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hey guys

latly iv been noticing my gtr is dropping oil pressure on hard accelration

mainly first an second gear drops to bout 2 bar and have seen my preset warning light come on at 1 bar

only for bout a micro sec, asson as i change gears pressures back up

normal driving not probs what so ever or even building boost slowly

motor has just under 6000kms on it and dosnt make any wierd knocks

motor feels strong with no lose of power (332kws)

usally iv got 2.8bar of oil pressure at idle

and bout 5-6bar a 3000rpm

im running an

apexi oil pressure guage

tomei oil pump

tomei sump baffle

head restrictor

motul chrono 300v oil over filling stock sump with an extra litre

is this the common rb26 problem that i keep reading bout??

im just abit worried

thx guys

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How many litres do you put in the sump?

I put 6l in every oil change with a stock sump. I have seen this happen before, even 3rd gear full acceleration.

Even with the tomei baffle it happens, I'm suprised.

I'm seriously looking at a sump extension to help fix that problem, and a head to sump breather pipe.

6 litres in the sump on change,

im changing the oil on tuesday as its burnt a tiny bit of oil

it was the first time running full synthetic oil after run in

but on the tomei oil pump i left the oil pressure on the lowest setting (ie. didnt add any extra shims)

but where does 6 litres, or the extra litre get you on you on the dip stick? depends on oil cooler setup etc.

it should be on the bottom of the hump on the stick above the H mark.

i too have the tomei baffle but saw oil pressure drop on hard accel with the dipstick on H.

filled it up to the hump above H and no more pressure drop.

hmm, I personally would not be running a tomei pump without an extended sump. check the flow rates for the tomei pump and you will see it can empty the sump pretty quickly... JUN Tomei etc all strongly advise against running their pumps without increased sump capacity.

  • 2 years later...

Hi Guys

As part of my current build I will also be running a Tomei oil pump, ACL bearings (with an extra thou clearance) and sump extension (8L capacity). Unsure of oil weight as yet...

I am interested to know what oil pressure you're reading at say idle, 3k, 6k and 7.5k RPM?

Also those who doing track work what pressure drops are getting down to?

Reason I ask is am trying to figure out with EPC valve to run with Accusump....I found this doc from Canton, see link below:

http://cdn.racerpartswholesale.com/downloads/EPC%20FAQ.pdf

But just want to confirm the 35-40 psi valve is going to be the correct one??

Really unsure at which level of oil pressure (psi) I want the Accusump to open...35-40 psi Or 55-60 psi??

Cheers

i have 100psi at 7500rpm. nitto oil pump and running 20w50 torco sr1 oil.

Thanks mate. Appreciate that. Do you get any oil surge/drops in pressure?

Would be great to hear from others actually using an accusump and what EPC valve you're running...

Cheers

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