R32 + Rb25De+T Neo

[Sarumatix]

Started building an R32 gts-t with a blown RB20 with an R34 RB25de. Going to +t it by moving all the parts over from the dead RB20det. What turbo recommendations would you guys suggest?

Want a reliable power figure so was thinking around the 250rwkw mark with the possibility of using E85. I also want to minimise mucking around too much with the exhaust etc (rather stay 6 bolt if possible). I'm guessing this lands me in rebuilt R34 turbo territory?

ps. Would be nice if the the dyno thread has more charts than chats .

[dori34]

hypergear turbo would suit you best if wanting to stay IWG. unless you wanna go EWG then go a kando turbo.

basically have a look at the rb25det thread in the forced induction section and see what turbo setup they used, and you can get away with the same, if not more power & torque as you'll be using E85.

[N-DAWG]

Something with a large rear housing. DE+t's spool up very quickly, sometimes too quick IMO. That's based on a R33 Series 2 Compressor on a RB25DE NEO Motor. I found I revved out first gear before making the most of the boost.

I agree Hypergear would be a good way to go to keep the stock fitment. I was considering doing another DE+t with a hi flow hypergear, but in the end did a motor swap.

[Sarumatix]

Ah that's exactly what I was worried about N-DAWG. Making the same power as DETs with 30% less boost + E85 surely means I want something with a big exhaust housing. I was looking at the TR43 or whichever they are called and then I started drooling over GTX3071r's, then I decided it was all too difficult and started looking for RB25 turbos, now i'm back to square one .

[Count Grantleyish]

Dave, thought about slapping old school T03/04 hybrid?

If they're this laggy on normal 25det, surely it'd go nicely on 10.6:1 compression ratio motor.

[N-DAWG]

I saw a fair few tr43 hypergears going back when I was looking but majority were first gens.

Motor swap with my usual bolt ons with stock R34 turbo and my rebuilt shift kitted auto box just netted me a very responsive 215.3kw at rear wheels on 14 psi and approx 192 kW on 9psi. Maybe it's the profec e01 and emb running with map sensor but I'll take this over the na+t set up any day! Better mileage too as na+ t is pretty much always on boost.

[clip14]

i have completed the exact mod.

r34 rb25de+t in a r32.

I used a t04e, which is a old laggy turbo on a normal engine, but on the high compression motor, its not too bad.

run in tune is 200rwkw at 9psi.

I am getting the car re tuned in a few weeks with r34 GTT injectors (straight fit) and a z32 ecu (with a daughterboard, remapped, and re-pinned to suit an inline6) because the z32 ecu is the only ecu which will plug into the r32 loom and has vct control.

vct should bring on boost 500rpm sooner as well depending on the tune.

will let you know what the result of the final tune is. I'm shooting for something more responsive, and with additional power, the limiting factor are the injectors which will max out around 250kw.

[iseekool]

i have completed the exact mod.

r34 rb25de+t in a r32.

I used a t04e, which is a old laggy turbo on a normal engine, but on the high compression motor, its not too bad.

run in tune is 200rwkw at 9psi.

I am getting the car re tuned in a few weeks with r34 GTT injectors (straight fit) and a z32 ecu (with a daughterboard, remapped, and re-pinned to suit an inline6) because the z32 ecu is the only ecu which will plug into the r32 loom and has vct control.

vct should bring on boost 500rpm sooner as well depending on the tune.

will let you know what the result of the final tune is. I'm shooting for something more responsive, and with additional power, the limiting factor are the injectors which will max out around 250kw.

Are you running the stock DE injectors (270cc) at the moment?

Reason I ask is because I'm thinking of going a similar route - I'm not going after big gains, but lots of low down power and a fat torque curve, high compression + turbo, like euro cars such as VW GTI, XR5 turbo and Audi turbo.

I'm thinking to keep it simple - stock GTt ehxaust manifold and piping + ecu remap. I want to run low boost ~6 to 7psi

I like the thought of having max torque from around 2000rpm

http://www.webwombat.com.au/motoring/news_reports/ford-focus-xr5-turbo.htm

[Sarumatix]

Have been advised that injectors are pretty much a must.. and coming from an Rb20, 270cc injectors don't go far .

7 psi isn't actually low boost, that's factory R34 boost so you could just use the whole setup and get that boost without any mucking around.

The NA motor has smaller intake manifold and twin runners after the throttle body so you will need to do some custom work to get the R34 piping to mate up (cross over pipe can't be used).

The block will still need to be tapped for the appropriate oil return which might be difficult without pulling the engine out (no idea, my engine is on a stand so that's easy ).

[dori34]

on the neo blocks, theres a blanking bolt underneath the powersteering pump/aircon pump which you can use, no need to drill/tap into the block.

for the oil feed, you can get a T junction from near the oil filter and get it from there.

people have used the standard RB25DET cross over pipe but slightly modded to run on the rb25 neo twin intake plenum.

[clip14]

the 270cc standard injectors held up to 200rwkw with a safe a/f ratio on the dyno. but the tune was accomplished with a chipped ecu and an increase in fuel pressure (only about 10psi). with 6 cyl engines, usually the cc rating of the injectors represent the supported horsepower, so 270cc injectors will max out with 270 hp, or just over 200kw. bump the fuel pressure a bit and you can make 200rwkw with some injector duty to spare.

just be aware that walbro pumps dont like going overpressure by more than 10psi, if you want to use overpressure on your fuel pump to acheive higher injector flow, i recommend a bosch 044 or similar. even better would be the GTT injectors which are straight fit and will hold 240+. GTR injectors require resistor packs and a custom fuel rail.

6-7psi on a standard GTT turbo should put you around 180-200kw and excellent response. factory injectors will hold with a good tune.

remember that with increased compression (over 10:1) that 6-7psi may net you more than expected figures, and you may run into some fueling issues. no doubt on the spool time though, especially if you retain vct, and have a decent tune.

[iseekool]

the 270cc standard injectors held up to 200rwkw with a safe a/f ratio on the dyno. but the tune was accomplished with a chipped ecu and an increase in fuel pressure (only about 10psi). with 6 cyl engines, usually the cc rating of the injectors represent the supported horsepower, so 270cc injectors will max out with 270 hp, or just over 200kw. bump the fuel pressure a bit and you can make 200rwkw with some injector duty to spare.

just be aware that walbro pumps dont like going overpressure by more than 10psi, if you want to use overpressure on your fuel pump to acheive higher injector flow, i recommend a bosch 044 or similar. even better would be the GTT injectors which are straight fit and will hold 240+. GTR injectors require resistor packs and a custom fuel rail.

6-7psi on a standard GTT turbo should put you around 180-200kw and excellent response. factory injectors will hold with a good tune.

remember that with increased compression (over 10:1) that 6-7psi may net you more than expected figures, and you may run into some fueling issues. no doubt on the spool time though, especially if you retain vct, and have a decent tune.

Thanks for the info. Very informative.

I was actually thinking/aiming more conservative. Around ~150rwkw

The car is used mainly for long distance driving (road trips) highway runs and through the twisites.

My main reasons.

- I'm on a budget

- Less complexities - so I can convert it back to an n/a easily (if i so desire)

- My car is an auto, so I'm not too keen with putting too much power through the stock trans.

- I plan on retaining VCT functionality

- I have no intention (unless I really have to) of upgrading to big brake kits or beefing up the driveline.

I got a few more questions regarding my "proposed" setup.

- With my lower power requirements - does this mean I just get my current stock N/A ECU remapped *or* must I go for a remapped GTT manual ECU (due to running an auto)?

- Will my AFM need changing?

- Does this mean I can run lower boost? (ie. no need to run 6~7psi, can I get away with running 4~5psi?)

- Will the stock GTT SMIC be enough or will I need to get an FMIC?

- Will a stock GTT turbo be too big?

[Sarumatix]

This project is progressing well. To the point that I'm going to start up a build-up thread. Ended up with a high mount T67 with 45mm external gate so a little bit more extreme than what I started with. oops. Entertaining until I realised that with the turbo up there, now the de throttle body just about hits the turbo.. time for some chopping.

I'm trying to find out if the valve springs in an R34 RB25de are the same as the det? given i'm looking at changing the camshaft because of the shitty lift on the exhaust side, do I just go stupid and do the valve springs at the same time? Kinda didn't want to crack the motor :S.

[Sarumatix]

I got a few more questions regarding my "proposed" setup.

- With my lower power requirements - does this mean I just get my current stock N/A ECU remapped *or* must I go for a remapped GTT manual ECU (due to running an auto)?

Can't remap the stock R34 ECU last time I checked due to the 16bit architecture, to my knowledge nistune is only available on old 8bit ECUs (R32, Z32, S13). You can use a nistuned Z32 ecu with some changes to the loom (At the ecu plug) or by repinning as Clip14 mentioned. How this goes with your auto is anyones guess (and one of the reasons why my gearbox is in the bin and a manual R33 is sitting on the hoist ). Most people don't fark around with autos and I gave up on the idea of playing with the auto because of the lack of information. My best guess is that, if you don't have the tiptronic, then a z32 auto ecu will talk to the auto ecu. I could be wrong and it does, or I could be wrong and it doesnt' talk to any other auto boxes . Good luck?

- Will my AFM need changing?

No, not with your power goal.

- Does this mean I can run lower boost? (ie. no need to run 6~7psi, can I get away with running 4~5psi?)

6-7psi is safe and will not push any of the de hardware outside comfortable operation assuming you have the fuel map tuned properly. The hardware becomes problematic when you go above 7psi. (The stock RB25de neo injectors are to the best of my knowledge 290cc).

- Will the stock GTT SMIC be enough or will I need to get an FMIC?

You want a FMIC in Australia for all applications, the SMIC is never sufficient. I'm sure people will argue about this but my view is that if you have to mount up an intercooler, you are are best of spending that time and money on something that is going to keep your charge air (and hence your potential for detonation) to an absolute minimum.

- Will a stock GTT turbo be too big?

My answer is No, however I have heard lots of different interpretations on this subject. The engine you have is designed to make power without any turbo so it has high compression and is set with cams to make power early. The high compression means you want low boost. The cam lift on the exhaust side is pitiful (http://www.tomei-p.c...haft-specs.html) and has been known to result in up to 1000rpm of turbo lag on its own (on boost after 4000rpm). With the stock setup I would guess that a R34 turbo is about as big as you can go without getting serious (E85, cams, External Gate... etc).

On the other hand, because the R34s compression can get the turbo up sooner, it can also result in extra exhaust gas at the top pushing the limits of the little internal gate. You might consider going for something with a big internal gate just to minimise this effect. I haven't seen enough dynos of RB25DE+T neo setups to be confident that the R34 stock turbo wont do the job perfectly for you. Let us know .

and then on the other hand, perhaps if you just swapped out the exhaust cam to get some lift and even fiddled with the durations this would cure all of the problems, this is certainly going to put a hole in your budget.

I guess you have to remember you are forging into the unknown a little, the RB25de neo is different in a few key ways to all the other RB25s out there and is a great starting point for making power, but a lot of the basic rules of the other engines just doesn't apply in this case. As I mentioned above, even just a high mount turbo kit while fixing some problems, ends up creating others .

Feel free to ask more questions, Saru

Edited February 8, 2013 by Sarumatix

[ff_driftz]

hi guys,

I have read some threads about the +t for a neo, can any one tell me if the pistons rod and cranck are the same on the de and det? and also can a de make safe 300rwkw? with a td06 20G (khando?)