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Discussion Starter #1 (Edited)
In the morning when I start the car I will here a little knock for about 2 seconds until the oil gets up into the cylinders. What could be the cause? This problem is also intermittent.
 

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Are you sure it's knock? Is you IS a manual and if so have you done the bypassed the clutch saftey switch?
 

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if you have a built motor it could be piston slap if it was built too loose
 

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You don't want piston slap. Period! Have a friend start the car while you look under the hood. Check for lose parts that could of rattled lose. Could be something so simple.
 

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Discussion Starter #5
Im pretty sure it's knock...only for a quick second at start up. Im using 10w-40 oil now instead of 10w-30 maybe that could be the cause? I changed oil thickness thinking that it would help my blow by problem slightly, and it did.
 

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Im pretty sure it's knock...only for a quick second at start up. Im using 10w-40 oil now instead of 10w-30 maybe that could be the cause? I changed oil thickness thinking that it would help my blow by problem slightly, and it did.
10w-30? I thought our engines uses 5w-30.
 

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How cold are we talking about here? I run 10w-40 Amsoil and I get typical Canadian winter cold starts. No odd noises or knocking sounds :)
 

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A few here doesn't have much a clue about motors in general...LOL There is a guy running lesser oil than it should (probably to combat oil smoking problem from a bad turbo or something...haha), and we have a guy here to somehow thinks running a mix of different weight oil is a good thing. No offense to the folks, but I just want to know where you guys managed to get the info :)

Like SRT said, there are tons of built engines that need difference clearances from the pistons they are running... Slap can be perfectly normal depending on the piston, the cylinder liner material, and the type of driving the car is meant to do.

Running different weight oil just causes it to become unstable. Different polymers and ingredients are there to make the oil to sustain its flexible temperature rating, mixing them just causes problems. Almost under all circumstances, there is no reason to mix oil, especially synthetics, when you can have your desired viscosity rating out of the box. If you really need oil that heavy on the high-end, Castrol 10w-60. Lots of 800+ WHP Supras are running that. On my own cars, I have no need for that because all I did was install an external oil cooler and temps never reach to that point anyway.
 

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A friend of mine runs 8 qts in his supra. 7 qts VR1 20w50 1 qt lucas. (stock oil system and pan)

To each his own.

My old GTE block was near perfect, the shape the bearings were in were as close to new as you can get. (I'll try to find the photo i took)
 
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