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i really love the reliability of the Rb20 engine but im onto my 3rd rb20 gearbox with only 150kw i don't wanna pay $500 for another, when it may only last a week!

so im considering an rb25 conversion if i do the box i may aswell go the engine too, im only after 200kw i mainly just want a bulletproof setup.

im interested in what actual costs to get it on road are, i can do all the work myself and should be able to get a halfcut for 3-3.5k?? then maybe add another $1000 for tailshaft mods, tune, fluids, gaskets, belts etc.... sound right? how cheap can it be done reasonably?

i've never driven an rb25 but people seem to say its a different world to an rb20? response is definitely something i'd like more of!

im interested in opinions from people who have done the conversion, what it cost them and how it changed the car.

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sorry dude, normally i hate ppl that say this, but DO A SEARCH>!!!

this topic is one of the most widely covered and repeated of all topics since the beginning of SAU - i think if you do a search you will find a MOUNTAIN of info on opinions and how-to's.

In short, the answer is YES. RB25 shits all over RB20.

250rkw RB25/R32 = 11sec :)

do it.

sorry dude, normally i hate ppl that say this, but DO A SEARCH>!!!

this topic is one of the most widely covered and repeated of all topics since the beginning of SAU - i think if you do a search you will find a MOUNTAIN of info on opinions and how-to's.

In short, the answer is YES. RB25 shits all over RB20.

250rkw RB25/R32 = 11sec :)

do it.

Yep, plenty of threads saying how worthwhile the conversion is and what exactly is involved. Just did it to mine a few months and I'd also say definitely worth it.

you broke 3 gearboxes? Maybe if you stopped raping them at every chance that might help!

Naa that won't happen its too much fun hearing it scream

Rb30det is overkill for my application i only plan to run the stock turbo, to be honest im pretty happy with the 150kw ive got lol

Edited by battery
theprodaniel.....what was ur final cost for the conversion then?

$2500 on motor loom ecu ect

$400 on wiring from auto elec

maybe $200 -300 on hoses I replaced, adapters and fluids

Still babying 20 gearbox but going fine so I would have spent around $3100ish doing everything else myself. Sold old coilpacks and rb20 and still have a bunch of spare stuff.

i was contemplating both rb25 and rb30 conversions for quite some time.

But i was thinking of saving up a bit more and buying an r34 gtt, basically coz its newer, no head aches with cops, the nicer engine..ect

i was leaning towards r34 thats why im selling my gear,

but every time i think about it i end up changing my mind

what are your opinions??

R32/rb25

R32/rb30

R34 gtt - pushing around 200rkw for now

would the extra weight of the r34 make that much of a difference?

...

In short, the answer is YES. RB25 shits all over RB20.

250rkw RB25/R32 = 11sec ;)

do it.

:) damn thats quick.

would a 250rkw r34gtt be as quick?

edit: btw battery, i also really enjoyed my rb20 when i had it, it was the best fun. It wasn't my decision to get rid of it so i guess it was a sign that its time for a change. lol.. And Sorry I couldn't help u out with your questions, my bad for stealing your thread.

Edited by def_jamz112
:) damn thats quick.

would a 250rkw r34gtt be as quick?

Well considering the 32 is lighter, clearly not.

We did this conversion in my mates car a month or so ago, he spent 3k on a written off 33 S2 (quite cheap), we had the engine loom done by a guy on here who does them for $350, you send him your R32 loom and R33 loom and he sends you one back that you plug in and start the car ;)

Thats all he spent really. With about 3 of us doing it, we got it done in 2 days. If you had a mechanic do this I would expect 2-3k in labour. Although we didnt put the 25 box in, thats for another rainy day. Maybe $2-300 in tailshaft, speedo and crossmember modifications...?

Driving it after, all stock except for a Greddy Turnflow cooler, and 3" exhaust, it was QUICK! It snapped second all the way up the road!

Having said that you could still get the same peak power with a HKS2530 on your RB20, although you would have no-where near the amount of low end power/midrange the 25 engine does.

Id drive a 33 and see how they drive, it will make your mind up real quick.

i was contemplating both rb25 and rb30 conversions for quite some time.

But i was thinking of saving up a bit more and buying an r34 gtt, basically coz its newer, no head aches with cops, the nicer engine..ect

yeah i've though about this aswell a decent one with few mods is $20k i reckon if i sold my 32 i'd be lucky to get 8k as its pretty ruff and the box is farked, but the conversion should cost under 4k which makes it a much much cheaper option than the GT-T.

theres also things like theft to worry about a little more than the 32.

but it depends on the individual i guess, i mean you could put a 34 engine into the 32 also, i saw a frontcut for 4.3k.

theres also things like theft to worry about a little more than the 32.

Been there done that.. thats how i lost my 32. :)

FEMNO - I have taken a r33 for a test drive, and to be honest it didn't really impress me that much..

I could definitely feel the weight difference, how much bigger it is, and the power delivery was more linear (maybe i was used to the rb20, nothing, nothing, nothing, wooooooo).

I couldn't really push it that much though b'coz the sales man came with me :(, it may or may not be quicker but i jst didn't enjoy it as much.

Will the weight of the 34 make it fell like a 'commodore' lol? and will it make it harder than the 32 to throw around in the turns?

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