First, i am lacking in knowledge of these two motors. I’ve already gave up on my 240 project b/c of finacial issues. I just want some knowledge dropped on the good and bad on tuning these motors and which might have the best tuning potential for a shade=tree’r.
I did some research and the best i coudl come up with is the stock rb25 is only good for 250hp max on the stock hairdyer. I know jay is in the 11’s without a wild turbo, so with 2 more cyl., shouldn’t it be easier to get more juice out of an RB25? …AND then there is like issues with the rb being heavier, so u need more power and then the worse f/r weigh split…AUGHDDFFAWK! fawk me :crying: :wtcslap:
RB25 is a great motor and I have heard it is way stronger than the SR20. The SR20DET found in the S13 has been known to hold about 526whp on stock internals. Just because it handled 500+whp doesnt mean it is safe. I know of people running 400-430whp safely, but I would personally do some internal work if I didnt have a couple engines laying around for backup. The RB25 has been rumored to handle near 600whp with stock internals. Now the real question is cost when you look at engine choices. Parts for an RB25 will be more expensive than parts for an SR20 due to the limited production and importation issues. If you got the cash build an RB25 powered monster. If you are not so rich just stick with the SR20 as you can find the parts needed to get into the 400whp area for under $5k. For info on the sr20 go to www.sr20forum.com and for the RB25 you should look at 240sxforums.com.
With there being so little RB swaps in s13’s, there is no good info on this subject. Every thread in some of those sites are dumb people whoring up the thread about how to do it, not what is done after the swap. Its like once someone does the swap, they are all out of breath (and money) and call it quits. :poor:
The best i found is a few people with stock RB25’s running b/w 14.3’s and 13.8’s bone stock after the swap. Then, there are the sick people that have 30g’s in the motor and do 9’s. I have yet to find the weekend racer that is higher 300whp that is budget’d.
rb25’s are not popular because they dont have a huge aftermarket for them like the rb26’s do.the rb25’s came in the GTS skylines(the “babies” if u will) and arent very popular over in japan to mod
Originally posted by gearhead
With there being so little RB swaps in s13’s, there is no good info on this subject. Every thread in some of those sites are dumb people whoring up the thread about how to do it, not what is done after the swap. Its like once someone does the swap, they are all out of breath (and money) and call it quits. :poor:
The best i found is a few people with stock RB25’s running b/w 14.3’s and 13.8’s bone stock after the swap. Then, there are the sick people that have 30g’s in the motor and do 9’s. I have yet to find the weekend racer that is higher 300whp that is budget’d.
SR20forum is about the most reliable source for info. The 240 forums have way too many new kids and wannabe drifters. I have known people with stock DET’s in S13’s running in the 13’s.
is there anyone in the area that has an RB in a 240? There’s no way im going to put the money into an RB26…but probably after im done with the rb25, i’ll have the equivelant in an rb26 :dunno:
Originally posted by gearhead
is there anyone in the area that has an RB in a 240? There’s no way im going to put the money into an RB26…but probably after im done with the rb25, i’ll have the equivelant in an rb26 :dunno:
RB25 is for people with money to throw around. You will have something original in the end but is it really worth the price?
Originally posted by raverjames
RB25 is for people with money to throw around. You will have something original in the end but is it really worth the price?
same goes with the rb26 swap.we have 5500 bucks into the rb26 we have and the rb25 tranny needed.
think about it…how much does a b18c5 swap go for?same price.but with the rb u get double the hp and TONS more potential…
ok then…what about an s15 swap?
just drop an ls1 into it and call it a day 
on a serious note i think the rb swap is a bad ass idea… wish i would have had the money and the car to do it last year but i got stuck on a v8 :hs:
:dunno:
I think the RB25 is an impressive swap, but the SR20 swap is a well-beaten path…
rb25’s ain’t bad…all around car, the sr20 is better. with the money it’ll take to make 500 hp on an rb25, you could do the same with the sr. i dunno…they both are cool…you really wanna play, get the 26
sheesh…if only i had the greenback, then this would be so much easier! If only i had $5000 to get me started on an rb26dett!
