foot is one of the most ridiculous things i ever heard.
Think about it. You just get clipping along good under boost and see the temp go up and the pressure drop so you need to back off it? Sorry but thats just horse manure.

Turbo chargers that run for more than a few minutes producing full boost are hard on the oil.

I have one of these engines (not boosted) in MA and it runs smoother and much quieter on 0w40 than anything else including Nissan recommended ester stuff.
I have had (still do) a lot of turbo applications and every one of them needed heavier oil.

Do yourself a big favor and go to Mobil 1 UK and see what oil they recommend for use in the UK.
I say UK because if i say Germany the thin oil brigade cries foul and comes up with "they have the Autobahn".

The UK has 70mph speed limits and is a similar climate to Maine.
Look up Nissan 3.5 in a Z car (same motor) 0w40 every year!
Before someone pipes up with "the bearings clearances are different" No they are not!

Mobil 1 0w40 is ideal for this application.

http://www.mobil.co.uk/UK-English-LCW/carengineoils_which-oil.aspx
 
Status
Not open for further replies.

Similar threads

Z
First turbo vehicle for me....oil thoughts?
2
Replies
26
Views
1K
Triple_Se7en
Camperguy
3.6 Pentastar viscosity done by clearance and temperature
2
Replies
32
Views
2K
kschachn
W
Mazda 2.5T Oil Selection
Replies
2
Views
449
drtyler
Ronin73
2023 Ford F150 3.5 EcoBoost Recommendation
Replies
17
Views
1K
Whimsey
B
Engine oil for Porsche 996 Turbo 0w40 or 5w50
Replies
8
Views
2K
bcnr33v
Back
Top