Jump to content
SAU Community

Recommended Posts

Im just about to put a rb25det in my 32 coupe and i have the choice of the standard turbo or a vg30 highflowed turbo. I know next to nothing when it comes to turbos so I was just wondering what the better option would be and what each one would offer / the differences between the two.

If its of any help in making a choice i will be running a turbo back 3" exhaust, front mount, yellow jacket coilpacks and standard ecu. Probly not looking to boost over say 14psi as its mainly for street use and i will drive it as a daily pretty much.

Thanks in advance,

Matt.

Link to comment
https://www.sau.com.au/forums/topic/401497-which-turbo-for-rb25det/
Share on other sites

quickly before anyone gets in here, have you tried doing a serch on the vg30 turbo (either on here or on Google), the standard turbos performance is well documented in here and I'm sure you'll find a rough figure for the vg if you search around...

Those are pretty hard to come by these days, they have been discontinued haven't they?

well they are around just fewer, and they arnt the same low price/performance as a HG or VG30 highflow, but if the OP wanted real info it could just do a search...

standard ecu and turbo upgrade, I rest my case

For f**k's sake. The RB20 ECU wil not even blink if you put a VG30 turbo on there. The car will just go faster.

The way you guys carry on anyone would think you have to retune your ECU when you change you bloody spark plugs. There have been about a bazzilion R32s with VG30 turbos slapped on them that have run perfectly well and made the same power on about 10 psi of boost as they do on 13+ on the original turbo. And the mixtures are fine, and the engine doesn't ping itself to death.

To the OP. You won't likely be able to run 14psi with a VG turbo because your standard fuel system won't be up to the task. If you do not have a bigger fuel pump than the original then you shouldn't really even turn the boost up on the standard turbo, because the old original fuel pump is probably only days away from dying anyway, and will drop pressure at the top end of the flow curve. If you put a bigger pump in then at least you will keep full fuel pressure and your standard injectors will run out of flow where everyone says they do, not 25rwkW earlier. But they will still probably run out well before you get a VG30 turbo to 14 psi.

Yellow jacket coils are shit. Expect them to fail.

Choose the VG turbo. Run it at standard boost and don't wind it up unless on a dyno or at least with a wideband on it on the road. It will be good.

Any turbos is just a combination of wheels and housings, just the right on size for the job. .63 VG30 turbine is a good high flow base. Final out come depending on what the final goal is, car's setup as well as budget. I did a OP6 high flow (running same A/R turbine as vg30) using customized billet CHRA last year, made 293rwkws with full boost by 3400rpms on pump 98.

http://www.digi-hard...90911/power.jpg

http://www.digi-hard...0911/booost.jpg

Get a proper ECU if you are doing powered up mods. Other wise just bolton a R34 or VG30 turbo and leave it on 12psi of boost.

For f**k's sake. The RB20 ECU wil not even blink if you put a VG30 turbo on there. The car will just go faster.

The way you guys carry on anyone would think you have to retune your ECU when you change you bloody spark plugs.

Read the post again,

i have the choice of the standard turbo or a vg30 highflowed turbo.

The OP is more than welcome to run a highflowed turbo on the stock ECU. Sure it will probably be ok (although we have no idea who hiflowed it).

I would run the stocker with those mods, you might go the other way...it hardly requires getting your knickers in a knot.

Mate , first thing is to know where you are going with this, i started out with a highflow but you may soon get bored with that and wish you had more then wish you had just got a proper garrett turbo to take car of business, dont do things twice its too expensive....either do half measure with stock computer or go all the way and spend $$$$

my advice is get a highflow and be happy with say 220kw.. or go all way with a gt3076 or hypergear and go 280-300kw and know you have a real beast.....

For f**k's sake. The RB20 ECU wil not even blink if you put a VG30 turbo on there. The car will just go faster.

Who said anything about a rb20 ecu???

I would think if he's converting to a rb25det the smart thing to do would be to use a rb25det ecu, which will freak out even with increased pressure on a std turbo

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

    • Update 3: Hi all It's been a while. Quite a lot of things happened in the meantime, among other things the car is (almost) back together and ready to be started again. Things that I fixed or changed: Full turbo removal, fitting back the OEM turbo oil hardlines. Had to do quite a bit of research and parts shopping to get every last piece that I need and make it work with the GT2860 turbos, but it does work and is not hard to do. Proves that the previous owner(s) just did not want to. While I was there I set the preload for the wastegates to 0,9bar to hopefully make it easier for the tuner to hit the 370hp I need for the legal inspections that will follow later on. Boost can always go up if necessary. Fitted a AN10 line from the catch can to the intake hose to make the catchcan and hopefully the cam covers a slight vacuum to have less restrictive oil returns from the head and not have mud build up as harshly in the lines and catch can. Removed the entire front interior just shy of the dashboard itself to clean up some of the absolutely horrendous wiring, (hopefully) fix the bumpy tacho and put in LED bulbs while I was there. Also put in bulbs where there was none before, like the airbag one. I also used that chance to remove the LED rpm gauge on the steering column, which was also wired in absolute horror show fashion. Moved the 4in1 Prosport gauge from sitting in front of the OEM oil pressure gauge to the center console vents, I used a 3D printed vent piece to hold that gauge there. The HKB steering wheel boss was likely on incorrectly as I sometimes noticed the indicator reset being uneven for left vs. right. In the meantime also installed an airbag delete resistor, as one should. Installed Cube Speed premium short shifter. Feels pretty nice, hope it'll work great too when I actually get to drive. Also put on a fancy Dragon Ball shift knob, cause why not. My buddy was kind enough to weld the rust hole in the back, it was basically rusted through in the lowermost corner of the passenger side trunk area where the wheel arch, trunk panel and rear quarter all meet. Obviously there is still a lot of crustiness in various areas but as long as it's not rusted out I'll just treat and isolate the corrosion and pretend it's not there. Also had to put down a new ground wire for the rear subframe as the original one was BARELY there. Probably a bit controversial depending on who you ask about this... but I ended up just covering the crack in the side of the engine block, the one above the oil feed, with JB Weld. I used a generous amount and roughed up the whole area with a Dremel before, so I hope this will hold the coolant where it should be for the foreseeable future. Did a cam cover gasket job as the half moons were a bit leaky, and there too one could see the people who worked on this car before me were absolute tools. The same half moons were probably used like 3 times without even cleaning the old RTV off. Dremeled out the inside of the flange where the turbine housing mates onto the exhaust manifolds so the diameter matches, as the OEM exhaust manifolds are even narrower than the turbine housings as we all know. Even if this doesn't do much, I had them out anyways, so can't harm. Ideally one would port-match both the turbo and the manifold to the gasket size but I really didn't feel up to disassembling the turbine housings. Wrapped turbo outlet dumps in heat wrap band. Will do the frontpipe again as well as now the oil leak which promted me to tear apart half the engine in the first place is hopefully fixed. Fitted an ATI super damper to get rid of the worn old harmonic balancer. Surely one of the easiest and most worth to do mods. But torquing that ARP bolt to spec was a bitch without being able to lock the flywheel. Did some minor adjustments in the ECU tables to change some things I didn't like, like the launch control that was ALWAYS active. Treated rusty spots and surface corrosion on places I could get to and on many spots under the car, not pretty or ideal but good enough for now. Removed the N1 rear spats and the carbon surrounding for the tailpipe to put them back on with new adhesive as the old one was lifting in many spots, not pretty. Took out the passenger rear lamp housing... what do you know. Amateur work screwed me again here as they were glued in hard and removing it took a lot of force, so I broke one of the housing bolts off. And when removing the adhesive from the chassis the paint came right off too. Thankfully all the damaged area won't be visible later, but whoever did the very limited bodywork on this car needs to have their limbs chopped off piece by piece.   Quite a list if I do say so myself, but a lot of time was spent just discovering new shit that is wrong with the car and finding a solution or parts to fix it. My last problem that I now have the headache of dealing with is that the exhaust studs on the turbo outlets are M10x1.25 threaded, but the previous owner already put on regular M10 nuts so the threads are... weird. I only found this out the hard way. So now I will just try if I can in any way fit the front pipe regardless, if not I'll have to redo the studs with the turbos installed. Lesson learned for the future: Redo ALL studs you put your hands on, especially if they are old and the previous owners were inept maniacs. Thanks for reading if you did, will update when the engine runs again. Hope nothing breaks or leaks and I can do a test drive.
    • No those pads are DBA too  but they have colors too. I look at the and imo the green "street" are the best.
    • I’m not sure what happened I told them about sonic tunes free OTS tune and the next the I know .. I was booted..   To funny 
    • Yea - I mean I've seen my fuel pump which is decades old and uh, while I'm not saying this with real knowledge... but I sure get the ick at using anything in the fuel system that produced the state of that pump. Many years ago I went through multiple pumps (and strainers) before I dropped the tank to clean it out with extreme violence. I'm talking the car would do maybe 50km before coming to a halt, which resulted in me cleaning out the filter with some brake cleaner and going on my way. None of my stuff ever looked like what came out of your fuel tank. I don't think I'd be happy with it unless every single component was replaced (or at least checked/cleaned/confirmed to be clean here).
    • I'm not going to recommend an EBC pad. I don't like them. Just about anything else would suit me better. I've been using Intima pads for a while now.
×
×
  • Create New...