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Hey guys, my name is Stewart and I have an 85 mk2 Supra that I am going to be 7mgte swapping over the winter and spring. For the last month I have combed over multiple forums and hundreds of threads about how tp properly address the issues that are typically associated with having a 7m, my question is oil pressure/pump related. I am planning on getting rid of the stock pressure regulated oil cooler and running a thermostat controlled aftermarket oil cooler setup. But what I am having a great deal of issue figuring out what to do about the 5m oil pump, there is so much back and fourth on posts about shimming and its positives and negatives I'm not sure what to do.
My question is: If i have a WITHIN SPEC stock oil pump and thermostatically controlled oil cooling setup with a relocated oil filter is there a need to shim the oil pump for engine longevity or will the stock pressures be adequate to keep this engine going for a long time into the future ? Power goals are fairly tame, basic bolt ons FMIC, Exhaust, 10psi of boost (or less) etc.
 

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It is up to you. Most people, including myself, shim it a light amount. Like 2 washers thickness. The oil squirters at the bottom of the bores bleed off oil, as does the turbocharger. So that is 7 items receiving oil on the tubo engine, that N/A doesnt see. Would be 8, but your eliminating the stock oil cooler setup.

If you do shim the pump, dont go crazy, otherwise you will encounter exploding oil filters. Not kidding.
 

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Im still planning on running an oil cooler, just a better quality aftermarket one. Beyond blowing an oil filter from over shimming is there any other negatives associated with shimming an oil pump even a light amount (2-4mm) ? Im just wanting to have this engine life be as long as possible I like to drive my cars on the harder side.
 

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The exploding oil filter would be if it is shimmed too much. I had it happen once. Cold start PSi was ~80psi, and I reved it before it warmed up and it popped the pinched seam of the filter and shot oil everywhere in a rather spectacular fashion. I turned it off immediately. Dropped the pan and pulled all but 2 of the washers out. Then it was ~20psi idle when warm, and did not cause the filter to explode any more.
 

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Thanks for the advice, after doing some digging Driftmotion offers a brand new OEM front sump pump for the 7m thats made exactly for these swaps. The gears are Molly coated and the pump comes pre shimmed sounds like exactly what I need.
 

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Its a 89+ cressida pump. Not sure why they would moly coat the gears etc... though. Pre shimmed is nice. as they have tested the amount they shimmed it I am sure.
 

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I think the idea is that it makes the clearances even tighter, but i'm not really sure how much that is. do you know if a 89+ cressy pump pickup be in the same location depth wise as an 85 5m pump and 85 pan ? Im wanting it to be as deep as possible in the pan so there isn't potential oil starvation issues.
 

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Yes. I bought a 89+ Cressida pump for my 7mgte rebuild. Same as the deep 5m pump.
 

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I don't understand why the "shimming the oil pump" thing is still a "thing".

The valve in the oil pump is a pressure relief valve for when the oil is COLD, used to prevent filters popping etc.

However, when the oil is hot, the pressure are no where NEAR high enough to activate the valve or be bypassed (stock pressures are only 4.2+ psi at idle when HOT) Shimming the pump is only going to cause HIGHER cold pressures and increase the likey hood of damage due to excessive oil pressure.

If you're worried about oil pressure, run a 0W40 and leave the pump alone.

At least in my opinion.
 

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Your wrong. The valve is not a on/off solenoid, it is controlled by a spring. The piston moves in a linear motion, and even when the oil is hot, it still bleeds oil pressure off. That is why you can shim the pump and go from ~5psi warm oil pressure at idle, to ~20psi warm oil pressure at idle. I know, I have done it, on multiple engines. Real world testing and confirmation, and I am not the only one to have this result either.
 

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William,

I shimmed a brand new pump for giggles when I built my 7M and I STILL saw 5-6 psi at idle when hot with a 5w30. However, I did notice a HUGE difference in the cold idle pressure.

Going to a 10W60 (with a hot viscosity rating of almost EXACTLY double the 5w30 i was using) I saw a 5psi gain in pressures when hot without changing the spring. Meaning the valve wasn't bleeding the pressure away in any sort of linear fashion as you describe.

There is no way Toyota would design a bypass valve that would negatively affect the low oil pressure of the motor. It makes no sense and physically, unless we're talking about a SUPER weak spring, it wouldn't happen. The TSRM even describes the valve as I mentioned:

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=LU&P=3

A spring designed to bleed pressure beyond, say, 60psi simply will not start to move at 10psi.

Perhaps your issues were due to bad pumps.

Sorry man, I don't buy it, but I'm glad it worked for you.

If you're talking about the oil-cooler, then yes... it is notorious for bleeding pressure even when hot. However, the relief valve IN the pump is not designed in that fashion and unless its faulty, you shouldn't see that kind of behaviour.
 

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Yes, shim it. I bought the Driftmotion 7M shimmed oil pump and have had no issues. I'm also running ran the same setup you're talking about for 3 years no problems.

Let me clarify, we *did* have to trim some of the original baffles in the 5M Pan, AND also had to cut and reweld the pickup to fit the pan properly.
 

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You obviously have other issues with your motor if your oil pressure did not increase. The first engine I did, I didnt even replace the check valve bolts for the squirters that have the springs in them, and it jumped to ~20psi. Im betting at minimum you have the stock oil cooler adapter on the block, and the valve is stuck open dropping your pressure. It isnt supposed to flow until like 40+ psi. I got rid of mine altogether when I installed the remote oil filter mount. You do realize there are dozens of posts on Supraforums from people that have done this and confirm it works right?

Also, I see your on an 83, so that would have the low volume oil pump and shallow pan. The 84+ deep pan and pump are the same volume as the 7mgte. These high volume pumps are the ones it has been tested on extensively.

William,

I shimmed a brand new pump for giggles when I built my 7M and I STILL saw 5-6 psi at idle when hot with a 5w30. However, I did notice a HUGE difference in the cold idle pressure.

Going to a 10W60 (with a hot viscosity rating of almost EXACTLY double the 5w30 i was using) I saw a 5psi gain in pressures when hot without changing the spring. Meaning the valve wasn't bleeding the pressure away in any sort of linear fashion as you describe.

There is no way Toyota would design a bypass valve that would negatively affect the low oil pressure of the motor. It makes no sense and physically, unless we're talking about a SUPER weak spring, it wouldn't happen. The TSRM even describes the valve as I mentioned:

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=LU&P=3

A spring designed to bleed pressure beyond, say, 60psi simply will not start to move at 10psi.

Perhaps your issues were due to bad pumps.

Sorry man, I don't buy it, but I'm glad it worked for you.

If you're talking about the oil-cooler, then yes... it is notorious for bleeding pressure even when hot. However, the relief valve IN the pump is not designed in that fashion and unless its faulty, you shouldn't see that kind of behaviour.
 
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