Rb20det Engine conversion

[stagefumer11]

Well, its finialy time where ive bitten the dust and decided its time to give up the old l20et and go with the rb20det.

I Would like to get a database together from all the information you guys have learnt yourselfs doing this swap. Which i will greatly need.

What is needed for the wiring system, i know the engine side of the loom is simple. But Ecu power. and Fuse box.... ?

[66 skyline gt]

i have changed over to an rb20det in my 66 prince skyline gt.... wot is the platform you are starting with( just the engine or complete package?) can take photos of wiring on mine and can give you general idea of wot to hook up if ya wont?/.... just let me know........

if ya wont to look at my cdonversion, half the photots are posted on my web page... addresss in my signature.....

[stagefumer11]

its going to be going into a R30 coupe, its my daily driver. so wont be doing the swap just yet.

Ive currently only just got the motor, which is in parts. Going to rebuild it competly, new bearings ect.

Trying to find a GTS- GTS-t loom, and then a ecu. hopefully that would help me,

Im planing on using the l20et gear box, according to justec it bolts right onto a Rb bell housing.

[discopotato03]

Yes the L20 will bolt to the RB20 bell housing , you will need the larger countershaft bearing (std on N/A VL and Series 3 Bluebird) and the matching bearing cover/input shaft support . I think the L20 box has small style selector shafts so RB bellhousing may need to be bushed to support them .

[discopotato03]

I'll stay tuned here as I'm very interested in pics of engine and gearbox mounts for RB's in R30's . Pics of the wiring would be great .

Cheers A .

[george.bryant]

Can anyone tell me if bellhousings are easy to remove? Will the rb20det bellhousing fit straight onto the l20et gearbox?

What driveshaft needs to be used in a r30 that has had a rb20det and rb20det gearbox into it?

[rsx84]

my tail sharft was modified, to use the r32 box.

[66 skyline gt]

im running complete silvertop motor and box.... stronnger and will bolts straight up to orginal mount

and the L series tail shft yoke is the same spline as the rb box......

[Ghostrider]

The RB Gearbox output shaft is different, hence rsx's tailshaft mod, a new yoke to suit the RB box is required, but Stewart Wilkins here in NSW is currently modifying an L series front housing for me, so that I can have an RB20DET box behind my L20/28ET ha ha.

The RB main bearing is much bigger than the L series, I'm not sure about the reverse, but RB boxes can be made to go on L6 engines relatively easily.

[Ghostrider]

I'll stay tuned here as I'm very interested in pics of engine and gearbox mounts for RB's in R30's . Pics of the wiring would be great .

Cheers  A .

<{POST_SNAPBACK}>

A,

Jaustech in Adelaide claim the L6 crossmember is used in R30's, with RB engine mounts, but the gearbox rear mount has to be extended backwards.

D

[V8skylineMAN]

hmm.....

my C210 talishaft fits an rb20 5 speed.

ive got the rb30 into the silvercoupe now....just need hubs now

[discopotato03]

Hi all , don't want to lock swords with you Dennis but its the Turbo RB25 box that needs the different yoke because of its larger mainshaft and splines . Jacko and I found this out years ago when we were playing with Bluebird/DR30 and RB20DET boxes . The input and output shaft splines are the same both ends for all three as is the approximate length of these boxes . We know this because the last box he built me for the FJ Bluebird had a full set of RB20DET guts inside FJ DR30 casings which externally are same dimensions as L20B Bluebird box - except different bolt pattern for FJ block .

I will never do this again because there are many differences between early and late selector mechanisms which can be hybridised but the shift quality suffers .

To get an RB20DET box behind an L series is straightfoward , basically ditch the RB bellhousing and bore the lower or layshaft bearing hole in the L series bellhousing to suit the larger RB style bearing outer race . You need to use the RB's larger front bearing cover/input gear support because it suits the larger lower bearing . Now it will bolt together using std bits as per normal .

From what we can see the RB71C is the last and strongest evolution of the 71 series gearboxes . It has the wide gears , the larger syncro hubs/baulk rings ie 1-2 and 3-4 . It has the later shift mechanism and all large size selector shafts . Nissan would have gone beyond these to support higher torque loadings because there comes a time when the only way to strengthen a box is to use larger diametre gears/shafts/bearings hence the larger box used behind RB25/26 turbo and N/A/turbo VG30 four cam engines . The VL-T also has a variation with slightly wider ratios which is good because you can buy a yoke to suit these big boxes that uses rebuildable uni joints .

Cheers A .

[Ghostrider]

Hi all , don't want to lock swords with you Dennis but its the Turbo RB25 box that needs the different yoke because of its larger mainshaft and splines . Jacko and I found this out years ago when we were playing with Bluebird/DR30 and RB20DET boxes . The input and output shaft splines are the same both ends for all three as is the approximate length of these boxes . We know this because the last box he built me for the FJ Bluebird had a full set of RB20DET guts inside FJ DR30 casings which externally are same dimensions as L20B Bluebird box - except different bolt pattern for FJ block .

I will never do this again because there are many differences between early and late selector mechanisms which can be hybridised but the shift quality suffers .

To get an RB20DET box behind an L series is straightfoward , basically ditch the RB bellhousing and bore the lower or layshaft bearing hole in the L series bellhousing to suit the larger RB style bearing outer race . You need to use the RB's larger front bearing cover/input gear support because it suits the larger lower bearing . Now it will bolt together using std bits as per normal .

From what we can see the RB71C is the last and strongest evolution of the 71 series gearboxes . It has the wide gears , the larger syncro hubs/baulk rings ie 1-2 and 3-4 . It has the later shift mechanism and all large size selector shafts . Nissan would have gone beyond these to support higher torque loadings because there comes a time when the only way to strengthen a box is to use larger diametre gears/shafts/bearings hence the larger box used behind RB25/26 turbo and N/A/turbo VG30 four cam engines . The VL-T also has a variation with slightly wider ratios which is good because you can buy a yoke to suit these big boxes that uses rebuildable uni joints .

Cheers  A .

<{POST_SNAPBACK}>

AS usual your a wealth of information, and thanks, as ya just saved me a few bucks buying a yoke/tailshaft for mine when I swap the RB20DET box into my PNV.

The only thing I might have a problem with is the length, cause I am told the L20ET uses a stumpy short gearbox, as opposed to the RB being quite longish.

Cheers, D

[stagefumer11]

So with this swap.. You can use a rb20det hear box on any l motor, with simple mods? What would become with the Driveshaft. ?

My l20et box is getting a bit "solid" in shifting, id like to go with a rb20det gear box

[discopotato03]

So with this swap.. You can use a rb20det hear box on any l motor, with simple mods? What would become with the Driveshaft. ?

My l20et box is getting a bit "solid" in shifting, id like to go with a rb20det gear box

<{POST_SNAPBACK}>

It sounds like the HR30's use a similar/same box as the MR30's . Could be a simple cheap fix if you found one for the right price .

Cheers A .

Forgot to add , if you change that lower front bearing to the smaller earlier type the "L" bellhousing should go straight on . I think my hybrid FJ/RB20 box was like that after its innitial build . It was in and out 2 or 3 times trying to get it right .

For the 130 KW you may not need the hassles of the big front bearing conversion , FJ20ET's made 143/147 Kw (early/late) and they did not get the big lower front bearing and don't seem to eat them in std or mild state of tune .

Bye .

[discopotato03]

For Dennis , there is a chance that the wide gear set with the big syncro hub/ring/fork 1-2 (basically FJT set) may fit the "stubbie box" , the main changes were the rear extention housing and mainshaft length (obviously) selector rods as well . Provided the mainshaft gear bearing journals are the same it may be possible to get tougher bits onto the "stubbie box" mainshaft and if she's worth it even the larger lower front bearing .

It would at least look original !

Cheers A .

[Ghostrider]

For Dennis , there is a chance that the wide gear set with the big syncro hub/ring/fork 1-2 (basically FJT set) may fit the "stubbie box" , the main changes were the rear extention housing and mainshaft length (obviously) selector rods as well . Provided the mainshaft gear bearing journals are the same it may be possible to get tougher bits onto the "stubbie box" mainshaft and if she's worth it even the larger lower front bearing .

It would at least look original !

Cheers  A .

<{POST_SNAPBACK}>

Thanks A,

I have a spare L20ET box now, picked one up at Newcastle off ebay for $125.00, plus I have the US T5 box and an R31 RB20DET box.

I might have some fun trying to destroy some gearboxes lol

SWR has my L series front housing doing the mods for it to bolt onto the RB box at present.

Cheers,

D

[works 510]

Ca18/Sr20 boxes can be used with a L series bellhousing aswell, same mods when doing the Rb20 box to L bellhousing (enlarged hole and bearing).

Ca/sr and possibly Rb20( not sure tho) are about 25mm longer than a long style datto box (Fj20 and z18et box's too).

I have a ca18det box on a L series bell here that i might sell due to not using it in my 1600.

Another tip when puttin a L bellhousing onto a other box, is too warch the selectors and make sure they dont move, if they do you will only be able to select certan gears, and this isnt much fun after youve put the box in the car...

(i know someone who did it).

Hope this is sorta on topic and can be usefull?\

Cheers...

[works 510]

Disco,

I have seen the close ratio 260z gears go into a stumpy aswell, so the possibility of whatever else nissan can fit in there too

[discopotato03]

I've got a Bluebird box kicking around here somewhere that had Stu's Aust spec 260Z/warner (brass) syncro conversion done to it . Good ratios , pity about the narrow gears and small syncro hubs .

Cheers A .