How to turbo your N/A

[CDA]

fark i fully agree with andz, ya'll should save yourselves the hassle and the time and the uncertainty and sell your pride and joy and buy yourself a new and improved turboed pride and joy

[hugoboss]

Great Thread! My R33 GTST has a damaged engine (RB25DET). I’m considering purchasing a RB25DT engine & swapping the bits over as per this thread. I’m slightly nervous about the long term durability, considering the high k’s the vehicle does and the way in which it’s driven, however I’m interested due to the great price of a RB25DE engine!

The vehicle still has the standard ECU so the lower boost wouldn’t be an issue.

Question? Should I be paying some consideration to my Garret/HKS GT 25/35? As in, is this a too bigger Snail for this application? I suppose not as long as I’m using a decent tuning workshop right. (Racepace Melb). The only other mods are: larger intercooler, pod filter, 3in exhaust, spitfire coil packs & decent plugs.

180rwkw was achieved recently, however the engine had a damaged head/valve or valve guide seals or other. It still went really well, despite chewing through a heap of oil up until a piston went through the side of the block the other night! not good..

Thanks in advance for any tips.. HBOSS

[Domenico]

What if you were to add an aftermarket turbo kit to an R33 GTS or an R34 25GT?

'Caus thats what i wanna do

[1R34SON]

Geez dan after all these years this thread has been goin on, how much do you think you have spent to turborize ur car and all the stop and gos along the way? The slowness is starting to get to me but i love my car. Im thinking of selling it and getting a manual turbo? what does everyone think? worth the trouble converting or get a GTT?

[HTMR32]

hi,

i reckon if you put a det motor in it would be better at least it would have had a turbo run in to it, plus you can boost it more, instead of having a stock turbo on, it a de could maybe do damage cause of compression.

[1R34SON]

hi,

i reckon if you put a det motor in it would be better at least it would have had a turbo run in to it, plus you can boost it more, instead of having a stock turbo on, it a de could maybe do damage cause of compression.

hmm good point.

Anyone know much much price difference is for stock RB25DE motor? Its done 59,000kms very clean.. Compared to price of GTT motor? and where can I buy a gtt motor? wreckers n stuff ay?

[NA_Goodness]

Dont forget that the transmission, brakes, and diff are all different between the turbo and non-turbo. Just dropping in a turbo engine can put these parts under alot of stress. It is alot cheaper to buy a turbo car from the outset, but when you get paid like me ($6.80/h apprentice mechanic) converting your N/A to turbo is easier because it can be done is small instalments!

[666DAN]

Geez dan after all these years this thread has been goin on, how much do you think you have spent to turborize ur car and all the stop and gos along the way? The slowness is starting to get to me but i love my car. Im thinking of selling it and getting a manual turbo? what does everyone think? worth the trouble converting or get a GTT?

I spent bugger-all doing the conversion, you've got to remember I did this back when GTT''s were damn expensive (my 25GT was $34K back then!!!! ) My GT + t was stolen and written off a long time ago, I've now got a real GTT.

Seriously the stupid price I've seen parts going for you'd be looking at under $1500 for the conversion DIY over a weekend

[dori34]

yeah, parts these days for nissans are cheap as!

so doing a de+t shouldnt cost too much

[lammy426]

do the conversion its a good learning curve,i have no regrets and the power is still going up

[floody]

Ok well anyone want to critique my current thinking...

RB20DET in my HR31 coupe has died of old age.

I am considering an R32 RB25DE+T setup.

Would comprise of the following...

R32 RB25DE

HR31 RB20 plenum top and throttlebody (cable is on opposite side, will not clear my strut brace otherwise, plenums basically the same)

HR31 RB20DET cams (more agressive than R32 RB20 or 32/33 RB25 items)

Nistuned HR31 RB20DET ECU, sensors, coilpacks.

GT-R 440cc injectors

BB VG30DET Turbo, full 3" exhaust

Blitz LM intercooler

Bosch 984 pump

?Perhaps a thicker aftermarket head gasket?

?Possibly Z32 AFM?

I know the ecu is old however I'm fairly confident the Nistune board would allow it to be more than tuneable enough. Could possibly run a Nistuned R32 RB20DET ECU if totally necessary, however I think with the Nistune setup the HR31 ecu won't be a significant restriction compared to the R32 item

-I do not want a knife edge tune. The car will probably often see high load/knock threshold driving (i.e. between home and work is a steep, wide open throttle, 5 minute long climb at 80kmh in top), the occasional track day. It won't be an every day car though.

-Fuel is a limitation here, it would have to be reliable on Caltex Vortex 95 or BP Ultimate.

-Ideally I want to swap back to my original RB20DET eventually (with a stout rebuild), in a year or two, so I don't want to have to butcher the original loom. This is part of why if possible I'd like to retain the original ecu.

So, would I be able to do this reliably? What sort of power output can I reliably achieve - can I realistically make enough grunt to justify the expense over slipping another RB20DET long motor in? It needs to be a reliable, turnkey performer that could potentially do a few years or more as a weekender and fun car.

Edited April 10, 2008 by floody

[SKiT_R31]

Sounds like it'd be spot on

i wouldn't run a thicker head gasket, doesn't solve anything. It'll make good power on stock boost (7psi on a high comp 25 should eat a 20det on over double that)

DO EET

but good luck finding an R32 25DE, everyone snaps them up for 30det conversions

Theres no reason why you couldn't use an R33 rb25, you could hook all the same electrics up (you don't have to have a plug for vct it will work fine without it) you'd just have the plenum issue - I'm not sure how different they are, if its just port sizing i wouldn't call it an issue.

[floody]

Oh I have a line on a motor...and they aren't that hard to get anyway. Plenum is mainly due to the throttle cable fouling the strut brace on a R33 RB25, and ability to run HR31 RB20DET plenum top on a R32 RB25 which means my throttle body will bolt up and my cable won't be in the way.

I was only thinking thicker gasket as in an aftermarket one, HKS, Tomei etc; standard thickness would be fine I guess and reduce chances of hotspots etc.

At 10:1 comp and the hills here, with our at times dodgy fuel I am a bit worried about detonation though...suppose I could tune it very rich and run Shell V-Power from Autocraft.

[SKiT_R31]

Oh I have a line on a motor...and they aren't that hard to get anyway. Plenum is mainly due to the throttle cable fouling the strut brace on a R33 RB25, and ability to run HR31 RB20DET plenum top on a R32 RB25 which means my throttle body will bolt up and my cable won't be in the way.

I was only thinking thicker gasket as in an aftermarket one, HKS, Tomei etc; standard thickness would be fine I guess and reduce chances of hotspots etc.

At 10:1 comp and the hills here, with our at times dodgy fuel I am a bit worried about detonation though...suppose I could tune it very rich and run Shell V-Power from Autocraft.

i really don't think that compression is going to be a problem, and decompressing it wouldn't really solve anything except kill some of its power, you should really only use them when you've shaved a bit much off the head etc.

Look at Juddo with his 25de+t, didn't stress it in the slightest, and he only ran 95ron, but on like 10PSI, everything stock. On stock boost i really cant see it complaining at all, esp with a good fmic, i wouldn't worry about richening it up (rich enough from factory), maybe wind some base timing out of it, but still would be fine.

If you can run 7psi through a 9:1 CR 30e, you should definitely be able to run 7psi on a 10:1 CR with a good cooler.

as for the throttle cable, cant you just use a std RB30e position one? thats all i did for my 30de, got a thick flat bit of steel, few bends, drilled a few holes, added some spacers and made one shmicko, looks way better than stock, sits at perfect height. When i fit my ff plenum i prob wont need it actually...

Edited April 10, 2008 by SKiT_R31

[skyhighR33]

guys just wondering if i was to do the turbo conversion should i keep the car 4wd or take it to rwd???

[SKiT_R31]

leave it 4wd

[skyhighR33]

cheers i am keeping her 4wd and doing my converstion soon ill keep you guys and gals posted on it.

[josh_gts]

so is it really worth turbo-ing a non-turbo engine?

i have a R33 GTS and i really want more power.

i've considered buying all the turbo parts and doing it, but then thought it would be a headache, so

my next option would be to do an engine swap... RB25DE to the RB25DET, but then all the gear box and ecu

and what ever else needed got to me.

so would it be easier to buy a skyline turbo or a 200sx when im off my P's?

any suggestions would be appreciated

josh

[SKiT_R31]

the n/a gearbox will handle a 25det just as much as it will handle a 25de+t, ditto for clutch

^ the gearbox should be ok with it, pending how you treat it

The ecu has to be changed anyway

I'd rather run 7PSI on an n/a engine that i know and trust, over 10psi on a random engine, to make the same power.

You'll hit the ecu power/airflow restriction before you have any other problems, just the same as with the 25det, but on less boost (as its drawing in more air and making more power)

Id rather rebuild the N/A bottom end with some lower comp pistons than waste money on a flogged 25det

And changing all the turbo bits over is easier/less hassle that an engine swap any way imo

that said, if your not attached to your car, buying a turbo model is definitely the easiest and possibly cheapest option, as brakes, etc are already upto spec just if you don't know a ot about cars/engine, get some one who does to have a look over it for telltale signs of water pump, oil seals etc, test CR etc. As if its a turbo import in Australia, its been thrashed.

[josh_gts]

thanks for that, i'll keep it in mind.. its just one great issue in my mind of what to do lol