Rb25 into R32 skyline

[S13 180]

Hi new to the site was told this is the place to find the info im after so here i am im doin a conversion for a friend on a skyline and was after some info or a site (link) telling me what i need to change to make it work,its an R32 with a blown Rb 20 and he wants to run a Rb25det and i was wondering if any one has performed it.

Any info would be great as he has already purchased the motor and loom and comp so im after some help regarding installation. :newbie:

[blind_elk]

If you have the engine, loom and comp, then it's a straight swap. Pull the RB20 out, put the RB25 in.

To change the loom, it's easiest if you remove the LH guard.

And fit a new clutch assembly while you have access to it.

[funkymonkey]

i'm 50% thru the process. But I'm goin for a Power FC for management because of the different sensors and the difficulty of connecting the sensors to the RB25 computer.

[Blue32]

Just finished conversion in my 32 and if you have a bit of mech knowledge it was piss easy. Recommended timing belt/water pump change prior to fitment

All that was required is:

Remove rb20 - leave ancillaries still in car (alt/pwr steer pump/ a/c and starter mtr

1) All rb20 ancillaries bolt straight up to rb25 (a/c + alt bracket is identical)

2) use rb20 engine mounts on rb25 (straight fit)

3) Heater hoses (at back of engine to firewall) are smaller on rb20 than rb25 - either make adapter to step down size from rb25 - rb20 or do what I did and heat up (in boiling water) the ends (the smaller rb20 pipes) that go on the engine, and expand them with pointy nose pliers, lube them up (car wash or detergent) and then slide them on. Simple fix.

4) Replace oil pressure SWITCH sender on rb25 (sensor under oil filter) with oil pressure SENDER unit off rb20. The alt/str mtr loom has the plug for this so connect it when the eng goes in.

5) replace the water temp sender (the smaller single blade plug type sensor) with the identical looking one off the rb20. The calibration of the wtr temp gauges is different between models - this will ensure your gauge still works correctly.

6) Change the harmonic balancer to the rb20 one to ensure your pulleys all line up with the belts.

Also get an r31 (i think) skyline top radiator hose or r33 to fit - the rb20 bottom hose fits

7) The computer pwr/ign/inj pwr loom is the rectangular plug behind the airbox just next to the pwr steer resovoir - trace the wires and make adapter loom for the rb25 computer loom. (no need to remove lh guard????!!!!)

8) Trace wires for the windscreen wiper motor and connect in to the motor and in the foot well

9) Only speed sense, a/c trigger, tacho ( i think thats all) needs to be traced and connect in the foot well and then you are good to go!!

Be advised your strut brace (like mine) may not fit after fitment as the engine is slightly taller (due the inlet manifold height)

This conversion is the sh%t - the car is sssoooo driveable now - no off boost dull boring rb20 lacking torque - go through roundabouts in 3rd and accel out from 30km/h no probs. Oh yeah - if you fit a pwr fc and wind up the boost, the rb25 in the dry is just like the rb20 was in the wet - driftin' easy!

[A31_Cefiro]

Just a quick Q asI recently found out my engine is dieing and needs to replaced so looking at options.

Did anyone use the RB20 gearbox or did you all swap to the RB25DET gearbox. I'm just wondering on driveability and reliability of these boxes behind the bigger engine.

I understand that it would be easier to blow the box but if you aren't doing burnouts etc how risky is it?

Thanks.

[Spagman]

Does the battery also get moved to the boot like in the r33 or is there room? Im just curious :looney:

[S13 180]

Blue 32 on the drivers side of the engine did you leave the original Rb20 loom for the starter and alternator, if so how did you hook up the knock sensors on the Rb 25.

Cheers Great info by the way

[Campster123]

Wat sort of power gain and time gain (1/4mile and 0-100) would you get going from a stock rb20det -> stock rb25det in an r32 gts-t? And which is the more reliable motor with the most potential?

[predator]

both are reliable as rocks.. if nothing silly is done.. rb25 is torquey with get down low to go go go. rb25 has the advantage of more aftermarket parts being direct fit these days.

very useful info blue, will come in useful.. i just picked up an rb25 complete today for silly price

[CSV Imports]

I'm not quirte up to doing this conversion myself, so roughly how much would it cost me to buy the engine and loom and comp and get it professionally installed?

[MerlinTheHapyPig]

i'd imagine a workshop would charge outragious prices for an engine swap (regardless of whether it's an easy swap or not) and you'd probably want someone who has a bit of knowledge about skylines and has done the swap before. Best idea would be to ask around on the forum and see if someone whose done the swap before needs a bit of spare $$$

I think the suggestion has been made in a previous thread to do the fitting yourself but get an autoelectrician to wire up the loom, (which is apparently the hardest thing - that was suggested on a previous thread on the topic)

Anyone done any RB26DETT conversions? Im thinking on waiting until my RB20DET blows up and then put an RB26DETT engine + RB25DET gearbox in it and go driftin :-D (mmm rear wheel RB26DETT)

[CSV Imports]

Ok, so how much for the front cut or watever I need then?

[MerlinTheHapyPig]

http://www.justjap.com/welcome_page.htm

RB25DET 5 Sp $5,000

RB25DET NEO 5 Sp $6,000

RB26DETT 5 Sp R32 $7,500

u will have to call to see if they have any in stock, all the prices are "From $..." so i think they're minimum prices

What's the diff between rb25det and rb25det neo??

[predator]

There are cheaper places to get complete motors than there if you are going that route.

Best option is to try and source the front cut directly from japan.. or through somebody locally who has written off their car and who wants to get rid of it quickly. You can get a good motor around the $2k mark, but you have to shop around, know some people and/or be quite lucky - thats definitely not an "average" price though.

West's car for example you could buy, pull the motor, and sell the rest and you'd be getting a very cheap rb25det..

[Campster123]

Merlin - I'm seriously considering doing an RB26DETT conversion when my car gets here...

That'd make it a - Garage Impul R32 4 door AUTO RWD sedan with a GTR engine...

Other than just converting the engine I think I'd be looking at high-stall converter (+maybe strengthening the the auto box if needed although apparently they are pretty good) and prehaps a brake upgrade (its already got tuned suspension). Then a light tune on the engine and I'll be aiming for 12s 1/4miles

[boj01]

RB25DET Neo motor is from the R34 GTT

[MerlinTheHapyPig]

im gonna wait until my RB20DET blows itself up then look at doing a conversion, though a RB26DETT might be a little too good, especially since i'll probably be drifting it.

i have no idea how the RB26 will go with an auto box. you might be better off with a RB25DET from an R33 skyline and putting a bigger turbo on it. Saves hassel coz u just have to find a R33 half cut with an auto transmission.

[Starionturbo]

I have a 1995 RB25DET in my R32 - it was the only one of 2 In Perth. I absolutely love the car and its really miles ahead of a RB20. The power down low is crazy and because its a lighter car it REALLY gets up and goes, on the run its phenomenal.Best conversion runs like a dream BUT MAKE SURE U GET A RB25DET Gearbox!!!! RB20 box wud shit itself if u drove it hard

Mine with only a Full exhaust system, FMIC and Rom is getting 280 rwhp.

Only needs a about 330rwhp and ur looking at 11s.

regards

Kim.

[Bax]

Mmmm, how much did you pay for it, with conversion or did you do the conversion yourself?

How much did you pay for the conversion?

Definately worthy though, it was something I wanted to do when I was looking into the 32's.. Didn't like the idea of the rb20.. Not quite big enough capacity for my likings.

[Blue32]

My car made 210rwkw on Friday when I got the Pwr FC tuned on 1 bar. Goes really good now - the rb20 on 1 bar std computer only made 160kw!!!

I strongly recommend the conversion as the extra torque is a god send - also the fact that the standard engine can make 210rwkw on 1 bar (with the usual fmic, exhaust, cold air induction/pod filter, r33 gtr fuel pump) is a good enough reason for me. The next mods will be probably 2835 or gt30/35, bigger injectors and maybe a 1.4mm head gasket for a solid 280 - 300 rwkws with enough torque to pull over a house (figuratively speaking - maybe not compared to a mining truck!!! I also have used the rb20 g/box currently - when the minister for finance allows another 'relaxing of the budget' i will upgrade to r33 box. FYI I think it needs a small trans tunnel massage (rubber mallet!) and the r33 auto x member. Also the r33 g/box yoke needs to be joined to rb20 tailshaft along with corresponding change of tailshaft length. Haven't measured it yet but will post once I do.

s13 180 - i did leave the starter/alternator loom from the r32 in the car - the knock sensor loom is seperate and plugs into engine loom on rb20. The rb25 knock sensor loom (from memory) was incorporated in the rb25 starter/alt loom. I simply stripped it back till i had only the rb25 knock sensor loom and plugged it in wherever it went onto the engine loom.