Harey

Except for dodgy boost signal and you running 25psi when it was tuned to less than 20psi?? The better the turbo the worse damage you will do from running way above tuned boost levels!

garrett or hks turbo wont stop you f*%king up the install... rb25/30 setup and dynoed before xmas???????

I have seen numerous rb25/30 setups with a 3076 that do not drop off power up top, therefore by your reasoning they are not 'choking'. There is one on here that is making 320rwkw with crazy response (Als I think). I do not see many rb25s with a 3076 making 320rwkw (I know it is possible) so the turbo is making more peak power then on a smaller motor so thats also saying that its not choking by your last sentence. You could argue that an SS1 or HKS GTRS is also 'choking' on an rb25 in that it might drop 10-20hp by 7000rpm but people love those due to the response and power/torque at street legal speeds.

Depends what your definition is of choke. SS2 has made 300rwkw on 98 fuel with full boost at 3800rpm. To me that sounds very similar to a GT3076 and they run very well on rb25/30s. Sure a bigger turbo would run well too but this will have excellent response.

Not a chance! SS2 FTW!

I was running 275/35s on my 9.5" wheels. I think the 395/30 is a typo haha. I would use either 295/35/18 or 315/30/18. I have 265/35/18 Federal RSR Tyres on now and love em, now just hoping they last a while, other reports say they will.

Bugger it may as well go an rb30...

Great result from the customisations to the SS1PU. Loving the ~500Nm of torque from 3700-5500rpm. Looking very similar to joeyjoeys results with a HKS 2835 Pro S on the exact same dyno!

As above: - stock bov is awesome, if you want a bit more turbo noise put a pod filter on and you will hear some woosh and some pshhh. If you dont want the noise just get a good panel filter in the standard airbox. - stock intercooler will go to 200rwkw fine but yeah a bigger front mount is better. Just make sure its return flow and black for the po po. - Strongly suggest nistune over power fc on an R34. - Dont worry about a turbo timer. - Is the short shifter to make the shifter feel nicer or for speed. If its to feel nicer sure but dont worry about it if you are doing it to be faster.

Yeah as said the difference between 27psi and 45psi relative fuel pressure is a lot and definitely something I would expect to cause it to run lean. Hopefully it was brief enough to not cause any damage! As far as a cause for it, yeah just old or crappy vacuum lines. Definitely replace them, I really like the Turbosmart range of vacuum hose as its nice and soft and seems to hold on really well. Also make sure there is enough length in the hose so that when the engine twists/moves that its not putting too much tension on the hose. Is there already a clamp on that vacuum hose? If not get one.

Very Impressive!!

http://www.ripsltd.com/products.html RB30 stock internal long engine (block crank, pistons, rods, oil pump, GTR head gasket, Complete R33 RB25 head, new water pump, cam belt, idler and tensioner bearings) fully refreshed with crack tested, straight tested, cleaned, polished and grub screwed crank, ACL race bearings, mint stock oil pump, acid dipped block with oil restrictors, power honed, decked, new high quality rings, new brass frost plugs, refreshed stock head with new seals etc, all assembled and painted (suit 600hp and 7000rpm) nzd5000 for 2wd or nzd6000 for 4wd with adapter plate and pickup.

Yeah I went the 5" as well. I reckon the 4.5" will be fine though.

That sucks about the aftermarket plenums, surely there must be one of them that doesnt loose power/torque. Heaps of crazy cars run them. I havent looked into them as I am trying to stay stock looking. Strange I have a 90 deg bend intake pipe with the standard intercooler piping.

Ah that sucks with the intercooler piping. Do you have an aftermarket plenum? If your going to redo all the piping I would look into that so you dont have the piping crossing over the engine. Your going a big turbo with an external gate so you may as well go the whole hog now I would go 3" intercooler piping especially after the cooler and put the afm in there. Exhaust sounds good as long as the catback is 3" straight through the whole way. If you just have a pod the intake pipe is just a 90 deg bend isnt it? Mine has 2 return fittings from the bov and pcv.

How would you like him to develop, punch it into a magical calculator and produce the perfect turbo first time? No better test than in practice. Theory is great as it can guide you down the path but at the end of the day you need to verify it actually does what the theory suggests. Stao has a great turbo understanding and if he has one weakness its constantly trying to improve his turbos even when he makes something that is a great turbo. He also researches how other turbo manufacturers get their results. Getting result X, identifying the weaknesses and using theory to try and improve them and repeating the practical test to see if it did is an excellent approach. Turbos are not a simple thing and I bet the other turbo manufacturers do the same thing but they just keep it behind closed doors whereas Stao is generous enough to show us. I much prefer reading this thread instead of Garrett released this new turbo and it made X power.

+1 very interested to see how you go Hanaldo! What do you mean by redoing all the piping? You cant mean intercooler piping cause you said 4". You must mean the intake piping. So are you putting a reducer on the front of the turbo down to 3" straight away so you can run your current intake pipe correct? Do you have the intake pipe hooked up to your factory airbox? If so, yeah I can understand how that could be tricky to redo. Will you eventually be cutting a 4" hole in the bottom of the airbox and joining to 4" piping? With the afm located in the cooler piping. I would be very tempted to do this straight away to save having to get it retuned again later anyway. Not to mention with a large turbo such as this I would want to give it as much air as possible. This can improve response and top end! What exhaust do you have? I have read so many threads where people put large turbos on without spending a lot of time on intake and exhaust and they get average peak power figures but with a lot of lag. Either way will be watching closely

Thanks for all your help but I havent actually read what you said Stao is in Melbourne. "I Used Reflex engineering for engine rebore, short block building and head reconditioning: 93054807 AMR work shop for assembly: 93866196" Zebra also said Racepace have a very good reputation in melbourne but it wont be cheap. There are plenty of workshops in melbourne that will do the work but I would say most would have mixed feedback depending on who you spoke to.

Why the super low boost level and rev limiter?? Are you running the engine in?

I know what your saying but if the torque is falling away that much with such a large turbo then surely something is restricting things. Would be worth pumping up the boost to see if it overcomes the issue or it gets worse as a test.

Now you are taking engine advice from your wife haha Tell her how long your car will be off the road for compared to putting in another standard engine. You sure like to stir "your engine couldnt handle 250kw". No you couldnt handle the modifications and were running more boost than was tuned for, plus you were changing boost hoses and other things. So many stories of rebuilt engines having issues, nissan seem to do a good job. Standard headgaskets are running well in 1000hp cars so I think your 250kw should be ok

Hence the advice to throw in another stock engine. If your mr home mechanic then you could have a go at replacing it yourself. Cars are generally not the thing to just try yourself and learn from your mistakes because they are so costly. At least have someone knowledgeable check it over or give you advice in the first place.

Your a strange feller lilcrash. From all the issues you have resolved you are obviously capable with a reasonable level of mechanical work. The strange thing is the bizarre conclusions you come to and wont listen to other peoples advice when its very common stuff. Yep a rebuild or throw another stock engine in. The fact that the engine was fine with the standard turbo means sometime since the new turbo was fitted you have been running lean or with too much timing for one reason or another. Its important to get things setup correctly before getting a tune so the tune can be helpful. If you change things after a tune, the tune is out and can no longer be assumed safe (depending on whats changed). With enough fuel and a good tune, the engines are really strong so my advice would be a replacement standard one especially after reading about all the rebuild failures on here.

Go the 740cc injectors so you have the option of E85 in the future

Quite a lot of boost drop. Very impressive numbers though. I have seen the poncams net some pretty nice gains (Matt from Nistune's result).