rb25 Turbo onto rb20, does this need new ECU?

[jazza08]

Hey peeps

Seen alot of people post different views on this so i want some confirmation!

I bought an rb25 turbo and plan to hi-flow it, can i then put this straight onto the rb20 and it will run ok?

Or will i need a new afc, ecu and injectors?

The car has 3' exhaust, fmic, fuel pressure regulator (to be put on) and electronic boost controller set to 0.6 bar and 1 bar.

What parts will i need to change, what would i need to do to get the car running well with it on? Obviously if i boost past 1 bar ill need new injectors/afm to make higher power im well aware of that! More curious to know if it will run fine on 1 bar with the hi-flowed rb25 turbo...

Help would be much appreciated as this is something im looking to do in the future

Thanks

[sproosy]

the RB25 turbo should just bolt straight on dude.

[jazza08]

I know it will physically bolt straight on, even to the current dump pipe but does it need any of these other bits? Seems like if it did might aswell be better off spending abit more on a bigger HKS turbo thats all, and obviously id have to wait a fair bit longer to get a new turbo done if it needed a new ecu etc!!

[sproosy]

No you dont need a new ecu or afm or injectors. If you want to run heaps more boost you will need to upgrade those items because the injectors will probably max out and so will you afm.

[jazza08]

thats what i thought and hoped...

clarification from some members wud be appreciated, especially ones who've done it b4!

[inissane]

havent done it but am looking to do so, I would think injectors/afm/ecu fine for rb25det turbo upgrade but for a high flow depending on the output would need these three done. Also fuel pressure reg prob not much good unless ur injectors are maxing with rb25 turbo (non high flowed).

im not sure of a few other things though:

in terms of bolting her on i guess 2 new exhaust/dump gaskets and apply maniseal apparently?? Also is there torque settings that you have to use on these bolts on the t3 flange and to dump? Or do you just have a beer and a ciggy and get the spanner n im making too much fuss??

People also seem to say use the rb20 wastegate actuator cause it holds 9psi as opposed to 7psi for the rb25 one - how does this relate to your boost controller say an electronic one?

Sorry for the hijack but hope u and others would also be interested, and we get some details from dudes datve dunnit do deir durbos...didnt mean that it just evolved...ok i shut up now :Oops:

[Butters]

With a 25 turbo on a 20 they do get really fuelly. Even at standard boost levels, higher boost it gest worse.

It will work fine but not be ideal.

Say good by to "any" economy you had. Also you will obviously not make the full power potental of the turbo until its tuned. This has been my experiences anyhow

[Acidik]

If your gonna run any sorta boost thru the standard rb25 or highflowed one i would be looking at upgrading ur fuel pump!

[jazza08]

Thanks peeps

The more input the better..

[predator]

You will want tuning potential, otherwise you are probably throttling whatever gains you might otherwise get by putting it on by the stock ecu. Do it the whole way

[jazza08]

the ECU will be remapped afterwards Just wasnt sure if i needed awhole new one!

[race_snooze]

wont the stock ecu retard timing if you push it over 8psi or is that just the r33

[jazza08]

thats just the shithouse r33... lol nah i still love em

R33 ecu retards the timing at around 12-13psi i believe