Trust me, I searched, rb25 and sr20 questions

[Seanbonham]

I have read through the bazillion or so threads addressing this debate but i have a few other questions and none of the other threads really answered my query.

First, i can't even really find a post addressing this, but it seems that a lot of the motors coming from japan have been beaten to hell in terms of never having their oil changed. Is an rb25det LESS likely to have these problems/treatment than an sr20det cause it's a nicer car?

Anyway,

This fall i get a check for 10k on the button. I'm planning on swapping something into a 240sx, professionally, not myself (cause well, i'm not that good yet and i want AC)

Here is my goal/dilemma

It's a DD, so i need it to start, and ideally keep starting for at least...idk a year, preferably 2.

I want to hit low 12s in the 1/4 mile so that's at a minimum,

320+whp from the RB25det

or

290+whp from a RED TOP s13 SR20det (ideally 300, cause that's the magic number)

Here are my concerns/questions.

Redtop SR20det CONS/concerns:

290whp i know isn't pushing it for the sr20det stock internals IF you got a slightly bigger turbo, injectors, etc. you'd still be pushing out probably 14-17 (guessing) lbs of boost to reach that....that's a lot to ask for an engine to run everyday. IS that a lot?

SR20DET PROS:
Cheap parts, common, etc. s*** we all know, ALSO, the s13 swap is simple enough that after i had it professionally done and all the parts in place, i'm more then capable of swapping in a new block if i blow it....so that's kind of nice.


RB25DET Cons/concerns:
Little bit more invasive a swap...that's a big engine, going to have to cut the fire wall etc...If something did break in the rb25, that's harder to find, harder to fix, more expensive. Not so confident i could swap in an rb25...probably could manage i guess....but still a more expensive motor. Biggest concern is really that... If i got an rb25 and something broke...i may be a whole s*** more out of luck than if i had the s13. However, if the rb25 is a lot less likely to break...that's kind of worth the risk. Also 300lbs weight difference means it has to make about 30 more rwhp then the sr20det needs to.

RB25det Pros:
It's a skyline..(had to say it), More importantly, it's a lot closer to that goal of 320 then the redtop is. You could probably put 300rwhp down with just a few bolt ons and stockish boost. Some have argued it's more reliable. Is it?


The most important thing here is reliability! That's what i want most.

Here's the place where i'd be getting the swap done, this is literally all they do pretty much. Both swaps would be the stage 2 for either, take a look at the parts list etc., and tell me what you guys think i should do for my goals.

[SullivanRacing06]

the rb weighs 150 more then a ka

you dont cut the fire wall on this swap when you use a mount kit or a skyline cross member

rb parts have become very popular

skyline being a nicer car the a silvia? it depends on who owned the car in japan land, you ever see a kid that takes care of his geo while youll see a new bmw that the owner has never changed the oil in.... depends on the owner not the value of the car

tune, z32 maf, injectors, fmic, 255 pump, exhaust youll be at your 320 goal on the rb

i perfer rb over sr

if your not mechanically inclined then your going to pay out the butt hole for any work that needs to be preformed after the swap

290whp everyday? that not stressing the motor unless your whacking the rev limiter in every gear, i drove a 710whp s13 around everyday for three years with no problems. like i said before the motor will last if you take care of it

just my .02

[Sugar]

The shape of the motor is up in the air. Just buy from someone reputable and you shouldn't have many issue.


Both of those power goals will be cake. You are right about an RB costing you more though, the initial swap itself and the repairs. Thats the reason I went with the SR instead.

As far as the RB being more reliable with the HP. Both of those numbers are weak sauce for those engines, so you won't run into many reliability issues other than the usual. Do either swap with quality parts and you'll be fine.

[DeatschWerks]

Also, you won't be driving it around at the time at 12-14 psi unless you are just flat footing it every where you go (might do it the first week or two, but the LEOs will put you in your place. )

Like the guys above have said, if you take care of the car, you shouldn't have any issues with it as a DD.

I know it's not a Honda, but a good alarm probably wouldn't be a bad idea, either.