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Clearances from the top of the gear to the oil pump cover also known as the side clearance(not body clearance which is side of gear teeth to body) is:

.0012 - .0035

On a rebuilt motor was previously running about 4-6 psi at idle when oil was warmed up on 10-30. Kid overheated the motor and through a rod.(no antifreeze). Anyway, I rebuilt the motor with reletivly the same specs as previous. But what did change was the oil pump. I had to take the oil pump apart the clean out the debris. While doing this I decided to take some measurments.

The body clearance was well within specs, but the side clearance(again top of gear to cap)was pretty close to the max(.0033), along with having many deep groves in the cap. I had the cap milled to a smooth finish. I then had the body milled until I achieved .0011, slightly under minimum clearance.

After installing motor, running it for a few hours with 10-30 oil, I was maintaining 30-35 psi at ~800 rpm. I forgot to check at 3,000 RPM, but I will do that tonight.

This was in a non-turbo, but as stated before, before the mod, it was 4-6 at idle.
 

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What is the oil pressure suposed to be at idle? I don't have access to the online TSRM at the moment... stupid web sense blocks it.
 

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greasemonkey
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was the pump shimmed? you didnt mention it so ill assume not.
 

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Escaped from infinite lag
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i shimmed my bypass spring and im running 3.5 kg/cm2 (dont know psi) at 3000rpm
 

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No clue about this... but sounds iteresting.

By Increasing oil pressure you recieve the benefit of?? Increased flow everywhere? If so isn't that much pressure a bad thing?
 

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i dont think there's a such thing as too much oil pressure unless you had an rx7..correct me if im wrong.

the oil would just flow faster...increasing cooling...decreasing a chance of rod k nock
 

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To much oil pressure can be a bad thing if the oil goes by things to fast it won't be able to absorbe heat. But to little pressure is even worse.
 

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Be original, not a copy
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Too much pressure is bad in that it requires a good deal of power to have that much pressure. Also, strain is put on the timing belt (which is driving the oil pump). It is generally thought that 10psi per 1000rpm is a desired pressure for performance use.

Doing this mod though will allow you to run a lower viscocity of oil which improves gas mileage, lubrication and heat rejection.
 

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Walking Dead...
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Wu_Tang said:
i dont think there's a such thing as too much oil pressure unless you had an rx7..correct me if im wrong.

the oil would just flow faster...increasing cooling...decreasing a chance of rod k nock
Yes there is! if you turn it up too high you are going to blow your cam and crank seals very quikly and nobody likes bleeding oil like a stuck pig, but it takes a lot to get to that point. Also the ammount of strain that you would be putting on the belt would be negligable at most. Being able to run a higher viscocity oil is a MAJOR plus of this mod. I would highly recommend to all 7mgte users, Toyo had a really bad idea when it came to the high vol low pressure stroke of genius.
 

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Lazarous said:
Yes there is! if you turn it up too high you are going to blow your cam and crank seals very quikly and nobody likes bleeding oil like a stuck pig, but it takes a lot to get to that point. Also the ammount of strain that you would be putting on the belt would be negligable at most. Being able to run a higher viscocity oil is a MAJOR plus of this mod. I would highly recommend to all 7mgte users, Toyo had a really bad idea when it came to the high vol low pressure stroke of genius.
???
Oil pressure would in no way put pressure on the crank seals and very little (if any) on the cam seals. Blow by pressure pushes on those seals. The strain on the belt with extremely high oil pressure is not "negligable at best" as the oil pump drive shaft pulley has a much lower contact patch (number of teeth) than the crank or cam pulley(s). Being able to run a higher viscocity is not a major plus of this mod. Running a LOWER viscocity is a major plus for this mod. Toyota did not have a "bad idea" as "high vol, low pressure" was not their idea. What Toyota did was have a "higher volume at the same pressure" pump. Which means that at 20psi the GTE pump will move a higher volume to compensate for the turbo and oil squirters which will maintain the pressure. Try putting a turbo oil pump into a GE motor without the oil squirters and turbo system and see what happens....pressure will rise.
 

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Red Rider
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the pump only displaces a certain amount of oil per turn. pressure is a byproduct of resistance to flow, that resistance can be through viscosity or tigher tolerances, changed relief springs or whatever

so if pressure is caused by resistance to flow then higher pressure means less flow to an extent
 
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