Jump to content
SAU Community

Recommended Posts

Ok so my RB20 went pop due to blow by shortly after i finished having it tuned.

Now im stuck in two mind sets at the moment, ai was going to build a RB25 HYBRID but i want to get out of this for a little less that what that would cost me.

So i was thinking of just rebuilding the 20 with forgies or looking into a 23/24 kit for it.

I haven't had much luck on finding a 23/24 kit in Australia at all and i realise that i would just have to source the parts myself.

Becuase of this im steering more towards the forged 20 with my current running gear and a few extra's.

My current set up was as follows:

Rb20 stock

TD-06 20g high mount

custom 3.25" dump into standard cat back

GReddy external gate

Turbotech boost control (14psi)

stock injectors (did have additional injector in intake plenum) and stock AFM

it was making just over 203rwk's on 14psi

Now i know that everyone will just say buy another 20 and stick in it, they are cheap and you get warranty.

Well that is true but we are building this up as one of our promo cars and want it to be able to handle the punishment its going to cop :P

Any suggestions would be much appreactiated as well as best place to go through for a rebuild kit.

Cheers GMB

DrifTas

Link to comment
https://www.sau.com.au/forums/topic/140104-after-some-help-with-rb20-rebuild/
Share on other sites

i'm guessing the ecu is an aftermarket one and the fuel pump is a stocker.

upgrading the fuel system with a better pump, regulator and injectors would be a good idea to make sure the engine has good fuel supply when pushing over 200rwkw because thats about where the stock rb20 fuel system starts to run out.

i just rebuilt my rb20 with forged pistons, i cant remember exactly what everything cost but i'v got a fair idea.

arias forged pistons 20thou up $1100

machining of the block to suit pistons $550

genuine bearings $250

genuine head gasket $150

genuine head studs $100

aftermarket manifold gaskets etc. ~$60

labor for assembly of engine $150, that was only for the bottom end i put the rest together myself.

that seems like a lot but at least you'll have a fresh bottom end that will withstand the mid 200rwkw mark with a bit of abuse.

Aaron

i'm guessing the ecu is an aftermarket one and the fuel pump is a stocker.

upgrading the fuel system with a better pump, regulator and injectors would be a good idea to make sure the engine has good fuel supply when pushing over 200rwkw because thats about where the stock rb20 fuel system starts to run out.

i just rebuilt my rb20 with forged pistons, i cant remember exactly what everything cost but i'v got a fair idea.

arias forged pistons 20thou up $1100

machining of the block to suit pistons $550

genuine bearings $250

genuine head gasket $150

genuine head studs $100

aftermarket manifold gaskets etc. ~$60

labor for assembly of engine $150, that was only for the bottom end i put the rest together myself.

that seems like a lot but at least you'll have a fresh bottom end that will withstand the mid 200rwkw mark with a bit of abuse.

Aaron

Running a GTR pump and it was getting plenty of fuel hence why we did away with the extra injector.

Running a rechipped stock 32 ECU :)

Cheers GMB

2.4 Stroker :)

I'd love to go a 2.4 stroker but the costs involved just dont really warrant the outlay.

If i was going to spend that much i would go with the 25 as a starting point instead!!!

PLUS i cant find anyone that stock/sell a 2.4 kit or info on what exactly is involved (general knowledge but not 100%) so that was another reason why i wasn't leaning towards the 2.4 :)

Cheers GMB

im currently at the same situation your at grandmasterb except my 200rwk rb20 is only just holding together. i nearly went for another second hand motor but thought why not go better if spending some cash.. im after around 220-240rwkw...

i've been askin around for options on the 2.4 and what i have been advised from a reputable tuning shop in perth is a GTR crank with forged toyota 4agze pistions. i think he also mentioned using rb25 or 26 rods aswell for their strength.. bit of machining and u got a 2.4L (please feel free to correct me anyone)

but is it worth it if a strengthened 2.0L can make 240rwkw as dobz mentioned... what turbo setups are advised for this kind of power?

as the little gt2510 has no chance....

i

From my knowledge only tomei sell an Rb24 kit and it isnt cheap. Nor is going about it on your lonesome and sourcing all the parts and the required machining hence why its a very rare excercise down here.

The 2.3/2.4 capacity is obtained by a combination of an increase in stroke from a 25 or 26 crank and larger bore from oversized pistons.

As you are planning on using forged pistons with the build, you could meet the 24 idea halfway and not use a different crank but use the oversized pistons and have a 2.1-2.2 litre. How far you can go will depend on how much meat is left and how straight the bores are. This will add to the cost of the pistons though and will only have the engine being 5%-10% larger in displacement.

So in theory, at the rpm where the turbo made maximum boost previously, you could subtract 5-10% of that rpm and assume thats where the new max boost rpm would lie.

i.e if it made max boost before at 4,000rpm, with a 2.2 litre it would be in at 3600rpm.

All that extra money and mucking around for 400rpm? Is it worth it? A decent boost controller and well matched BB turbo could yield the same if not better results on the stocker.

Food for thought. Do a search if you want any more RB24 info.

Another thing to consider iof you are rebuilding the Rb20 is what boost are you realistically going to run, and what fuel you have available to you.

Looking at the RB25DET, if i was rebuilding an RB20 wth forged pistons i woul dbe tempted to bump compression to close to, or maybe even 9.0:1

Another thing to consider iof you are rebuilding the Rb20 is what boost are you realistically going to run, and what fuel you have available to you.

Looking at the RB25DET, if i was rebuilding an RB20 wth forged pistons i woul dbe tempted to bump compression to close to, or maybe even 9.0:1

Boost wise i wouldn't be looking to run more than 1.2/3bar but seeing as the car is a daily driver it would only be about a bar.

It would be tuned on BP Ulitimate 98.

As for dropping the compression ratio i take it you mean with a metal head gasket Roy???

Cheers GMB

did you mean raise the compression roy? in doing this would u expect boost to come on a little earlier?? or is this only changed buy the size of the engine?? raising the compression on a rb20 would be good because u woulnt have to run as higher boost to make the power u want.. leigh

did you mean raise the compression roy? in doing this would u expect boost to come on a little earlier?? or is this only changed buy the size of the engine?? raising the compression on a rb20 would be good because u woulnt have to run as higher boost to make the power u want.. leigh
Yeh, was suggesting increasing the compression ratio a little.

:( sorry guys read that last one in a hurry and same with my post.

It is a pretty valid point though Roy and also something i guess i should consider!!!

Looks like i may of found a 26 crank ;)

I just wish teh RB family of heads didnt suck so bad...though i guess they are now 15 years old :devil:

The new Golf 2L has 10.5:1 compression, the things are little rockets and with chip, IC etc can still run 10-12psi. I would hope a cleaned up RB20 head could run 9.0:1 compression, though you would want to be sure that you have good inlet temps and fuel quality

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


  • Similar Content

  • Latest Posts

    • Hi, is the HKS  Tower Bar still available ? negotiable ? 🤔
    • 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.
    • Place the new daughterboard in the case and mount it using the 3 small black rivets provided, and reconnect the 3 factory ribbon cables to the new board Then, use the 3 piggyback cables from the daughterboard into the factory board on top (there are stand offs in the case to keep them apart. and remember to reconnect the antenna and rear cover fan wires. 1 screw to hold the motherboard in place. Before closing the case, make a hole in the sticker covering a hole in the case and run the cable for the android unit into the plug there. The video forgot this step, so did I, so will you probably. Then redo the 4 screws on back, 2 each top and bottom, 3 each side and put the 2 brackets back on.....all ready to go and not that tricky really.      
    • Onto the android unit. You need to remove the top screen because there is a daughterboard to put inside the case. Each side vent pops out from clips; start at the bottom and carefully remove upwards (use a trim remover tool to avoid breaking anything). Then the lower screen and controls come out, 4 screws, a couple of clips (including 3 flimsy ones at the top) and 3 plugs on the rear. Then the upper screen, 4 screws and a bunch of plugs and she is out. From there, remove the mounting brackets (2 screws each), 4 screws on the rear, 2 screws top and bottom and 3 screws holding in the small plates on each side. When you remove the back cover (tight fit), watch out for the power cable for the fan, I removed it so I could put the back aside. The mainboard is held in by 1 screw in the middle, 1 aerial at the top and 3 ribbon cables. If you've ever done any laptop stuff the ribbon cables are OK to work with, just pop up the retainer and they slide out. If you are not familiar just grab a 12 year old from an iphone factory, they will know how it works The case should now look like this:
    • Switching the console was tricky. First there were 6 screws to remove, and also the little adapter loom and its screws had to come out. Also don't forget to remove the 2 screws holding the central locking receiver. Then there are 4 clips on either side....these were very tight in this case and needed careful persuading with a long flat screw driver....some force required but not enough to break them...this was probably the fiddliest part of the whole job. In my case I needed both the wiring loom and the central locking receiver module to swap across to the new one. That was it for the console, so "assembly is the reverse of disassembly"
×
×
  • Create New...