Jump to content
SAU Community

Recommended Posts

Hey all,

I have a 2001 R34 GT-T that I recently modified with the following..

HKS GT-RS
Z32 AFM
Deatchwerks 600cc Injec.
APEXI Power FC
Apexi panel Filter
Bosch040 Fuel Pump
Blitz SE Intercooler
Splitfire Coil Packs
Exedy sports Clutch
HKS EVC 6 Boost Controller
NGK Plat. Plugs
The help I'm chasing is where to go from here? I made 250rwkw on pump 98, however I was hoping for a little more. I've been researching thoroughly however I'm currently at a bit of a loss.
The car is extremely responsive and that's what I was going for when planning these upgrades, I don't want to lose that..
I'm looking into type B pon cams, and it's my understanding, with the turbo selection I'm right on the boarder of type A vs type B..
Also looking into e85, however I know this will require fuel system upgrades..
Can anyone recommend anything else I'm missing?
I've seen a few 33gts-t's on this forum supposedly making 300kw with this turbo and was hoping to get closer to that..
Any suggestions are welcome,
Cheers.
Link to comment
https://www.sau.com.au/forums/topic/439882-r34-gt-t-mods-and-the-future/
Share on other sites

The GT-RS is a good street turbo. Gives great response but chokes the engine up top. Remember that dynos vary, so 250 on yours might be closer to 270 on another, and 270 on that one might be closer to 300 on another. So you can't compare unless you can do a backup check like same dyno same day or trap speeds.

If you want more power you really need to look elsewhere. Some of the HG highflows or new turbos would probably suit and then there are a handful of other options that make sense at varying budgets (such as HTAs or their replacements).

E85 will certainly get you another 30 rwkW or so, possibly more. Also help with the GT-RS being a bit of a hot gas restrictor for the engine too.

Cams will probably fall short on bang for buck, but E85 will net you a tiny bit more.

The thing is that 250kw is fairly close to the turbos outright flow potential on the turbine side. So going E85 MIGHT result in 20-30kw but most likely not more than that.

Be it myself I would accept that the setup is performing really well as it is and just enjoy it. The $$ outlay on going flex fuel wouldn't be worth the power gains and the hassle of running to E85 pumps just doesn't do it for me.

Cams wont do any good if the turbo is running out of puff. Many many moons ago I had a GCG highflow with 260 degree Poncams and the damn thing made 250 rwkw from about 6500 to 8000 rpm, so they helped fatten the top end.

But the turbo wouldn't flow any more than it would flow.

Bigger turbo for more power my friend.

it depends if you want to put up with travelling to buy e85 and if it's easy to obtain in your area basically. What boost level are you running? i'm willing to bet you can run a few more pounds on e85 to help chase power.

with the bigger top end it will be like having a bigger turbo without the added lag. it just comes down to how much of a hassle it is for you to run the fuel. If you already have all the other mods, then just a fuel pump and bigger injectors and a tune will get you there.

i went e85 a while ago and its awesome

250rwkw = good result on 98 ron

E85 won't need a total fuel system upgrade just a decent E85 safe fuel pump would be all I would do.

300rwkw was done on one of the dynos in Adelaide from memory......but I have a feeling it would make 250rwkw on the same dyno you used.

Thanks everyone,

I'm running 20pound quite comfortably, we had it up to about 23 but the knock levels were through the roof..

@wolverine, yea not an entire fuel system but I can imagine the 600cc injectors wouldn't be sufficient.. Fuel pump either for that matter.

I'm in the middle of moving to Brisbane and not too sure what E85 is available up that way but it shouldn't be too hard to find out..

30kw extra is nothing to sneeze at, if the fuel is readily available then why not..

Cheers for the responses!

Time for a new turbo if you're after more power.

Can't go past the hypergear line up for RBs.

I'm not sure what E85 availability is like in Brisbane. If it's a bit suspect, perhaps WMI might be a better option?

From what I understand 250rwkw from a GTRS is a healthy result - the OP cant expect much more. He might gain 20 odd kw with ethanol, but that's a $1000+ investment for a relatively small gain. Bang for buck I doubt he can do better than a bigger turbo at this stage (which is $2k+ but would net much bigger gains and provide much bigger overheads if he does go E85 or WMI later). If he's hell bent on keeping the GTRS, then perhaps WMI might be an option instead of E85, as he's identified a concern regarding E85 supply.

I was merely giving a couple of options. I don't see why you're so confused.

I'm not confused. Now that you have explained it more it makes more sense. Your initial post said if he wants more power he needs a bigger turbo, which as yiu agree isnt the case. Its just a case of value for money and time at this point.

I made 250kw on my old Sierra s1 highflow, and over 300 swapping to ethanol. There should be another 40-50kw in the GTRS if the tune is pushed, and with the amount of second hand injectors floating about he could probably convert for bugger all.

Saying that, I sell Walbro 255's for $100, or VDO pumps are even cheaper at around $70. Both should get there flow wise. You can get Siemens injectors pretty cheap these days... The main cost is in the tune, but that is inevitable when chasing power.

A larger turbo is not going to feel as good on the street and is going to cost heaps more.

600 CC would probably be a bit small to keep decent AFR's on your set up. I've got 1000cc and use 80% duty at 306kw 20psi on a HG highflow. that was with wheelspin from 5k+ RPM so we don't really know how much power is being made. anyway I think they are probably similarly sized turbos and 600CC injectors might only get you there with an adjustable FPR and a very good fuel pump

600 CC would probably be a bit small to keep decent AFR's on your set up. I've got 1000cc and use 80% duty at 306kw 20psi on a HG highflow. that was with wheelspin from 5k+ RPM so we don't really know how much power is being made. anyway I think they are probably similarly sized turbos and 600CC injectors might only get you there with an adjustable FPR and a very good fuel pump

!! I make 314AWKW with 550 Deatschwerks injectors. 600s will be fine.

!! I make 314AWKW with 550 Deatschwerks injectors. 600s will be fine.

On E85? 600s will be hard up against it. From what I've read here you need 20-30% more flow when running E85.

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

    • The average previous owner for these cars were basically S-chassis owners in the US. Teenagers or teenager-adjacent. I often tell people that neglect is easier to fix than something that was actively "repaired" by previous owners.
    • 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 
×
×
  • Create New...