S13 - Rb20 Conversion

[gelousi]

Hey guys, I just finished my s13-Rb20 conversion and would like to post up afew tips since i had to learn the hard way were my alternator was incorrectly wired up and was giving the motor a constant 15v which caused a misfire and destroyed a coilpack, so on first start up get a multimeter and measure voltage at battery while engine running shouldn't go more then 14.4v

This is just a guide from my experience i take no responsibility for anyones faults

To do the conversion you will need the following

Rb20 K-frame

S13 Gearbox mount

S13 Tail shaft (manual)

Rb20 Motor + loom + ecu

Ok so once you pull out your old motor change the k-frame over but use the std s13 power steering rack and pump, the motor will drop straight in and everything will bolt straight up thats the easy part

For the wiring you will need to do the following,

There is a 8 Pin plug with Spade terminals right near the front left headlight off the rb20 loom, there will also be another plug on the s13 body loom and you will need the following

Grey Plug

s13 Black/Red join to Rb20 Black red and white/purple is your ignition

s13 Red join to Rb20 White Black ecu memory backup

Brown Plug

s13 Orange on another plug next to your powers is your fuel pump which is the Black/Pink wire near the ecu plug (run a wire from ecu plug to fuel pump)

Now thats done you will need to swap over your starter motor loom, will all unplug and plug in just don't worry about the knock sensor plug as the rb eng loom has it. Everything should plug straight back in

And thats it your done you should have your rb20 running in your s13

If motor was previously a auto there will be a two pin plug with fat wires that go to the gearbox loom you need to join the two pins together so that the car cranks.

For your cluster connections please follow the following,

Note i have only used this to connect my temp guage for now and for it to work you will need the temp sensor off your old motor in the s13, its just a 12mm nut with one spade terminal coming out of it

RB

Plug 1

Gnd – black with yellow stripe (ground)

Tm – blue with black stripe (temperature gauge)

Oil – yellow with white stripe (oil light)

Belt – yellow with black stripe (seat belt light/chime?)

Door – red with white stripe (door open light)

Exh – orange with black stripe (exhaust gas sensor light)

Ign – green (ignition switch power)

Acc – blue (clock power)

Bat – yellow (no idea)

Plug 2

Ill+ – red with blue stripe (illumination power)

Ill – black (illumination ground)

Om – yellow with blue stripe (oil pressure gauge)

Tam – yellow with red stripe (tach signal)

Beam – black (high beam ground)

Beam+ – red with green stripe (high beam light power)

Gnd – black (ground)

Sw1 – yellow with green stripe (no idea)

Sw2 – black with yellow stripe (no idea possible ground)

Hicas – green with white stripe (hicas warning light)

Brk – white with purple stripe (handbrake/brake fluid warning light)

Chg – white with red stripe (alternator charging light)

Plug 3

Ign – green stripe (ignition switch power)

Bm+ – white with blue stripe(boost gauge signal)

Bm – black with yellow stripe (boost gauge ground)

Fm – green with blue stripe (gas gauge)

Gnd – black with yellow stripe (ground)

Fuel – red with black stripe (fuel warning light)

T/l – white with green stripe (left turn light)

T/r – green with yellow stripe (turn right light)

S13

Plug 1

Chk engine – red (check engine light)

Cruise – black (cruise control ground)

Cruise+ – green with white stripe (cruise control light power)

Abs – blue with red stripe (abs light)

Exh – red with blue stripe (no idea, different on every car)

Fm – green with blue stripe (fuel gauge)

Fuel – red with black stripe (fuel light)

Ill – red with yellow stripe (no idea)

2p – yellow with green stripe (no idea)

Japanese symbols – yellow with blue stripe (no idea)

Plug 2

Ill+ – blue (clock illumination)

Ill+ – red with blue stripe (illumination full)

Tam – yellow with red stripe (tach signal)

Japanese symbols – yellow with black stripe (no idea)

Beam 1 – pink with black stripe (high beam ground)

Beam 2 – red with green stripe (high beam light)

T/r – green with yellow stripe (right turn light)

T/l – green with black stripe (left turn light)

Gnd – black (ground)

Plug 3

Door – red with white stripe (door open lamp)

Ign – green (ignition switch power)

Oil – yellow with white stripe (oil pressure light)

Brake – yellow with purple stripe (handbrake/ low brake fluid light)

Tm – blue with black stripe (temperature gauge)

Chg – white with red stripe (battery light)

Gnd – black (ground)

if anyone needs any help feel free to pm me

and maybe we can sticky this thread i dont know if its in the correct section

So now that mine is finally running 100% it has really good tourqe and power more then a stock sr

[Dose Pipe Sutututu]

I wrote a guide a while back detailing the wiring

http://www.nissansilvia.com/forums/index.p...p;#entry3954339

RB20_into_S13.pdf

Edited May 21, 2010 by johnnilicte

[gelousi]

yeh i think i followed that guide but it didnt say anything about alternator wiring? unless i read it wrong

[hornby88]

im about to attempt this conversion myself, why is it best to use the ca18 rack and pump? will the pump bolt to the rb20?

[Rolls]

Nice post but I never understood why people went the 20 over the 25, it is basically a downgrade from the sr20.

[hornby88]

does a 25 bolt to the same k frame?

i wanna do rb20 i guess to be different sorta but also due to how much cheaper i can get a halfcut

[joeyjoejoejuniorshabadoo]

Nice post but I never understood why people went the 20 over the 25, it is basically a downgrade from the sr20.

agreed.... would take an SR20 over an RB20 anyday

[STATUS]

Nice post but I never understood why people went the 20 over the 25, it is basically a downgrade from the sr20.

exactly, and it makes em handle like shit.

[gelousi]

exactly, and it makes em handle like shit.

Its not that bad, i re-gapped my plugs to .8mm and the splatter has gone i forgot to do that before i took it to you. And the power it has is awesome! I guess we will find out how it handles at winton lol

[gelousi]

im about to attempt this conversion myself, why is it best to use the ca18 rack and pump? will the pump bolt to the rb20?

You can use rb20 pump but u need to remove the inside "guts" for the hicas or power steering fluid will leak everywere (which i learnt the hard way) lol and its less work to use the std pump and rack, altho the pump will bolt onto the rb20 but doesnt sit straight, I found the easiest way is to get the pump bracket off a rb20de which is a non hicas pump wich is identical to the s13 ca pump

[Rolls]

Its not that bad, i re-gapped my plugs to .8mm and the splatter has gone i forgot to do that before i took it to you. And the power it has is awesome! I guess we will find out how it handles at winton lol

rb26 > rb25 > sr20 > rb20

the sr beats them all for size and weight though. Seriously the rb20 is bigger, weighs more, makes less power and torque for any given turbo combination, it's only advantage is it sounds brilliant and will hold together at extended high revs for longer.

You can use rb20 pump but u need to remove the inside "guts" for the hicas or power steering fluid will leak everywere (which i learnt the hard way) lol and its less work to use the std pump and rack, altho the pump will bolt onto the rb20 but doesnt sit straight, I found the easiest way is to get the pump bracket off a rb20de which is a non hicas pump wich is identical to the s13 ca pump

rb30e pump works as well from what ive heard.

Edited November 12, 2010 by Rolls

[hornby88]

i bought my rb20 conversion few questions do i take out the main power loom it runs into the guard or do i use the s13 one?

[gelousi]

use the s13 one which is just near the passenger headlight

[Tree Fitty]

I used a C31 cefiro cross member and rb30 engine mounts. Sits the engine much lower.

[discopotato03]

I think the bottom line is that an R32 GTST with an RB20DET is a better car than an S13 with an SR20DET . I believe the curb weight is similar but the Skyline is a much better package by comparison .

The other advantage is that so many parts bolt/plug into the Skyline so works out cheaper in the long run .

The woes with the RB S13 start with a huge weight injection up front and move to inadequate space to fit a proper cooling system .

For the 101 th time I cannot understand why people don't follow what Nissan did with S13/14 and fit a KA24 16v twin cam four cylinder like in USDM 240SX's . All the gear is available in the US so manifolds etc are no problem .

Big torquey four thats factory engineered to work in the S13/14 platform .

I think the RB S13 idea germinated years ago when CA based S13's were cheap cars and RB20DETs were also cheap and plentiful .

If I really had to have an RB in an S13 it would be an RB25DET because everything about them is better (IMO) .

It could sort of "balance" out because the chronic understeer at the front and lack of traction at the rear at least means its lack all round . I guess all I can say that is good about the idea is that if you can drive well drift style you may be able to work some advantage if you can rotate the car about its center of mass because its just so far forward compared to most things . The original Audi Quatro was a very front heavy car and actually worse in the later shortened Sport version , at least being AWD they got the power to the ground though watching Walter Rohl pivoting the 500+ Hp around such a front heavy car is an eye opener . Grab a copy of "Too Fast to Race" and note how the Group B Quartos were driven and how the smaller/lighter/more nimble 205 T16s later carved them up .

Poor weight distribution has killed the effectiveness of so many cars and theres basically no fix for it .

Sorry to be negative but its the reality of the thing .

A .

[Tree Fitty]

The weight distro isn't as bad as people make it out to be. "Chronic understeer" is an overstatement.

[jamie1990]

hey all. doing this conversion. got everything working minus all the dash gear. speedo,temp,fuel and tacho.they hate life. soooooooo the previous owner hooked up the vss direct to the speedmeter but still didnt work. done the 32 rpm gauge swap and still nothing. the wies are all hooked up for it but yeah still not working.any ideas?

[GTSBoy]

Please define what you mean by vss.

You do realise that the VSS is the Vehicle Speed Signal, as available on the wiring that connects to the ECU pin. It is an OUTPUT from the speedo. The speedo needs a signal from the speed sensor in the gearbox. RB20DET gearboxes do not have this sensor, because they have a cable driven speedo.

As to the rest of it....I'm assuming that it's all just wired up wrong.

[Dose Pipe Sutututu]

I recall back close to 15 years ago, I used a VL speed sensor and wired it up for the RB20 box in my 180SX. 

Probably not useful info lol.

[GTSBoy]

What do you mean "not useful"? !!!

People would give an arm and a leg for there to be a tool that you could use to search for information like this. If only there was one.