Jump to content
SAU Community

Recommended Posts

Well....

I brought my r33 rb25det with this insanely big turbo already on the car....looks like a gt35 front but the exhaust housing of it is huge and when i would drive the car it would lag and in first gear kick in at about 6k revs, and 2nd like 5500, but when it kicked in it would sit me back in my seat on stock 7psi,

BUT i recently brought a new DSR 430 turbo, and then raised the boost up to 10psi, it spools up at about 3k and i get full boost by about 4-4500revs

But even though i raised the boost and its hitting boost for longer in the rev range....its actually going slower then the old turbo. The old big turbo i had i would be doing about 60 before changing into 2nd and about 100 at the end of 2nd, and it was on stock 7psi but with this dsr turbo i get to about 50kph in 1st and about 90 in 2nd gear... on 10psi

The DSR turbo keeps power through all the way to redline aswell,

So is this becuase the DSR430 turbo i brought a piece of chinese crap? or do i need a really decent tune? or a high quality turbo such as a garretgt30 or somthing?

Thanks guys!

Link to comment
https://www.sau.com.au/forums/topic/306036-too-big-turbo-vs-normal-turbo/
Share on other sites

you need both, the turbo sounds like ass and the tune probably hasn't been redone since you changed the turbo

Iv brought a power fc, and I have a bosch pump, going to get my injectors high flowed and have a z32 afm lying around, and my hks evc so looking to get it all put in and dyno tuned

But i dont want to have to go back wanting more power, so am wondering what would produce more power...tuned turbo i have now or the big one put back on, because i cant really afford to buy another turbo.... but i might have to i guess :worship:

You are running all of that on a stock ECU?

If so - thread ends. Until you get a decent tune into the setup it's impossible to say what could be wrong/better/worse due to the factory ECU having a fit.

Fark, so it was running a GT35 with probably a 1.06 exhaust housing on a stock ecu, stock injectors and stock AFM?!?!

Yep...guy i brought it off had it on with stock ecu and stock everything apart from fuel pressure reg and intercooler.... i know i need a tune but would want to sus out my turbos before i get the power fc i just brought tuned in...

And would that turbo run any good after the tune with new injectors fuel pump and a z32 etc?

Car seems to run fine so im hoping not much damage was done.... :D

Well that turbo will make a hell of a lot more power than the standard RB25 bottom end could ever handle and the rear housing will make it laggy as hell. So yes it would run after a tune, but personally thats a bad turbo choice for what you want. So i would rip it off and sell it, or atleast get the .86 housing for it.

Please stop saying "Brought" Its bought.

Sell the turbo, get a highflowed stock one. You will need an ECU (Your PFC). Your injectors will be ok for the power output of the highflowed turbo. You will need a decent fuel pump too.

To get efficient power out of the one you have now, it will cost you thousands.

Well iv still got the DSR430 turbo with a .63 exhaust housing... they claim 250kw on a standard rb25 at 1bar with only being tuned http://www.sella.co.nz/motoring/car-parts-...ssories/575cb2/

So might aswell just stick with this and wait to see how the tune comes out?

Oh and how much power can stock injectors handle? was thinking i could get them high flowed but if i dont need to i would like to save the money...

if you have a gt35 wouldnt it be high mounted aswell?

so if you put this other new turbo on you will also need to go back to low mount set up. which means buying manifolds and other bits.

in my opinion u should just buy the smaller ex.housing. i had a gt35 on my 33 gtst with the 0.82 and honestly its not as bad as people make them out to be

^ and that's the problem sometimes.

What one person calls laggy and unresponsive, another person says its not too bad.

Could be they have not been in a better setup, could be they are happy with how theirs is.

Whatever the reason, you need to be open to the idea that there can be better out there at some point.

^ and that's the problem sometimes.

What one person calls laggy and unresponsive, another person says its not too bad.

Could be they have not been in a better setup, could be they are happy with how theirs is.

Whatever the reason, you need to be open to the idea that there can be better out there at some point.

i agree with what you have said above, everyone has there own opinions on what lag is. my opinion is based on going from a standard turbo to a hi flow and then to the gt35. i was of the opinion that it would be laggy before i bought the set up but was advised to for a drive in 1 with a gt35 set up and i was very happy with how it went so decided yeh ill do this for mine aswell. couldnt of been happier with how it turned out.

for the OP, just abit of info with my set up, we pulled 290kw atw on a standard engine with 550cc injectors, walbro fuel pump, PFC and just the usual stuff like exhaust and intercooler.

the engine was still in perfect shape aswell.

i agree with what you have said above, everyone has there own opinions on what lag is. my opinion is based on going from a standard turbo to a hi flow and then to the gt35. i was of the opinion that it would be laggy before i bought the set up but was advised to for a drive in 1 with a gt35 set up and i was very happy with how it went so decided yeh ill do this for mine aswell. couldnt of been happier with how it turned out.

for the OP, just abit of info with my set up, we pulled 290kw atw on a standard engine with 550cc injectors, walbro fuel pump, PFC and just the usual stuff like exhaust and intercooler.

the engine was still in perfect shape aswell.

wow 290atw? how much boost was he running? oh and was that with the .82 housing? when would that kick in about?

Well im happy to deal with the lag...it was bad but i want to get alot of power with what iv already got....and that turbo had it even untuned, as im unhappy with the turbo i have now...but im just unsure... if i did put that big turbo back on and had the same mods as uwissh said...or if a decent tune with the smaller turbo i have now as to which would be better power wise

But the smaller turbo im using now is more driveable seeming im not skidding out in every gear like the other turbo :D

Edited by R33 0wnerrr

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Actually, that's not entirely true. It's also the same motor in the 1st gen Nissan Cube but they're rare as hen's teeth.  
    • Yeah it is always worth testing and balancing actuators out of the box, just set the pressure regulator on a compressor very low (eg 5 psi) and increase it slowly to see when they both move.....unfortunately while you may be able to adjust the length of the actuator rod to minimise any difference, the actual pressure they move from is not adjustable so you need a well matched pair. And yes, the VCAM is probably contributing; the earlier in the rev range they come on boost and the slower the revs build (I think your demo was in 5th), the more you notice it.  Driving at WOT through 1st, 2nd, 3rd etc you will probably never hear it as any shuffling starts and is over super quickly
    • oh they were with that motor, you need to remove the engine to change the spark plugs (don't have to, but it does make it easier)
    • I certainly fall into the annoyed camp, but glad to hear that if it's happening at low boost then I'm not likely going to blow a turbo and end up with metal shards in my oil. Just feels like it prevents me from really driving it without hesitation and "peak" performance. Wonder if it's the VCAM, it did an impressive job of shifting the torque curve and faster spool, but maybe now it's "too fast" and there's too much air for how open the throttle is.  Based on some other threads, will also do some reading on synchronizing the actuators. They are the default actuators that come on the Garrett's and I would think they would be set the same coming from the factory, but if the turbos don't actually work exactly the same way at the same time as previously mentioned, it would be worth making sure the actuators are actuating together properly
    • I went down this rabbit hole before, ended up sourcing a motor from the UK (I'm in Japan) which also didn't function correctly. With the original motor, I disassembled it and reassembled it and it works somewhat, sometimes. What I could deduce from all my screwing around is that there is calibration of the gears on the inside of the motor and two ramps on the main gear which activate switches that operate the motor and move the sunroof either to retract into the roof or tilt. Where I got stuck was that, it seemed in my case that one or both of the switches that are activated by the ramp on the gear did not always activate and thus the motor did not move, causing it to sometimes not retract or tilt (apologies, I've forgotten which way it didn't work.).  Of course this part is discontinued at Nissan now, it's the same part in the S15 but no other models. I also contacted the manufacturer of the component for schematics - forgot the name, they're based in Gifu - but they declined to share the information due to being bound by an NDA, sadly. Looking through my pictures now, it seems I last had a crack at this in 2022. See, I so kindly wrote "open" and "close" next to the switches. If you figure it out, please do tell me. Those little switches, with the red buttons may need to be replaced.
×
×
  • Create New...