Gudday, Ive got a RB20 in my VL and lately have been thinking of going to a rb25. Can anyone tell me the actual differences in the engines? like is it just the head/injectors changed? or is the bore/stroke different? Also can anyone tell me if bov's are illegal in NSW? Cheers!!!!

lol well ones 2 litre and ones 2.5 Some original photos have not been recovered yet.

WOW.. that was soo helpful DriftArab Ill think youll find that the bore and stroke is different! haha osrry i didnt help much either! Some original photos have not been recovered yet.

wouldnt be just a head swap, compression 9:1 in Rb25det 8.5 in Rb20det bore and stroke 86 X 71.7 in Rb25det 78 X 69.7 in Rb20det of course more power with the Rb25det.

www.rbforums.com (http://www.rbforums.com) These guys have got info on EVERY RB series motor produced by Nissan.

have you thought about stroking the rb20 to a rb22 or rb24? figures on paper make a rb24 look better than a rb25 or 26... but it all depends on how much money u want to spend

haha, sorry. a stroked RB20 "looks better" than a 26? how do you figure that one out?

Wouldn't a stroked rb20 cost more than the rb25? You have to source the crank from a rb25 then you have to fit it.

the figures on paper looked better.. i think it somehow worked out with a little more torque...

Stroker kits for RB20's are worth more than an RB25 is itself. With the money saved you could probably throw in some cams and a hi-flowed turbo. That'd look better on paper than a stroked RB20, believe me.

the stroker kits will spool the turbo faster as the exhaust displacement is greater... then why would people stroke a rb26 to rb28 than buy a rb30 and make it a rb31?

I'm guessing because a rb28 would still like to rev hard, (not quite as hard as a 26). Power = Torque * RPM A stroker kit for a RB26 doesn't come cheap, and are designed to handle lots of power (i.e. it's the whole kit and caboodle (pistons, rods, crank etc etc)). A RB30 bottom end is dead set primitive in comparison.

[ PHP Code: QUOTE=sp00nfed]I'm guessing because a rb28 would still like to rev hard, (not quite as hard as a 26). Power = Torque * RPM A stroker kit for a RB26 doesn't come cheap, and are designed to handle lots of power (i.e. it's the whole kit and caboodle (pistons, rods, crank etc etc)). A RB30 bottom end is dead set primitive in comparison.[/QUOTE] I think it might rev harder harder.

Quote: Originally Posted by calais25t WTF as if it wont rev harder use ur ****en brain. By changing the bore/stroke of an engine you change it's character, a RB28 would have more torque but would be unable to rev as high as a RB26. Please kindly grow up. Thanks.

By changing crank conrods pistons etc ur obviously going to change valve springs bearings other internals etc wich in turn will enable the engine to rev higher than standard.

it all comes down to piston speed and how much your rods can take

Quote: Originally Posted by duz360 it all comes down to piston speed and how much your rods can take Yeah that's pretty much it. Typically engines with a longer stroke than bore don't rev as high as those with a larger bore than stroke. A really good example is the 2003 model s2000 compared to the 2004 model. Honda s2000 spec's (2003->2004 model) (http://www.hondanews.com/CatID2069?mid=2003100141254&mime=asc)