Rb25 Into S13

[bad_rb20]

hi all, rb20 motor is looking a lil tired playing with the possibility of putting a rb25 in it,

What's everyones thoughts ?

I know the 20's are lag monsters but when they hit boost theres just sumthing about them that makes you smile.

ANyways what i also wanted to know is how much it would cost to chuck an rb25 in my already rb20 powered s13.

I can get a motor with loom, ecu and all the shit minus box for 1500 or so,mechanic said he could strengthen the rb20 box for me for cheap.

So what i really want to know from people that know what they are talking about is how much it will cost to get the loom all working, with the rb25 put in. Is there anything else that will have to be changed excluding the loom, as there was already a rb20 in there?

If anyone could help us out with there experinces. Any useful info is appreciated

Thanks boys

Nathan

[Simon-S14]

go the 25, they are awesome, ive had two RHB20 powered cars (and my gf has a stock 32 so that makes 3) and now ive got a 25 in my 32 and i love it!.

You have several options, one is to put ALL the RB20 sensors on the 25 (CAS, knock sensors, ignitor, etc etc) and use the RB20 loom and ECU, remap the ecu and your laughing.

other option is to use the 25 sensors and 25 loom, and still with the RB20 ecu (remapped and tuned to suit of course) with fuel pump, fmic, exhaust you could expect to see 200 + rwkw with a stock turbo on under 14 psi (like 12 psi) the stock ecu wont do this.

as for the box... there is no strengthing the rb20 box "cheap" unless your putting straight cut gears in it.,.. however if you plan on keeping it around 200 rwkw and driving sensibly theres no reason why it shouldnt last. with some drift and track work it will soon die.

Cheers

[bad_rb20]

cheers for the quick response mate,

so if i go witht he rb25 i will also have to factor in remapping the ecu? which is a good $600, is there anyway you can use the r33 ecu and have it running like that?

with both the options with wiring, how much would it cost to hack up the loom like that?

how much did your conversion cost roughly excluding motor mate?

Thanks for the help

Nathan

[SirRacer]

there are loom diagrams on here somewhere and there are only a few minor differences between the 2 looms, so i think with a little bit of tweaking you could run your stock loom

[Simon-S14]

of course you can use the stock 33 ecu, but they limit you in terms of power and mods... you'll hit rich and retard quite early.

BTW remaps can be had for hell of a lot cheaper then 600...

[bad_rb20]

are remaps cheaper then that ? where would be a good place to get remaps, so how much id it cost to convert yours or did u do it yourself?

how much do you think the whole wiring proccess would cost with getting the motor out/in?

Cheers mate

Nathan

[R338OY]

If you ask around a remap won't be expensive. I was offered one for $350, but didn't go for it so can't give any further info!

RB25 ftw!

[13thracer]

Do the 25 you will never look at your 20 the same again, the loom would be an easy job for any capable mechanic couple of hundred to fit and make work, personally and this is just me but i would live with the 25 ecu and run stock boost until you can afford a power fc or equivilant the remap is good but any further mods down the track will require remapping not just retuning which is done by alot more workshops,

With conversions i recommend getting everything running sweet on the stock ecu first drive it for a little bit then start stuffing around with aftermarket ecus. i did this in mine with just cooler/intake and exhaust stock ecu stock r33 boost solnoid (6 to 8psi) made 220hp at the rears no R&R either and in a silvia was plenty to keep me happy until i could afford the ecu upgrade.

long story short put the 25 in deal with the problems that will happen and in the long run you will have so much fun

pm me if ya want any more details more than happy to help

[13thracer]

oh yeah ive got a stock 20box in mine too which has lasted the 18 months ive had the car and hopefully longer all depends how you drive i spose

[boot_it]

hi all, rb20 motor is looking a lil tired playing with the possibility of putting a rb25 in it,

What's everyones thoughts ?

I know the 20's are lag monsters but when they hit boost theres just sumthing about them that makes you smile.

ANyways what i also wanted to know is how much it would cost to chuck an rb25 in my already rb20 powered s13.

I can get a motor with loom, ecu and all the shit minus box for 1500 or so,mechanic said he could strengthen the rb20 box for me for cheap.

So what i really want to know from people that know what they are talking about is how much it will cost to get the loom all working, with the rb25 put in. Is there anything else that will have to be changed excluding the loom, as there was already a rb20 in there?

If anyone could help us out with there experinces. Any useful info is appreciated

Thanks boys

Nathan

i would advise not to wire up a rb20 ecu to suit the rb25det as ppl forget that a rb25det has vct and the rb20 ecu doesnt support the vct and if u search around on this site there is a thread about vtc not being connected up and the car running like a pig

unless u use some external switch to switch the vct on

just get the rb25det loom wired up to suit your car and buy a pfc

[bubba]

Or you could build an RB30 with a 25DE head out of an R32.. I did that, swapped everything over from the 20 and ran it on my 32 ecu

(It did max out a lot of things though so 550cc injectors, z32 afm and a remap later and she's driveable.. had a chipped ecu with no R&R which got me around for a couple of months before the tune)

[bad_rb20]

so should i be bargaining around 5k for the whole thing done?

[bubba]

Including purchase of motor?

I did a lot myself and I have a very good mechanic.. so labour doesn't cost me anything other than buying him lunch and/or dinner when we're working

[bad_rb20]

well i got quoted over the phone to get it installed completely for 2k around

and i can get a motor for 1500 so 3500 all should be well:P

any other lurking costs?

[STATUS]

any other lurking costs?

bad weight bias, and if must '6' it go a 25. a sr20 is a better bet than a rb20 all day everyday.

[bad_rb20]

also anyone know a good place to do engine conversions in sydney?

Nathan

[Simon-S14]

bad weight bias, and if must '6' it go a 25. a sr20 is a better bet than a rb20 all day everyday.

so why did you go the 26 if the bias is that bad??

VQ30det FTW for ultuimate bias and power

[STATUS]

so why did you go the 26 if the bias is that bad??

VQ30det FTW for ultuimate bias and power

for fun the sr was a way better setup handling wise, it took all 5 events to get it to work as well as the sr setup.... yet when it rains...... all the hard work is pointless

maybe i'll have a sr20 supra out there late next year.... we will see.

[1400r]

so why did you go the 26 if the bias is that bad??

VQ30det FTW for ultuimate bias and power

VQ30det are gay go VK57det

[bad_rb20]

so is there any other hidden costs i should know about ?