Tomei oil pump pressures - GT-R Register - Official Nissan Skyline and GTR Owners Club forum

Listerofsmeg · 12th July 2008, 02:11 PM

Ok, ive had a tomei oil pump fitted to my new engine, when starting the car up the (admitedly standard dash pressure guage) goes up to 5 bar cold. When warm is drops back down to just over 2 bar. When driving it sits around 4 bar and tracks up when you accelerate as you would expect.

My question is, i was led to believe that Tomei pumps push high pressures than standard for a given situation, so for example, 6-7 bar cold and 3-4bar warm idle etc..

So my question is, am i wrong? is this normal? the engine sounds fine with no nasty noises....but the way everyone raves about the tomei pumps i was somehow expecting more?

I have done a compression check to see if i was getting any blowby, and the result was 160-162psi across the board, so everything seems fine there.

so what pressures do you see with your Tomei pumps? cold/warm idle? and normal driving...?

kismetcapitan · 12th July 2008, 03:01 PM

how many discs did you install? You need to install all three to get max flow.

There's an upside. You have enough oil pressure. More flow means you can empty your sump faster. Empty sumps are very bad.

My engine block is done, and is going into my car next week. I am thinking of maybe adding ONE disc. The JUN pump I had before would suck the sump dry (and pull air) if the oil wasn't 100% topped off to the hump past the max line. A Tomei maxed out on all three discs would probably be the same.

Listerofsmeg · 12th July 2008, 03:07 PM

i did not build the engine, so not sure, my sump is around 10 litre so id hope it wouldnt suck that dry!! perhaps then its spot on, i guess i just need some clarification, my spec may be fairly unique...so getting that may be tricky!

Cheers for your input tho.

sloathy · 13th July 2008, 09:27 AM

10 litre sump

kismetcapitan · 13th July 2008, 12:16 PM

10 liters!! My car takes 8, but only half of that is in the sump - 2 liters in the oil cooler circuit and 2 in the Accusump circuit.

I have every Tomei oil mod except the Tomei sump. $2K feels a little rich for my blood!

trickymex · 13th July 2008, 01:08 PM

i get similer results but its never droped below about 3 bar, if i blip the throttle on cold start it goes upto 8 bar

Listerofsmeg · 13th July 2008, 03:09 PM

cheers trickymex, when i blip the pedal on cold start it will go up to 6, but nothing higher than that. At the moment its only running on 10w40 mineral oil for bed in, perhaps that can also affect pressures i dont know. I guess i should really invest in a better gauge! I took it out for a better drive today to get it properly warm and it all seems fine, my map is way out though so i was being very careful.

frostmotorsport · 13th July 2008, 11:10 PM

Lister (or is it smeg??

) has touched on the key here - your oil - the weight and how new it is will dictate to a degree what your cold and hot pressures are. on a stock pump I get 3bar at cruise, 2.5bar at idle and 4+ bar when boosting on hot oil. cold pressures are significantly higher (6 bar off boost)

just recently put fresh oil on 15W-40 which has increased pressures noticibly, and makes the pressure more 'sensitive' to RPMs...

chaz_r33_gtr · 14th July 2008, 08:29 PM

I got a tomei pump on mine after full engine rebuild and get the same results

cold idle just over 4bar, blip the throttle and it goes up to just over 6bar
warm idle just over 2bar, and driving on boost just over 4bar.

This is on Fuchs Pro R race oil 5w 50 i think, I have a tomei sump baffle and greddy 16 row oil cooler too.

RB motorsport rebuilt mine so i guess they didnt put all three discs in the oil pump. I also have the tomeil oil restrictor fitted to stop too much oil being sent to the cams.

alex2005 · 14th July 2008, 09:33 PM

Oil pressure depends on the Oil clearances on the shells quite alot aswell, the larger the clarence the lower the pressure, most tuners would prefer to have a lose engine over tight clearances anyway, and high pressures are not always such a good thing.
After rebuilding my engine with a JUN oil pump and tomei restrictor running 15w40 mineral oil my oil pressures are 6bar cold 2.5bar hot at idle and while driving with oil temp between 80-90deg 3k-5k rpm pressure doesnt drop below 4.5bar but as soon as I have finished bedding in I will be running 10w60 fully syn and I will see what difference that makes.

All my readings are using the standard R32 pressure gauge witch are know to be quite inaccurate so it will be making way for a Blitz unit.

12th July 2008, 02:11 PM	#1 (permalink)
Listerofsmeg GTROC Member Join Date: Jul 2006 Location: Shefford, Beds Posts: 1,850	Tomei oil pump pressures Ok, ive had a tomei oil pump fitted to my new engine, when starting the car up the (admitedly standard dash pressure guage) goes up to 5 bar cold. When warm is drops back down to just over 2 bar. When driving it sits around 4 bar and tracks up when you accelerate as you would expect. My question is, i was led to believe that Tomei pumps push high pressures than standard for a given situation, so for example, 6-7 bar cold and 3-4bar warm idle etc.. So my question is, am i wrong? is this normal? the engine sounds fine with no nasty noises....but the way everyone raves about the tomei pumps i was somehow expecting more? I have done a compression check to see if i was getting any blowby, and the result was 160-162psi across the board, so everything seems fine there. so what pressures do you see with your Tomei pumps? cold/warm idle? and normal driving...? __________________ White R33 GTR Its working!! 10.908 @ 128mph @ 1.6bar on pump fuel and full trim! 640bhp/509lbft @ 1.7bar

12th July 2008, 03:07 PM	#3 (permalink)
Listerofsmeg GTROC Member Join Date: Jul 2006 Location: Shefford, Beds Posts: 1,850	i did not build the engine, so not sure, my sump is around 10 litre so id hope it wouldnt suck that dry!! perhaps then its spot on, i guess i just need some clarification, my spec may be fairly unique...so getting that may be tricky! Cheers for your input tho. __________________ White R33 GTR Its working!! 10.908 @ 128mph @ 1.6bar on pump fuel and full trim! 640bhp/509lbft @ 1.7bar

13th July 2008, 03:09 PM	#7 (permalink)
Listerofsmeg GTROC Member Join Date: Jul 2006 Location: Shefford, Beds Posts: 1,850	cheers trickymex, when i blip the pedal on cold start it will go up to 6, but nothing higher than that. At the moment its only running on 10w40 mineral oil for bed in, perhaps that can also affect pressures i dont know. I guess i should really invest in a better gauge! I took it out for a better drive today to get it properly warm and it all seems fine, my map is way out though so i was being very careful. __________________ White R33 GTR Its working!! 10.908 @ 128mph @ 1.6bar on pump fuel and full trim! 640bhp/509lbft @ 1.7bar

14th July 2008, 09:33 PM	#10 (permalink)
alex2005 GTROC Member Join Date: Jun 2007 Location: In the Garage Posts: 635	Oil pressure depends on the Oil clearances on the shells quite alot aswell, the larger the clarence the lower the pressure, most tuners would prefer to have a lose engine over tight clearances anyway, and high pressures are not always such a good thing. After rebuilding my engine with a JUN oil pump and tomei restrictor running 15w40 mineral oil my oil pressures are 6bar cold 2.5bar hot at idle and while driving with oil temp between 80-90deg 3k-5k rpm pressure doesnt drop below 4.5bar but as soon as I have finished bedding in I will be running 10w60 fully syn and I will see what difference that makes. All my readings are using the standard R32 pressure gauge witch are know to be quite inaccurate so it will be making way for a Blitz unit. __________________ not just a car, a responsibility! My rebuild thread http://www.gtr.co.uk/forum/96129-r32-gtr-engine-bay-makeover-rebuild.html

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12th July 2008, 03:01 PM	#2 (permalink)
kismetcapitan GTR Register Member Join Date: Nov 2005 Location: Seoul Korea Posts: 6,608	how many discs did you install? You need to install all three to get max flow. There's an upside. You have enough oil pressure. More flow means you can empty your sump faster. Empty sumps are very bad. My engine block is done, and is going into my car next week. I am thinking of maybe adding ONE disc. The JUN pump I had before would suck the sump dry (and pull air) if the oil wasn't 100% topped off to the hump past the max line. A Tomei maxed out on all three discs would probably be the same.

13th July 2008, 09:27 AM	#4 (permalink)
sloathy GTROC Member Join Date: Jun 2006 Location: HERTFORDSHIRE Posts: 493	10 litre sump

13th July 2008, 12:16 PM	#5 (permalink)
kismetcapitan GTR Register Member Join Date: Nov 2005 Location: Seoul Korea Posts: 6,608	10 liters!! My car takes 8, but only half of that is in the sump - 2 liters in the oil cooler circuit and 2 in the Accusump circuit. I have every Tomei oil mod except the Tomei sump. $2K feels a little rich for my blood!

13th July 2008, 01:08 PM	#6 (permalink)
trickymex GTR Register Member Join Date: Nov 2007 Posts: 353	i get similer results but its never droped below about 3 bar, if i blip the throttle on cold start it goes upto 8 bar

13th July 2008, 11:10 PM	#8 (permalink)
frostmotorsport GTR Register Member Join Date: Aug 2007 Location: Wellington, NZ Posts: 784	Lister (or is it smeg?? ) has touched on the key here - your oil - the weight and how new it is will dictate to a degree what your cold and hot pressures are. on a stock pump I get 3bar at cruise, 2.5bar at idle and 4+ bar when boosting on hot oil. cold pressures are significantly higher (6 bar off boost) just recently put fresh oil on 15W-40 which has increased pressures noticibly, and makes the pressure more 'sensitive' to RPMs...

14th July 2008, 08:29 PM	#9 (permalink)
chaz_r33_gtr GTR Register Member Join Date: Aug 2005 Location: Lancashire Posts: 287	I got a tomei pump on mine after full engine rebuild and get the same results cold idle just over 4bar, blip the throttle and it goes up to just over 6bar warm idle just over 2bar, and driving on boost just over 4bar. This is on Fuchs Pro R race oil 5w 50 i think, I have a tomei sump baffle and greddy 16 row oil cooler too. RB motorsport rebuilt mine so i guess they didnt put all three discs in the oil pump. I also have the tomeil oil restrictor fitted to stop too much oil being sent to the cams.