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HI all,

Was wondering if I could please canvass the community's oil usage in the RB25DET's.

Could you please frame your responses to include:

Short list of Mods:

Fuel:

Power Level:

How long the motor has been burning noticable amounts of oil (500ml+ or more per service interval):

Any contributing factors you think started causing the oil burning/ accelerated wear on rings etc:

Top-up Frequency:

What oil used:

Preventative measures you currently have in place to minimise:

Any negative impacts including reduced power levels, impact to turbo compressor etc.:

Finally as a guestimate, i reckon 5mm on the dipstick may be equivalent to somewhere between 250-500ml.

Thanks

Stock VQ25det running a GTX3076 at 32psi

United Ethanol

350awkw

Mine burns through around 1L in 4000k's. I am not worried in the slightest as it never blows blue smoke, no drips and the catch can is nearly empty.

I am using the last of my GW Sougi 6000, and will be swapping to GW synx 6000 next change. I never check the dipstick as I overfill .5L and change every 4-5k.

Thanks Scotty, since the catch can is nearly empty, I take it that the oil consumption is predominantly from the oil not being scraped entirely off the cylinder walls and hence burning off in the combustion process?

Most likely, it is a common issue with the VQ's due to thin top rings for efficiency. The bores didn't look too bad when I had the heads off, but they weren't perfect. I have no choice but to live with it, as there are no aftermarket piston options for the VQ25det's.

Thanks ARTZ, great to see you're making that power without oil being consumed.

I'm after a consensus to determine what is reasonable in terms of oil consumption.

After a good fanging i gave my car, it seemed to use between 250-500ml just over a several days.

Running 300kw, e85, 19psi - new GTX3076 turbo.

Does anyone know if blowby (without a catchcan) will damage the turbo? (I want to protect my investment)

Thanks ARTZ, great to see you're making that power without oil being consumed.

I'm after a consensus to determine what is reasonable in terms of oil consumption.

After a good fanging i gave my car, it seemed to use between 250-500ml just over a several days.

Running 300kw, e85, 19psi - new GTX3076 turbo.

Does anyone know if blowby (without a catchcan) will damage the turbo? (I want to protect my investment)

yeah, im fairly nice to my car , it doesnt get limiter bashed much and its good low k engine too....

im pretty sure the small amount of oil can actually be good for your turbo...it is however not great for your AFRs...and it lines your intercooler with oil which isnt ideal either...

just get a catch can..doesn't have to be fancy, a 30$ can off ebay, plumb it inline with your oil breather pipe and fill with steel wool to catch oil..shouldn,t cost you more than 50$ish...leave your PCV intact...at least this way you can monitor your oil usage..

GTX3076 ( used to be) 320kw's running E85, has 180k's and using Mobil 1 oil for 50k's and adding Lucus Upper Cylinder lube in the fuel, ( 1/3bottle per tank)

uses no oil, i fill to the top of the H and it stays there til next change, and stays a nice gold clean colour

If you have the blowby recirculating, then i wonder if the compressor might be actually sucking in oil from the rocker covers???

GTX3076 ( used to be) 320kw's running E85, has 180k's and using Mobil 1 oil for 50k's and adding Lucus Upper Cylinder lube in the fuel, ( 1/3bottle per tank)

uses no oil, i fill to the top of the H and it stays there til next change, and stays a nice gold clean colour

If you have the blowby recirculating, then i wonder if the compressor might be actually sucking in oil from the rocker covers???

I didn't consider that.... can that even happen? Do you have a catch can?

1993 R33 GTS-T auto (so RB25DET S1)

With ~165,000km on odo (although most likely wound back at some stage)

Basic bolt ons (TBE, POD, Boost Tee & SAFC 2)

Last time on dyno (about 2-3 years ago) made ~180rwkw

Used to mainly use Caltex 98, now I mainly use Shell 98 (V-power)

Uses no noticable oil according to dipstick (last time I changed oil about 4.8L came out), oil gets changed every ~5000km with GW Synx-3000 (10w40), before that I had the car serviced regularly at the shop but I have no idea what brand of oil they put in.

Only thing I noticed is that my oil goes dark really fast, (within 500km of driving or so).

Edited by Mayuri Krab

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