BHDave

Tach out and engine light, thats about it. The rest comes from all over the place direct from sensors/senders like speed signal, oil pressure, manifold pressure, water temp, exhaust temp warning, battery voltage on gts's, handbrake warning and hicas warning/low ps fluid. They are all easily figured out/traced when looking at the back of the dash itself.

Jesus. Thats some kind of record

Why would one give more lag than the other? Does it have an extra 2 litres of internal volume? Id expect either would be fine for your goal as they are both name brand cores and good quality, assuming they are around the 600x300 core size (which is just about an industry standard these days)

I only threw in the cam gear comment as a general example of a possible cause. It isn't very likely. How much power did the car make with the old turbo? And when was the stock turbo hitting full boost and what boost were you running?

I think it's a long shot that rotating the housings has caused a problem, i've done it numerous times myself on that turbo, aswell as my new turbo with no problems. I'm only speculating that it is the box, it could be alot of things. You could have a cam out a tooth or slipped cam gear, could be a tired engine. The problem is that i'm in sydney and you're in perth and i'm trying to dagnose why the same turbo on the same type of engine is behaving in a completely different way to what it did on mine.

I drilled into the front and used a gear puller to get it off. Saves hitting shit with chisels. Mine was rusted on on the old rb20, not that you could see it until the gear was off. The rb25 one slid off and on easily.

It's 3mm vacuum/boost line. The factory one likes to split after you remove it. You can get 3-4mm tee's from supercheap. If they don't have the exact tee you need you can also get 3-4mm adapters.

Short of the box being absolutely rooted, i can't see how that would be the problem, maybe the torque converter is slipping excessively? Is it worth seeing a gearbox specialist to rule out gearbox issues? And the gcg highflows are capable of 250rwkw on rb25's so i don't see why 200+ isn't possible on an rb20 (and that's being conservative). The turbo made 199 on my rb25 at 14psi before i swapped it, that was only a couple of months before you got it. That was with 10:1 mixtures and no tune.

The pod shouldn't cause problems. They are one of the best flowing on the market. The pipes do suck in if they are a bit old and you are running a bit of boost, though it would have been spotted on the dyno i'd expect

good point, i should pay more attention. When you run less boost does it come on boost earlier? I'm just thinking about the stock rubber intake pipe sucking closed. Also, what sort of filter are you running?

Mine was just a single 1 piece dump/front pipe with a 3 inch catco cat and 80mm cat back with 2 mufflers. The wastegate couldn't be leaking after getting a knock in the post could it?

Yeah, manual gearbox. I had an HKS adjustable, but i can't see that being the whole of the problem. It was holding a consistant 12psi right through to the end of the run. This was on the stock ecu aswell, i got an emanage later on to run the 550's. I can't see the gearbox causing a difference of 500rpm in response, though it would effect overall power. What sort of exhaust? what size/and type of cat/ and how old is the cat? Have you tried dropping the exhaust by any chance?

Here you go, same turbo, different rb20 running 12psi, i remember now because i still had the stock injectors in it at this stage which is why the a/f ratio starts climbing at 6k, i added a couple of extra psi after i put 550's in.

I'll dig out my old dyno sheet for you tonight, it doesn't have boost on it unfortunately, can't remember if it was running 12 or 14psi at the time and made 174 or so rwkw. It was all in by 4200 or so on mine. It's also pretty obvious where the power starts on the graph as mine has the straight line followed by the big hump aswell.

If you've got the plugs out, do a comp test. It's worth the time to do it and you will know that your engine is relatively healthy. Checking the health of your engine is never a waste of time. new copper plugs will cost under 30 bucks. Get the timing checked on the dyno and adjusted at the same time if it's out, if it costs an extra 20 bucks over a regular power run i'd be surprised. Same for playing with the boost.

How far the rod extends depends on how much preload is wound into it (as the rod has to be extended to reach the pin on the wastegate flap even when closed). I had one but it's gone now, sorry. Have you tried wiring the waste gate open and seeing if you are getting boost creep due to too a small wastegate outlet or possibly the wastegate flap fouling on the dump?

It does, the stock reg is set to provide about 2.5bar (i think) base fuel pressure at atmospheric pressure. The vacuum/boost signal off the plenum maintains that set pressure differential by increasing/reducing the restiction in the fuel line created by the reg, so if you are running 1 bar boost at any given time, you will have the reg holding 3.5bar fuel pressure and you still have a 2.5bar difference in pressure. There are minor differences as it's a dynamic system and changes in flow (say by adding a bigger fuel pump) effect it a bit which is part of why you see a higher base pressure on the stock reg when running a higher flowing pump.

If i can offer one bit of advice it would be to ditch the stock afm and get a z32. Unless you've changed it since you took the engine bay picture. I'm partially colour blind but that looks like a green sticker which is rb20/25, orange is z32. Also the plug looks like the gray 20/25 plug. Cam gears shouldn't be needed with poncams as they are optomised to be a drop in cam. If you are getting full boost by 4k then i would be happy with the peak power figure. It would be worthwhile getting a run on a dyno dynamics dyno though so you have a figure comparable with everyone elses.

If youre popping out the dipstick you have a fair bit of blow by, which points to shagged rings. Under boost the pcv valve closes anyway, i doubt it's your problem. The big question is, how much oil is in the intake pipes?

Whats with the dip at about 100k's? Big missfire? If the dyno is saying you are running 11psi then i reckon your gauge is probably reading a bit high, My blitz dsbc reads very high. Everything else looks good. Swap your plugs for a set of bcpr6es, wind in a bit more boost, set your base timing to about 16btdc and try it again. In the meantime, do a compression test (while you are swapping the plugs). Your current setup is good for about 160rwkw on 13-14psi if your engine is healthy.

73.5psi is the pressure used for the rated flow of the 040 pump, whatever L/hr. Thats where the number comes from. Basically bosch state their pump will flow x L/s at a pressure of 73.5psi. Was the rising rate reg installed after all that discussion? I'd expect your pressure to be higher at idle and low load using the stock reg, and possibly slightly richer mixtures at he top end too as your old pump would have been getting a little tired. As for being under the rich and retard, at 10psi you would only be touching the edge of it anyway, at 12 you'll be into it, at 15 i'd expect you'd see mixtures well into the 9's, so by taking the 10% out at lower boost levels I expect you have acheived your goal. But please, tune the thing on a dyno, don't just go pulling fuel out and winding up the boost or you'll pop the thing soon enough.

If it turns out to be the pillow ball, pm me as i have a pair of HKS pillow ball fronts that you could have for a lot less than 400. Thet look like they are rebuildable by the way so if you can find replacement balls/carriers it will probably be cheaper again.

I plumbed my gate back in. Sounded too much like arse. Same manifold and gate, but with a T04s instead of e. The e has a much smaller comp housing so is pretty easy to fit compared to the s. Mines on a 25 though so can't really offer a comparison as far as lag.

I think you may have a very mismatched turbo. The rb20 exhaust housing is pretty tiny and so will start to cause a bit of restiction at the top end. On the other hand the early r33 turbos run the same exhaust and highflow versions of those make more than 220kw at much less boost. Then you have the T04E front wheel (Are you sure it isn't an S wheel) with what sounds like a T04s cover. These comps aren't particularly efficient at lower boost levels so you need to run higher boost to get the comp side of the turbo doing anything. I think you may have found the magical combo of a comp that will outflow the engine combined with an exhaust that can't flow enough to get it spinning. Before you do anything else (even swap exhaust housings) i would look at getting a T04E comp cover which have the more typical 2.5 inch inlet, 2 inch outlet and is about a .5A/R cover (i think). That should atleast get the thing doing what it should at much less boost, then get the exhaust side done. If i was sure you had an S comp wheel which matched your cover i would recommend you get a VG exhaust housing and you would have a pretty nice turbo.

You may as well put it on the engine. Exhaust side will probablky give the biggest gains, you are looking for about 4 degrees retarded. Play with the settings on the dyno, rather than just setting it and flogging the car as it may effect the mixtures enough to make it ping or run lean.