Jump to content
SAU Community

Recommended Posts

WTF? RB25DET's are factory 9:1 comp ratio

You are gaining nothing by putting RB26 gear in your RB25 block. Unless you have a spare crank lying around that you need to use. The stroke is slightly more but the extra 100cc is not going to do FA for torque or power.

The reason I will use rb26 crank is because I have the block and enginehead but no crank,rods or pistons. So instead of buy an rb25 crank and then mount a crank collar on it would cost almost as much as an longnose rb26 crank. If 100cc doesn´t do anything then I wonder why so many high performance gt-rs from japan is stroked to 2,7?

Almost every aftermarkets pistons for rb26 is 8.5:1 but If the rb25 head is smaller cc maybe it is possible to get 9,0:1 then :)

^ umm but how do you have a RB25 now, without any innards?

It's not even 100c, its like 60 or something.

9:1 will be fine, pretty standard for anyone rebuilding in this day an age considering fuel advancements over the past 10 years+

Also just use GTR rods, they are fine for over 400rwkw and less than half the price of eagles

^ umm but how do you have a RB25 now, without any innards?

It's not even 100c, its like 60 or something.

9:1 will be fine, pretty standard for anyone rebuilding in this day an age considering fuel advancements over the past 10 years+

Also just use GTR rods, they are fine for over 400rwkw and less than half the price of eagles

I bought a head cheap for about 1 year ago. The I found a block now to. So I will use them to build a complete engine of. A std rb25det cost about 2300Aud here and Im gonna change so much anyway so I think this would be the best way to go :)

You can buy a RB25 bottom end for next to nothing my friend... the head is the most expensive part.

Then just GTR rods ontop of that and you are set. Would be less than $1000 AUD easily. Not sure there you get 2300 from when you already have the top end :)

Beats buying a new RB26 crank IMO, unless you know the RB26 crank you are getting is fine but the cost to check, and if it needs repairing then its almost neutral.

You can buy a RB25 bottom end for next to nothing my friend... the head is the most expensive part.

Then just GTR rods ontop of that and you are set. Would be less than $1000 AUD easily. Not sure there you get 2300 from when you already have the top end :)

Beats buying a new RB26 crank IMO, unless you know the RB26 crank you are getting is fine but the cost to check, and if it needs repairing then its almost neutral.

Im from Sweden and It´s alot more expensive with parts here. I have searched for a while for a bottom but didn´t find someting we don´t have so many parts here. So I had to order the block from England. I want the long oilpumpdrive to so I think the rb26 crank would be fine.

Edited by Turbo_Knuff
Im from Sweden and It´s alot more expensive with parts here. I have searched for a while for a bottom but didn´t find someting we don´t have so many parts here. So I had to order the block from England. I want the long oilpumpdrive to so I think the rb26 crank would be fine.

The collar can be purchased and fitted for about $200 total. Being in Sweden might make things hard but there's always international shipping

Don't think that getting a second hand rb26 long nose crank is the best solution, because IMO it's not.

Often times on a second hand crank you will see where the oil pump drive has rounded away on the edges of the flat even on the long nose. A collar with international shipping will be under $100AU easily, and then you know the drive is 100% OK after fitting.

Edited by James_03
DO NOT shave the head more than just a surface because it'll stuff up your cam timing and possibly make the timing belt go slack.

Just order some custom 9.2:1 pistons. You won't be disappointed!

Sorry but that's the biggest load of shit I have ever heard. You aren't going to take enough off a cylinder head to have that much of an effect on the timing belt.

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...