baezi z06

iTrader: (2)

Hi guys

i´m having difficult choosing the right engine oil for my motor

it´s a nitrous build a bit loose whith TSP ported LS6 oil pump 3k miles on the motor
street/strip car

i wante to get more oil pressure out of it and i need thicker oil

i have run 10-30 VR1 and went to 10-40 royal purple and i got avarage more oil pressure but i want more psi/ higher weight oil , i just installed vacuum pump to it so i wante more protection, i´m also installing a oil cooler later.

but the thing is i´m in Iceland and here is a bit colder then in the US for example and i worrie about cold starts

it´s 20-45F on winter time some times much colder (i´m not using the car then though)

and 45-60F spring and summer and up to 70-75F few days a year :woohoo:

so what are you guys using??

and what would you recomed for me to use threw the spring and summer time here in Iceland

i was looking at Joe gibbs of Motul 15w 50 is that too heavy for me, i´m


thanks
Baezi

shorty(98TA)

Thicker oil gives you higher pressures because the pump is trying to force the thicker oil threw vains and passage ways engineered for 5w30. You are actually most likely moving less volume of oil threw your motor. I run 5w30 synthetic with a K&N oil filter and even at 50 degrees outside I hold no less than 45 psi at idle and low RPMs with a TSP ported LS6 oil pump

soundengineer

iTrader: (16)

Ask your builder what weight to use..

I had my motor built for a lot of nitrous...
I was told 10w30 valvoline vr-1 non synthetic after I switched from the Joe gibbs break in oil.

My engine when hot, is 20-25 psi at idle, 40-45 at cruise, 50+ at wot.

Oil pressure will vary depending on how tight or how loose it was built and what weight of oil you use.

There is no magical # that all engines should make for pressure
But the general rule is 10psi per 1000 rpm


Do not run 5w30 unless your engine builder says to. Gm specs that from the factory because of reasonably tight stock bearing tolerances, and because it works for a very broad range of climate conditions...it has almost nothing to do with the main oil passageways

soundengineer

iTrader: (16)

Also, 15-50 is not really all that thick...
In cold weather its not going to work well at all and may cause problems...
But in a warm climate, its not an issue.

baezi z06

iTrader: (2)

Hi

i did build my motor my self for bigger shots of nitrous

and i saw the same psi numbers as you on the motor last summer on the vr1 10-30 non syn (as also was recomended for my engine) after break in
i was seeing 25-30 idel hot 40-45 cruising hot and only around 50-55 wot

but now i have installed a new BOSCH oil filter the distance plus + vr1 10-30 oil and a new vacuum pump

and now i ´m seeing similuar number idel and cruise but it doesn´t go higher then 40-45psi at 6500 rpm 8-10" of vacuum (oil psi didn´t change from 6 up to 10")

SOMbitch

iTrader: (8)

Erik told me to run 15w-50 in motor in sig....

RezinTexas

do you know what your clearances are? thanks!

99fbodyTA

5w30 synthetic mobil1

soundengineer

iTrader: (16)

you wont see quite as high of pressure with the vacuum pump
I have a similar small pressure drop with the vacuum pump on my car...

baezi z06

iTrader: (2)

i went out for a little drive in the rain

did a bit of testing

took the belt of the pump and i´m getting 50-52psi whith belt off i´m loosing 7psi from the vacuum pump

i set the valve relife at 5" first and then up to 11" of vacuum and it didn´t change it´s was always between 40-45psi at 6000-6500rpm whith the vacuum pump running


baezi

96capricemgr

iTrader: (1)

Do you yet understand that oil pressure is unimportant and FLOW is what is necessary.

Seems to me the lower crankcase pressure is just allowing the oil to flow easier getting the same VOLUME across the bearings without the restriction of additional PSI which can just trigger the bypass and reduce flow across the bearings.

Bearings work much like hydroplaning the car in standing water, it is not pressure that keeps things separated.

Iceman02

iTrader: (1)

Pennzoil Platinum 5w-30.

96capricemgr

iTrader: (1)

http://www.bobistheoilguy.com/forums/ubbthreads.php
is a good place to get oil info based on measured results.

soundengineer

iTrader: (16)

He's not asking for oil comparisons,
He's asking what viscosity based on bearing clearances for how the motor is built...

Loose motor vs tight factory motor...not brand A vs brand B