Jump to content
SAU Community

R31 engine swap, SR20 or RB20?

Dori
 Share

Recommended Posts

Dori Rookie

Dori

Posted
Posted

Hi guys im new on these forums (upto 2 posts i think) and im a bit of a newbie.

Anyway right now my '86 r31 has a big crack in the exhaust manifold and possibly needs a new head gasket so i was thinking about just doing an engine swap and i've narrowed it down to either an SR20DET or RB20DET.

Can anyone please tell me the ease of droping one of these into the r31, pro's and con's of both engines and some information on the two.

Dori

Link to comment
https://www.sau.com.au/forums/topic/46211-r31-engine-swap-sr20-or-rb20/
Share on other sites
Bluprint Veteran

Bluprint

Posted
Posted
Hi guys im new on these forums (upto 2 posts i think) and im a bit of a newbie.

Anyway right now my '86 r31 has a big crack in the exhaust manifold and possibly needs a new head gasket so i was thinking about just doing an engine swap and i've narrowed it down to either an SR20DET or RB20DET.

Can anyone please tell me the ease of droping one of these into the r31, pro's and con's of both engines and some information on the two.

Dori

RB20 would be easier to put in, mounting points are all the same, except for the gearbox

Both are about as capable as each other, maybe the RB20 could be taken a little further

R31 POWER Mentor

R31 POWER

Posted
Posted

As Bluprint said it all bolts in easy,R32 motor and 5speed went straight into my Oz R31 with no welding grinding,it was just like putting a Rb30e in but the RB20det looks more sexy :headspin:

Dori I gather your R31 is oz and if it is the R32 gearbox will bolt up,I'm not sure about imports thou

Plus the Rb20det sounds so much better than the SR20 :aroused:

NismoR31Jet Community Regular

NismoR31Jet

Posted
Posted

What R31 is it? Is it a pinny or a skyline?

Pinny's have different gearbox mount locations to skylines. If it is a skyline any rb engine will physically bolt straight in. The wiring is a different story.

I am not sure on the mods needed to make an rb engine fit into a pinny shell, or dropping a sr20 into an R31.

If you have a manual R31 skyline for example and you stick an sr into it, they have a 3.7 diff, and I would assume the sr has less torque then an rb? that would make it a bit of a slug down low.

Also, what do you want the car for? Daily driver? drags? or just to be different? Different would be going sr, a nice daily would have to be an rb30 turbo.

fatz Grand Master

fatz

Posted
Posted

r31 skyline

the sr20 will bolt in you just have to use the cross member from a silvia and extand the bolt holes at the front 1 inch (cost about 20 bux to do) seeing as you have used the sr20 crossmember you usethe sr20 struts and you have a far better choice of coil overs for cheap thus your car will handel better especially with the light weight

now wack in a skyline auto diff (higher ratio so lower top speed but will still get to 200 very quickly)

if your insydey come around and check mine out when its running and make the decision because it will be worrth the compare

and you wont look back from the sr20

pete

rrrr Enthusiast

rrrr

Posted
Posted

what sort of budget are u looking at?

What computer will u run the motor with? (stock ?)

will u do the conversion your self, or will u be paying a workshop to complete it?

Have u also considered selling your car and buying some thing that is already turbo? ( e.g: R31 GTX coupe, GT passage etc?) Doing a conversion may prove more time consuming, exspensive and heart breaking than u may have ever thought?

My 2 cents.......

Dori Rookie

Dori

Posted
  • Author
Posted

hey guys thanks for all the replies

sorry its taken me so long to reply but i crashed my car and have been busy tryin to get it back on the road.

just a couple things about the car for those that asked

its an Oz R31 skyline

it will be used for daily driver, drags and maybe a bit of drift further down the track

and lately i've also looked at doing a rb30de conversion

anyway any conversion done i'll be doin myself and maybe a coulpe of friends

i'll be using stock ecu's unless doing the twin cam head swap

any conversion i do i'll be using the r31 5 speed but will replace it later on ( i've just rebuilt it so will try to make the most of it)

not to sure about the budget probably 3-4 grand

umm think i've answered them all

one more thing the only problem i have with doing the rb20 swap is the lack of torque down low. are there any mods i can use to increase power in the low rev range? if i do go the rb20 that is.

anyway thanks for all the help

Cheers

NismoR31Jet Community Regular

NismoR31Jet

Posted
Posted

I would sujjest for that sort of budget just turbo the rb30, using VL turbo injectors, ecu, exhaust manifold and turbo. stick a cooler on it and about 10-12 psi and you will have a torquey and powerful R31. Talk to the boys in the R31 skyline club....A lot of them have done it with great results.

Browny_r31 Newbie

Browny_r31

Posted
Posted
that a killer conversion, nismor31jet! rb26 in a r31.....never thought itld happen

i think a few people have them now. I know three coupes do but i think thats the only 4 door (that i know of anyway)

the rb engine is soo cheap now. U can pick up a rb20det with gearbox (out of a r32) for 1650 ready to drop in

fatz Grand Master

fatz

Posted
Posted

yea i already have a rb26dett hr31 skyline

goes quite nice i must say... however just blew the turbos

budget for the sr20 conversion

4door r31 registered to august (very rough car... very rough) 1k

i already had the sr20det so for me free butyou will need a front cut so 3k

do it all yourself

there you go 4k on the road

engineer it 600 bux

4.5 k

im hoping to do it for about 2k on the road but like i said above i already had the engine

should be gravy!

putting the engine in tommorow

pete

if your in padstow come around and help out

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • GTSBoy
      What brakes on R34 GTT(Europe)

      By GTSBoy · Posted

      I would just put EBC back on the "I would not use their stuff" pile and move on.
    • Duncan
      What brakes on R34 GTT(Europe)

      By Duncan · Posted

      Can I suggest you try EBC directly again and link them to as many competitor catalogues as you can to show their listing is incorrect, eg https://dba.com.au/product/front-4000-series-hd-brake-rotor-dba42304/ If you have access to an R33 GTST VIN and your VIN, you could also use a Nissan Parts lookup like Amayama to show them the part number is different between 33 GTST and 34 GTT which may get their attention
    • Kapr
      What brakes on R34 GTT(Europe)

      By Kapr · Posted

      So i got reply from EBC and they just this site where you can clearly see those 296mm fronts on R34 GTT. I send them photos and "quotes" that 296mm are not for 34 GTT and they are too small. But it will be very hard to return them cuz nobody here knows 100% and they just copy those EBC catalogue :-D https://ebcbrakesdirect.com/automotive/nissan/skyline-r34
    • 04-LOOX
      R34 GTR Vspec Garage Sale - All must go!

      By 04-LOOX · Posted

      Hi, is the HKS  Tower Bar still available ? negotiable ? 🤔
    • Duncan
      Duncan's V37.......race car?

      By Duncan · Posted

      From there, it is really just test and assemble. Plug the adapter cables from the unit into the back of the screen, then the other side to the car harness. Don't forget all the other plugs too! Run the cables behind the unit and screw it back into place (4 screws) and you should now have 3 cables to run from the top screen to the android unit. I ran them along the DS of the other AV units in the gap between their backets and the console, and used some corrugated tubing on the sharp edges of the bracket so the wires were safe. Plug the centre console and lower screen in temporarily and turn the car to ACC, the AV should fire up as normal. Hold the back button for 3 sec and Android should appear on the top screen. You need to set the input to Aux for audio (more on that later). I put the unit under the AC duct in the centre console, with the wifi antenna on top of the AC duct near the shifter, the bluetooth antenna on the AC duct under the centre console The GPS unit on top of the DS to AC duct; they all seem to work OK there are are out of the way. Neat cable routing is a pain. For the drive recorder I mounted it near the rear view mirror and run the cable in the headlining, across the a pillar and then down the inside of the a pillar seal to the DS lower dash. From there it goes across and to one USB input for the unit. The second USB input is attached to the ECUtec OBD dongle and the 3rd goes to the USB bulkhead connected I added in the centre console. This is how the centre console looks "tidied" up Note I didn't install the provided speaker, didn't use the 2.5mm IPod in line or the piggyback loom for the Ipod or change any DIP switches; they seem to only be required if you need to use the Ipod input rather than the AUX input. That's it, install done, I'll follow up with a separate post on how the unit works, but in summary it retains all factory functions and inputs (so I still use my phone to the car for calls), reverse still works like factory etc.
×
×
  • Create New...