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If your after 224rwkw roughly i'd just rebuild the RB20 (if it's clapped out) and make it as reliable as possilbe. It can make that power without much stress. My mate is making 210rwkw in his R32 and his engine is dead stock with a decent turbo and support mods. If he rebuilt the motor (i told him to, as opposed to going an RB25 :D ) and got the head ported it would be seeing close to 250kw methinks and be tight, responsive and would last quite a while.

I reckon the extra CC's in the 25 and 26 make them better for the street because of the extra torque and generally quicker boost (depends on turbo size of course). I went on a crusie with three R32's recently and they don't make full boost till about 5000rpm. I easily pull away from them with my stock turbo RB25 until they're doing about 6500rpm and making FULL power :D .

So uprated cams and cam gears with a rebuild will help that, meaning all of this stuff done to your RB20 make it into a weapon.

So don't bother with the conversion if your not DETERMINED to go an RB26. Make what you have work.

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I reckon the extra CC's in the 25 and 26 make them better for the street because of the extra torque and generally quicker boost (depends on turbo size of course). I went on a crusie with three R32's recently and they don't make full boost till about 5000rpm. I easily pull away from them with my stock turbo RB25 until they're doing about 6500rpm and making FULL power :D .

So don't bother with the conversion if your not DETERMINED to go an RB26. Make what you have work.

fair statement with the extra cc's, but full boost at 5 grand? how big were the turbos they were running? would have to be something around the td06(10cm housing), gt30 range surely.

fair statement with the extra cc's, but full boost at 5 grand? how big were the turbos they were running? would have to be something around the td06(10cm housing), gt30 range surely.

I know it's shocking lag. One dude had a KKR something and is about double the size of factory (it nearly touches the strut tower). Another had a highflow which was bored out to the point of the workshop saying "don't bolt it up too tight, you'll warp the housing" :cheers:

They go hard but RB20's need a bit of help if you put it up against the RB25+26. Cams and porting ftw.

They go hard but RB20's need a bit of help if you put it up against the RB25+26. Cams and porting ftw.

Down low they do suffer. But i would like to add be careful with advice like head work and cams for helping RB20s. Unless of course you can site specific examples where it was worked. Personally from what i have done personally to my car and what other RB2o ownershave done....cams dont automatically do anything for an RB20. Certainly dont make them automatically responsive, certainly dont make them automatically allow them to make more power up top. As for porting, that can slow velocity at low rpm which hurts cylinder filling which will hurt gas velocity and turbo response.

So just be careful if posting absolutes as people can end up wasting lots of money.

The RB20 is a short stroke small discplacement 6 cylinder engine. It will never make great power down low. If you cant live with that then either sell the car or go transplant. If you dont mind waiting a tad for the power, or happy to drive around it...then they can deliver the sort of ols school power that makes you smile ear to ear :D Cheaply and reliably :D

tell em the price son, the price son.

Roy boys 250rwkw RB20 cost him $400 from the wreckers.

he then bolted his TD06, intercooler, injectors, PFC and a throat full of boost.

almost makes enough power to travel back in time to root his future mum.

Edited by GTST
Down low they do suffer. But i would like to add be careful with advice like head work and cams for helping RB20s. Unless of course you can site specific examples where it was worked. Personally from what i have done personally to my car and what other RB2o ownershave done....cams dont automatically do anything for an RB20. Certainly dont make them automatically responsive, certainly dont make them automatically allow them to make more power up top. As for porting, that can slow velocity at low rpm which hurts cylinder filling which will hurt gas velocity and turbo response.

So just be careful if posting absolutes as people can end up wasting lots of money.

The RB20 is a short stroke small discplacement 6 cylinder engine. It will never make great power down low. If you cant live with that then either sell the car or go transplant. If you dont mind waiting a tad for the power, or happy to drive around it...then they can deliver the sort of ols school power that makes you smile ear to ear :) Cheaply and reliably :banana:

What i say isn't absolute or expert opinion, it's my opinion. If anyone takes advice from someone on the forum and spends thousands without asking a workshop to verify are plain stupid :banana:

I agree that cams and porting don't gaurantee an awesome responsive motor. I'm talking from the perspective of RB20 Vs. RB26. If we're talking RB20 left stock to RB20 with head work then of course the stock with have better response but be more restrictive up top.

I can give an example of this work being done, and it backs up what you were saying. One of the dudes on the drive i went on had about 245rwkw on his RB20 with a pair of cams on the head. He said it made a big improvement. Another R32 had a totally stock engine but a slightly bigger turbo. Redlining third gear side-by-side the R32 with cams couldn't pull away (as you'd expect earlier power). Approaching redline the stock motor R32 began to edge away as the turbo on the cam'ed RB20 ran out of puff.

Saw that with my own eyes.

Either the guy was BSing about the amount of power he made or cams don't really do much unless the setup is real special ;)

So as i said, blow for blow a stock RB20 is a good thing for the street if you want response, versus a worked RB20 which might just gain lag from low RPM. But comparing it to an RB26 it will suffer BOTH down low and up top.

almost makes enough power to travel back in time to root his future mum.

:P

Edited by R338OY
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