CEF33Y

Tell me about it! My brother has a 2jz JZX 90, and runs pretty much a single breather hose into an always empty coke bottle. I'd never thought much about the oil being forced though the valve stems into the combustion chamber. I think while I'm welding the head drain/vent fitting to the sump, I might add another couple of fittings for some more vents.

See, this is why I still come here. Actual info/feedback. Awesome. Ahh, that makes sense re filter now that I think about it. So, still my fault, as I kept thrashing with excessive blowby 😆. The top of the pistons are "black" I need to update this with some photos. Is there a direct correlation between compression and blowby? I.e I didn't think 150ish compression was bad. (Even though the FSM quotes compression to be 174psi/300rpm) The restrictors/head studs etc was in prep for the elite 2500+ flex sensor install, so still going ahead, just need to sort out the bottom end first. Rabbit hole well and truly breached... haha.

Thread bump! Engine/Car: RB25DET Type of failure: Broken ring lands, damaged rod bearing Factors influencing the failure: Possibly self inflicted, I made changes AFTER I had it tuned... Pod filter replaced airbox State of tune of the engine: 265rwkw. Vipec plugin, hypergear turbo, 750cc injectors, 255 fuel pump, direct FP feed, cooler, exhaust, remote oil cooler. Suspension and tyres: Drift setup Oil used and service interval: Penrite 10 10ths 10-40w changed prior to every track day (<1000km) General comments: Bit of a weird one. Car has had blowby (only on the track) since I had it tuned. It's a street/drift car. Street driving it is fine, doesn't use/burn oil. On the track, I was filling my 500ml (yes, I know it's a bit small) catch can in 5 laps of QR big track. Compression was 152-156 across all 6. 265rwkw, 20psi, car still ripped. I assumed blowby was just RB things. Tried splash covers and mines style sponges under the rocker covers. No change. Planned to pull the head off, do restrictors, head drain/vent and head studs, new gasket. Got head off, and No.6 had some det evidence and the slightest deformation on the exhaust side of piston. All bores look pretty good, with cross hatching still visible in parts . Motor was out of the car, so pulled No.6 to have a look, and a chunk of ringland was loose, between rings, about 40mm long. No.5 was the same No.3 and 4 were ok No.2 Broken same as 5,6 No.1 cracked (1 vertical crack in ringland) No.2 rod bearing was showing some copper (still feels smooth, crank feels ok also), the other bearings look good. I have no Idea how it was still running, let alone drifting. Last drift's were pretty full on (QR matsuri) but did about 500km of street driving since that. Now after it was tuned, I changed the air filter from an airbox, to a shielded pod filter. Seat of the pants it felt the same, and audibly couldn't hear any det, but I may have caused this one I reckon. I'm guessing it' had some lean condition/Det, and that's what caused the broken ringlands. No.2 rod bearing is a bit odd though, why only No.2? Still in teardown and measure stage, to work out next steps.

Stock (old!) CAS, It is very inconsistent. will try the timing check and see what I can find. Thanks

Thanks guys, Yes I have a spare input and pressure sensor, will set it up for fuel pressure and see what its doing.

Not over boosting, boost control is setup through ecu, but have a gauge with recall, I’ve seen 21-22psi before. When it pinged, didn’t get there, was around 17psi. Yep that’s the train of thought I’m on. (Fuel supply) Will sort out a fuel pressure gauge, I think my Defi meter has provisions for another pressure sensor, will also check voltage getting to pump. Thanks

Hey guys. Have an issue with my r33. Lately (last 2 tanks) has been Randomly pinging/ knocking on boost. When I first heard it, backed off straight away. Temps seemed fine and was driving fine off boost, almost as it hit full boost, would ping. Suspecting shit fuel, put in some octane booster, and that seemed to fix it. Fueled up at a different servo, and was going better than ever, zero knocks. Put it down to shit fuel. Current Tank is about 1/4 full, rolled on in third coming home tonight and it pinged again. Car drives fine, and exactly the same everywhere else, no strange noises, temp is fine. Car has a Vipec plugin, deutchworks 255l/h fuel pump with 14v feed, splitfires, hyper gear turbo, pretty basic setup. 260ish rwkw, Tuned by Mitch (of haltech) Car has been the same for the last 2.5 years, parts were new (apart from ecu) at tune time. Both times it’s happened now, it’s been between 1/4tank and a 1/3 tank of fuel, unsure if that’s linked. Initially thought maybe a shit fuel pump, but thought that would be more consistent From what I gather the Vipec plug ins don’t have knock protection? Either that if mines not setup. Will have to head back to tuners I think. I’m guessing if I can hear knock, it’s probably already doing damage. After first tank with knocking, pulled plugs out (all looked normal) and did compression test, 165-170 across all 6. Top of pistons looked unmarked. Bloody intermittent issues! Anyone had a similar intermittent knocking issues/things I should check? Cheers

Looks like it would blow the tires off at lower RPM. Excellent.

Hey guys, feel free to add any info to the thread if you feel its relevant, thats the best part about forums. So, updating, as the box is back in the car, and to give the thread some closure. Much anticipation I started car, and slowly released clutch, aaaand the noise is still there. Bugger. Probably a bit better, but hasn't "fixed" the noise. So ultimately its got to be the gearset. I also put a new syncro in 2nd gear, and the shift into second feels better, so along with the experience of actually rebuilding a box, it wasn't a complete waste of time (pretty close though, haha). Plan from here is to keep driving/drifting with this box until it lets go, then probably buy new. I don't think "low km second hand" boxes exist anymore. And I'm not making the power where I think a gearset is warranted. Thanks for the advice/help guys

Bit late to reply, But yeah, the CBC kit I got came with the sealed bearings, on which I've removed the seals. Just got it back together last night, hope to have it back in the car tomorrow. Pretty happy with the CBC kit, even came with 1st gear bush (which looked average on mine, burred on the edge where it looks like they've used an ill fitting pipe to drive it on). Someone has had this apart before and did a average job putting it back together. The needle bearings on 1st and 2nd gear felt terrible as I was pulling it down, and popped the seal off the (old) bearing in the center plate and there was alot of black deposit, and the oil in there was much darker than the oil drained from the Gbox. Anyway, will see if the gbox noise has gone soon enough!

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sold pending

Well yeah, that's right, there are not many "cheaper" options. Most things across the board have gone up. Just means if I bend it in half I'll cry alot, not a little

Guys I've got a used Velo GPT-2 fixed back for sale. (see Velo site for size chart, GPT-2 is XL) Its just too tight for me. Its in fair condition (one small, 5mm hole in material), missing the bottom cushions, which can be bought from Velo. Structurally its good. Comes with alloy side mounts. Located Bomaderry/Wollongong. $300

You know, while I should be happy about the value of my car going up (way up!) I use mine as a street/drift car, and I've always had a mental limit of $10k for cars I take on the track (incase I bend it). I kinda have second thoughts thrashing the ring out of it now! Oh and to the OP, like others have said, double the purchase price of the car, that's what the true cost will be.

Hey guys, so in the middle of pulling apart my R33 gearbox. It was noisy in first and second gear, third and forth noise pretty much goes away. I’m up to pulling speedo drive sleeve off, but have to modify my puller set to fit, so it’s not fully pulled down yet. The question I have for now, the input shaft bearing and the bigger bearing in the centre plate are rubber sealed bearings. Now, from all the googling I’ve done, I’ve not come across any pics of sealed bearings. I would have thought the bearings need to be open to ensure adequate lubrication. I mean, the factory Nissan bearing is open... The input bearing feels ok by hand, keen to see what the one in the center plate feels like. Any gearbox guru’s have any thoughts on the use of sealed bearings? cheers

Ahh, that makes sense

We use a similar flexible heatshield product at work. As you are trying to keep the heat in the manifolds, shouldn't the shiny side be facing the manifold?

Bingo. Bled it one more time, on ground this time. Then I drove it to work (50mins drive), then went to a mates place after work, (25 min drive through traffic), got to his place, opened bonnet, felt hose top hose which felt like it had some pressure, opened rad cap (carefully!) and sprayed coolant out. I'm guessing it just took another bleed/couple of drives to get all of the air out. Tested it while hot and it holds pressure. Thanks for the reply's guys

Do have a mate with a cooling system pressure tester, might be worth a test.

Guys, Basically, at what sort of water temperature would you expect to see pressure in the cooling system? I've got a nismo thermostat, stock, but 5 y/o radiator, stock clutch fan and rad shroud. Remote oil cooler (keeping factory oil cooler/warmer under oil filter). Ambient temperature of 22-25 and I see water temps of 71-75 and oil temp the same, I can open the rad cap at these temps and there is no pressure. Coolant level still at top of rad. Recently changed water pump, and 0.9bar radiator cap and bled it correctly (car jacked up, heater on, bleed screw open, cut down bottle in top of rad, etc etc), took it for a drive up cambewarra mountain (basically a steepish, 6km hill) giving it a hard time, with air con on, and ambient temp of 42 (last weekend!) and it only just nudged 92 degrees at the top. By the time I'd got back home, it was at 75 deg, overflow bottle level went from half to 3/4. Opened cap and zero pressure. Oil temps seem to mirror what the water temp is doing Its also a drift car, and normally takes 5-7 passes before it hits 95ish, usually sitting in staging lane, it will fall to mid 80's within a few minutes. From memory car has been like this for a long time, but as its never overheated and uses no coolant, runs perfectly fine, no oil/water mix in either oil or coolant side. I haven't though too much of it, but having just done the water pump I was paying a bit more attention to it, and thought its strange. Even at 70 degrees, I would have expected a bit of a pssht when opening the cap? Thoughts?

Enjoying this thread, especially all the gearbag tip and pics! I've got a noisy RB25 box, (whine in 1st and 2nd, when on/off power) planning to pull it down, hoping its just bearings. Threads like this are what make forums great. Keep up the great work

Have you checked the switch on the brake pedal re. your cruise control issues? mine was out of adjustment, allowing the cruise to turn on, but not actually activate, i.e, hold a speed

Mate, this thread is awesome, hanging for the next install. Always been (still am) a turbo Nissan kinda guy, but do have a vy ss crewman as a daily/ work car, and I quite like that too!

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