Oil choices for 240Z race car

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We run 20w50 VR1 in dads 240z. (They also make it in 10w30 and straight weights too IIRC.) Not a race car by any means, but it does have the higher compression head. E31 I think. I can't remember.
 
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Originally Posted by michaelsvintage
Originally Posted by Jackson_Slugger
The also make a 0W-30 and a 0W-50 specifically for racing: https://mobiloil.com/en/motor-oils/mobil-1/mobil-1-racing-oil
Yes, thanks! I've talked to a couple Z racers and they said the Mobil 1 oils get very "watery" when they get hot. As these engines don't run a ton of oil pressure, I'd rather not have to worry about that possibility.
All oil gets watery when hot. It's not pancake syrup when it's 200+*F.
 

michaelsvintage

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Originally Posted by dlundblad
Originally Posted by michaelsvintage
Originally Posted by Jackson_Slugger
The also make a 0W-30 and a 0W-50 specifically for racing: https://mobiloil.com/en/motor-oils/mobil-1/mobil-1-racing-oil
Yes, thanks! I've talked to a couple Z racers and they said the Mobil 1 oils get very "watery" when they get hot. As these engines don't run a ton of oil pressure, I'd rather not have to worry about that possibility.
All oil gets watery when hot. It's not pancake syrup when it's 200+*F.
Yes, I mean relative to other oils. One racer described a 20psi loss in running oil pressure, compared to 2psi under similar conditions with the Amsoil mentioned in the OP. VR1 is an option, but honestly I'm a little guy shy about it because the previous owners were running it and I discovered a wiped cam. Could obviously be a coincidence, but it could also be indicative of something.
 
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Originally Posted by michaelsvintage
Originally Posted by dlundblad
All oil gets watery when hot. It's not pancake syrup when it's 200+*F.
Yes, I mean relative to other oils. One racer described a 20psi loss in running oil pressure, compared to 2psi under similar conditions with the Amsoil mentioned in the OP. VR1 is an option, but honestly I'm a little guy shy about it because the previous owners were running it and I discovered a wiped cam. Could obviously be a coincidence, but it could also be indicative of something.
If that is the case then the grade ExxonMobil prints on the containers is incorrect. Either it meets the viscosity range appropriate for the grade or it doesn't. It sounds like a lot of racers try and use the "eye viscometer" and are failing, just like everyone else who attempts to do so. And that wiped cam, how did you determine it was due to the oil? Not due to poor design or material failure?
 

michaelsvintage

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Originally Posted by kschachn
Originally Posted by michaelsvintage
Originally Posted by dlundblad
All oil gets watery when hot. It's not pancake syrup when it's 200+*F.
Yes, I mean relative to other oils. One racer described a 20psi loss in running oil pressure, compared to 2psi under similar conditions with the Amsoil mentioned in the OP. VR1 is an option, but honestly I'm a little guy shy about it because the previous owners were running it and I discovered a wiped cam. Could obviously be a coincidence, but it could also be indicative of something.
If that is the case then the grade ExxonMobil prints on the containers is incorrect. Either it meets the viscosity range appropriate for the grade or it doesn't. It sounds like a lot of racers try and use the "eye viscometer" and are failing, just like everyone else who attempts to do so. And that wiped cam, how did you determine it was due to the oil? Not due to poor design or material failure?
I'm just reporting what I've been told, but since there are multiple sufficient options I see no reason to take the chance. The cam failure may have been a material issue, but it was an Isky cam with one of their "normal" grinds so I'm not sure I'd say the design was to blame. There was a lot more lift and therefore spring pressure with that cam as well, but again if I have multiple good options and one may have been an issue, I see no real reason to spend my time and potentially my parts to find out for sure. This car doesn't get the same time as my customer cars do (cobbler's shoes situation) so I need to be as efficient as I can with the time I spend on it.
 
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An L series motor as assembled by Nissan is an EXTREMELY durable engine. Years ago it wasn't uncommon to utilize a high mileage (150k or more) motor, replace the timing chain, do a valve job and put the motor back into service under RACING conditions. Rebuilds with aftermarket parts ruin these motors. If you're experiencing camshaft and/or valvetrain wear (or bottom end issues), it's probably not the choice of oil. It's the aftermarket junk parts that were used for the "rebuild" process.
 

michaelsvintage

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Originally Posted by Powerglide
An L series motor as assembled by Nissan is an EXTREMELY durable engine. Years ago it wasn't uncommon to utilize a high mileage (150k or more) motor, replace the timing chain, do a valve job and put the motor back into service under RACING conditions. Rebuilds with aftermarket parts ruin these motors. If you're experiencing camshaft and/or valvetrain wear (or bottom end issues), it's probably not the choice of oil. It's the aftermarket junk parts that were used for the "rebuild" process.
That's very possible. Unfortunately, I've learned time and again since I bought this car that the previous owners didn't do things the right way. I'm continuing to tidy up the fallout.
Originally Posted by aquariuscsm
My 280Z always got Castrol GTX 10W30. But if I was building a high performance race car,I'd probably use Redline.
Alright, thanks!
Originally Posted by Powerglide
An L24, 26 or 28 will run 300k+ miles on the appropriate viscosity oil of any API certified brand of your choice.
I'd have to imagine things would be a little different with a race engine though, no?
 
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I'm having a hard time believing there'd be that much in oil pressure difference between 2 brands assuming they used the same viscosity both times. No way. An owners manual says basically 5w30 to 20w50 is safe to use depending on temperature. Just throwing this out there, I am not sure what it being a race car has to do with oil being too thick. Tracked applications require a thicker oil if I am not mistaken. You've gotten plenty of good and correct advice from everyone who's commented.
 

michaelsvintage

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Originally Posted by dlundblad
I'm having a hard time believing there'd be that much in oil pressure difference between 2 brands assuming they used the same viscosity both times. No way. An owners manual says basically 5w30 to 20w50 is safe to use depending on temperature. Just throwing this out there, I am not sure what it being a race car has to do with oil being too thick. Tracked applications require a thicker oil if I am not mistaken. You've gotten plenty of good and correct advice from everyone who's commented.
I agree about the oil pressure to a point, but I will also say we had more than one oil pressure-related failure in our customer engines when using Mobil 1 and they've disappeared since switching away from it. I see no reason to challenge the guy on it since I'm not being forced to use Mobil 1. Having used the 20W-50 in the car, the oil pressure was quite a bit higher than what other Z racers have reported aiming for in their cars. That may not necessarily be detrimental to the engine, but thicker-than-necessary oil will rob some power and since my engine isn't a monster I'm happy to find gains where I can.
 
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