DanielH

I have fitted my oil cooler/filter relocation kit and oil temp/pressure gauges and serviced with Penrite 20/70 (hpr30) mineral, a local tuner recommended I try Fuchs 25/70 so i went with availability at the time and got a similar grade in Penrite. I gave it a hard time on the dyno tonight, got the oil up to 105 Celsius and gave it full power runs to the limiter every time, no issues at all, maintained 5-5.5 bar of oil pressure under load at that temperature. Unfortunately I did it all at once and have no previous data on oil temp/pressure, but the whole setup seems to work very well now.

I'm looking at it in the sense that the lifters have an inbuilt 1 way valve which should prevent them from bleeding down at all, ever. However with carbon getting trapped in there and possible thinning oil I'm assuming its just always gonna happen at times under given circumstances, and rather than trying to "pump them up" and get maximum oil flow into the lifter, I'm thinking of what could prevent the oil from escaping from the lifter when the cam lobe slams against it time after time. Cause realistically the forces applied to the lifter are gonna be far greater than the ~80psi of oil pressure inside the motor, which is no doubt alot less after it passes through the restrictors.

I've been running rb20 and z32 afm's blow-through for years now with no apparent issues, I always run them in the cold side just near the throttle body, behind the headlight with a forward facing intake, wouldn't have it any other way. My current setup is a forged rb25 in a commodore with a greddy intake, gt3076, big cams etc, brand new genuine z32 afm mounted about 30cm from throttle body and its making 307kw at the wheels on 21psi and the afm is only at approx 4.8v, couldn't even dream of it ever stalling and ive had no problems doing this what soever, with exception to needing to brace the piping to stop it from blowing off the plastic.

I went with the thicker oil seeing as though my problem only rears its head when everything including the oil is fully hot, and presumably thinned out, went with the mineral oil due to price and availability at the time, it doesn't see the track, with exception to powercruise where it will see a bit of abuse but nothing like a drift/track car.

Also I previously had completely isolated it engine temp, after the engine had completely heat soaked after numerous dyno runs or sustained load on the road it would start to tick. You can see the little dip in power right at the end of the run.

Have fitted a cooler/relocation kit and my gauges as seen below. Have yet to drive the car and test any changes but I have just over 5 bar of oil pressure when cold at 1000rpm, drops to just above 4 when warm, and sits on about 5.5 at higher engine speeds. Has anyone got any rough guidelines on a good safe oil temp for 20/70 mineral oil? It's Penrite hpr30. Also the coolant temp gauge sender was not connected in the photo.

Don't forget your car is tuned to have the VCT working, with it turned off the tune would be way off and the cam profile probably wouldn't work that well either, my cams are designed to be used in a fixed situation and you don't notice it, once the turbo hits its on, in my case it's just wheelspin everywhere for the first 3 gears!

The cams are a drop-in hydraulic cam for an rb20det, I think you're right about the oil cooler situation, and I opted for these cams because the car (VS commodore ute) was already running an rb20det, I got the car and put together the rb25 so it would be a "drop in" plug and play affair, already had the nistune so it was just a matter of running all the rb20 accessories, some gtr injectors, give it a tune and call it a day, I really wanted the aggressive idle and a bit of an increase in top end was always a bonus. It's running a big equal length highmount manifold, gt3076 with .86 rear and a greddy intake, it was never gonna be like a stock 25 and I love the way it goes, it's so aggressive, tons of fun to drive, I just need to sort out this problem. I'm gonna slap the cooler on as quick as I can with some gauges and put some good oil in it, if that doesn't work ill disassemble and clean up a spare set of lifters and swap them in.

I might just play it safe and smash one of my oil coolers on it, least ill have somewhere to fit my gauge senders.

This is another issue I was trying to figure out, the only adapters I have for the filter are oil cooler kits with filter relocation, no sandwich plates, I don't really have the room in the engine bay or the time to fit an oil cooler kit in the next few weeks so that's a last resort, if I can identify the oil is getting hot.

Yeah I'll get onto it as soon as I can, powercruise is in 2 weeks here and I don't wanna have to put standard cams in as a last ditch effort Ill look some more into different oils and try that, failing that ill have to pull the lifters apart and clean/inspect them all. Thanks mate.

Yeah plenty of oil getting to the head, and yeah the rings have all-but seated so ill give it a service soon, can anyone recommend an oil that will possibly help keep the lifters pumped up a bit better? And I'm not currently running a cooler, or the factory heat exchanger, that was my concern but then the oil hasn't shown any signs of being burnt? I have oil temp and pressure gauges to put on it soon and get a better idea of what's going on in there.

I did mention the oil weight, which is 15w40, the head was reconditioned and had the cams/springs fitted a fair while ago, the lifters haven't been touched in a long time, the bottom end has only done around 3-4 hours work. I chose these cams because I'm running an rb20 loom/ecu, already had tomei adjustable cam gears and just wanted the simplicity of it, it's just a street car, I love the way it drives I just need to sort out the lifter issue. They have no issues pumping up, they pump back up fairly quickly if I hold it on around 2000rpm.

Also do you have cams? I think the 272's are possibly playing a big role in putting extra load on the lifters and maybe causing valve float.

Sorry I left them out because there is nothing changed. its stock apart from what I mentioned, low K's stock rb25 pump with wide drive collar fitted, stock restrictors, forgot to mention no VCT (rb20 cams). The sump breather is fitted to the inlet side at the top of the sump near the engine mount and baffled to keep the oil out, works well at venting the crankcase. Shell 15w40 oil. I'm trying to get onto the gauge as soon as I can. How hard do you push your car? What kind of rpm do you push it to and do you hold it there for long? Thanks mate.

Hey guys, just finished tuning my self-built rb25 and I am having problems with the lifters bleeding out and ticking after sustained rpm. Mods list as follows: Stock bottom end fully rebuilt with Ross forgies Oil pump collar Shimmed oil relief valve in pump Camtech 272/9mm cams with performance springs 5/8" baffled sump breather plumbed into original location for PCV, both cam covers vented to a catch can. Oil slightly overfilled. I have searched and searched but found no definitive answers on what could be the main cause for this, the best advice I've had so far suggests the valve springs are getting soft when they get hot causing valve float, but I would have thought this would cause me lifter pump-up, not bleed them dry and cause loud ticking. I am currently running shell mineral oil as the engine is still young and the rings aren't fully seated, but the oil is still clean and doesn't smell burnt. It is tuned on 21psi and probably somewhere around 250-300kw, it's not in a drift car but it cops a hard time on the street, the limiter is set to 7k and this happens after back to back runs pulling to the limiter and ripping skids. I'm not convinced that this isn't something to do with oil thinning out or oil starvation yet, but stupidly I don't have an oil pressure gauge on the car right now. Any help would be greatly appreciated, sorry for the long post. Daniel

PM replied!

Urgently after 1 r33 rb25de piston or bottom end, busted bottom end, anything! If anyone has anything send me a text or pm 0408 117 171

Wtb: 180sx front bar, prefer stock S13 front end parts, to convert 180sx to s13 front Sr20 aftermarket low mount manifold, cracked and cheap would be fine 180sx headlights or Just the motor assemblies Z32 aftermarket front bar SMS on 0408 117 171 Cheers Daniel

Hey mate I have a brand new URAS FRP front bar, it's massive though, $200 if you're keen 0408 117 171

Hey pipster11 I have one with real good tread I think it's an Ingens a1, $50 if you want it, send me a text on 0408117171 if you do and I'll see if I can find it

Its forsale, hes got $3600 on it on gumtree

yeah for road use aswell as track! its perfectly safe, absolute worst case scenario is it would crack and the tire would go flat.

$300 even, last i checked i was looking at around $1200 plus postage for a set ?? id be hell keen for 2 or 4 at $150 a piece!!

I dont think many people like to reuse bearings, unless its just a shitter/slapper! mind you i have reused healthy main bearings before in cars i have driven hard with no issues, but ive been bitten by being slack with big-ends in the past and now replace them before using any second-hand engine! I always use ACL Race Series bearings and they are good for the bang-to-buck ratio IMO, they're about $70 a set IIRC. I must have missed something here cause last i knew you had a forged 25/30 in your skyrine!!?