Cubes

Even 2000rpm isn't considered low rev's. I think the majority of us have got used to our high geared, high reving 6cylinders. The majority of cars cruise around at 1500-2000rpm all the time. Nothing wrong with that. Its all about load. You can cruise around at 1000rpm, its not damaging anything, put your foot in to it, go no where and it is likely to wear at a greater rate than if you were to do the same at say, 2000rpm. Just drive the car normally. Like a normal person drives. Thats all it requires.

RACESPEC, Its not the VG30ET turbine housing you want. Its the VG30DET turbine housing. Those you won't find easily. I don't see why the VG30ET housing wouldn't work as from memory its the same as the VLT housing. Only difference is it's not boltup.

See the Y axis PR value of 2 That is 15psi. 2.5PR is 22psi. As you can see this is nearing the top edge of the compressor map. The center island within the map is where the turbo is most efficient. Do engine airflow calcs and plot RPM's on the graph. At high rpm its best not to have the engine airflow heading out of the map (to the right obviously) as you will enter the choke zone. The choke zone is where the turbo is very bad at pushing air. Not efficient. This is what people mean by keep pushing boost in to it until it doesn't make any more power. At low rpm you don't want it to be boosting to the left of the map as this is the surge zone. Its a little complicated to workout the airflow, but not impossible. You need to take into consideration air temp, intercooler efficiency, volumetric efficiency etc.

Get the GT30 600hp core. Not the 500hp core. [/size] 700177-0014

You will find the rb20det hard to sell without manifolds etc so keep it complete. Maybe $200 or so?

http://www.google.com.au/search?hl=en&q=Ho...essor+map&meta=

Larger exhaust housings create less back pressure that improves top end VE. This in affect will help extend where peak power is made. A good example is the rb20 turbo on the rb30det. lol. Peak power is made by 4400rpm then goes flat and falls off rapidly after ~4900rpm. The larger exhaust housings raise peak power to around 5800-6000rpm. Back pressure = reversion. The stock log manifold = back pressure + unequal reversion. Which is why an equal length exhaust manifold is best for peak rpm power. So realistically if you want to keep the stock log manifold keep the cam specs mild. If you really want to extend your peak power you must not only do cams but also look at your exhaust manifold, ensure the turbo exhaust housing can handle the higher airflow at highrpm. Possibly why Roy's power looks so awesome. Nicely sized exhaust a/r equiv to .7 something from memory + a nice exhaust manifold. All he needs now is a nice set of cams.

Boost is not your friend, airflow is. If you are serious about building such a motor start googling and learn how to read compressor maps. You will see that the most you would want to run is from around 18-22psi absolute max. I wouldn't go below 8.5:1 personally.

8.5:1 is a nice number. Polish up the combustion chamber, remove all sharp edges and push it towards 9:1 if you want that little bit more response. At the end of the day 9:1 will handle 18psi without too many drama's.

Mine basically looks like a regular RB20/25 turbo, the comp wheel does look larger as there isn't the step up. I'll take some pics and post them. I've got a .82 exhaust housing that I will place next to it. The VG30 is definitely a .6 something not a .82. It will be interestering to put it next to the rb20 exhaust housing to compare the difference.

Trucks its a different story, they are constantly on boost. And if we are we shouldn't be. I've had my turbo for many many kays without the use of a Turbo timer. I don't sit my car idling, I simply turn it off as the last thing I do in the car. If I know I am coming to a stop soon I drive easy for the last km or so. Its clocked 187,000km's now to be exact. 120,000km's of its life it was running 1bar and only recently has it dropped back down to stock boost as it can't supply any more air to the rb30det without sending intake temps through the roof.

Interestering how peak rpm power stayed the same... Did the cams come with the specs, intake opening closing etc? Its a little sheet that should state something along the lines of IVO, IVC, EVO, EVC.

It doesn't work like that. When you machine a housing to suit you only machine out the hole for the exhaust wheel. Do a bit of googling on the process of highflowing and or machining exhaust housings.

FATGTS-R, Pulling the cat back off.. Be carefull it doesn't lean out as that is what it will do.

You still haven't told us what cams you are running. Now you have done cams you will find a nice little manifold will help top end not to mention mid range. Possibly a HKS Cast item? They are cheap and flow well. Excellent result.. Looks a lot like Roy's power curve. Roy what cams were you running? 170,000km's.. Doesn't suprise me, The little old RB's are tough.

I'll take photo's when I do mine in a week or two.

R34 GTR INJECTORS are SOLD!

You should be able to pick the test drivers. I sold a VS 5ltr 5speed commodore a while back. I had a few young wannabe's, I soon leartn to pick them.

Seriously check if it has blown a head gasket. Every one that looked at mine said it had an gave me big quotes for a repair. I had bubbles spewing out the overflow and it overheated every two seconds. It turned out to be a bad clutch fan, 2 x 12" Davis thermo's went on, summer came and the same happened again. I dropped a good clutch fan back on it and its been fine since. The RB20's are pretty tough and hardly ever pop headgaskets.

The RB20DET turbo shown is a series 2. The Series 2 turbo is ever so slightly larger. On the rb30det (rb25 head flows nice) my series 2 rb20det turbo made 176rwkw on 9psi. Its a good thing ppls.

Even when launching the way you did when it was making 200rwkw?

Pump Pics. First 2 are RB25DET pump, Second 2 are RB30ET pump.

Here it is.. Does 125km/h sound about right for 5000rpm on your dyno sheet Roy? Since the tune Darren is now able to take it to just before 7000rpm and it pulls all the way there. I'd like to see the new dyno sheet at 218rwkw and more top end, but there isn't one. If you ever get a broken manifold stud Roy and need to pull the turbo off we should do a quick swap, get shaun to give it a quick 1hr tune and see what it pulls. hahaha if only it was that easy. I still think your setup is awesome, not to forget RacePaces tuning

Sorry for the bodgy overlay. I thought it would be interestering to overlay Bl4ck32's RB30DET running a Rb20DET highflow and my Rb30DET running the stock rb20det turbo on stock boost. Bl4ck32 ran out of load points on the pfc for that run, I believe it was actually 15psi he was running. Since fixing that issue up he is now running 218rwkw on 16psi I believe. Its interestering to note how the bush t3/4 spools basically identical to the stock rb20det turbo once its on the larger 3ltr.

haha Thats bodgy as sh*t. Head down to supercheap or where ever and grab a nice new big fat earth wire. Thats one fixed.. Unsure what to do about the other one though. I replaced it with a 480cc Excide thing with a nice little window to see the condition of the battery. It spins the car over rather quick.