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Discussion Starter #1
if you were to swap an rb25det into an s13, just a barebones swap, what kind of quartermile would you put down?

I am trying to determine if it would be better to swap an sr20 and upgrade the turbo or put in an rb25.

also what would an rb26 run? I dont plan on attempting this, but am just curious what an rb26 s13 would run
 

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mine ran s13 hatch [email protected] "stock"

mostly just the mods i needed for the swap, i still consider this pretty stock

FMIC
Nismo FPR
Walbro 255
intake cone filter
power fc (tuned with datalogit), 268whp on 90 octane
blitz ebc (12 psi)
3" downpipe/exhaust/N1 muffler
competition clutch

open diff and some drag radials i took off my civic (kinda small)

ive seen faster. ive seen slower. kinda depends on what you do to it too when u swap it. IMO the potential to go faster is higher with RB's over SRs. but SRs will be much cheaper.
 

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i dont know what stock sr runs. i assume they run low 14's. i mean, they only come with what 205hp right? the diff and tire setup matter too. im sure if i had lsd and some better tires i would have hit a high 12
 

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ka24det ftw

but in either scenerio i like power to weight ratio's... but if your only worried about going straight rb i guess...
 

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Engine size doesnt really matter much. It all boils down to HP and Weight. A 250hp KA, 250hp RB, and 250hp SR will all do about the same trap speed. Its just the bigger engine usually has more low end tq to get out of the hole faster for a quicker ET.
 

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Word. Power under the curve for the win. Literally.
 

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Discussion Starter #9
yeah I plan on going straight. I would like to retain the ability to go around corners and such but mostly I plan on straight line racing.

so is that the concensus then? low 13's?
 

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low 13's sounds about right to me.
 

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Discussion Starter #11
well I plan on doing this over the summer and money is not really an issue,


if some of you were going to do this, what would your list of mods be? I am looking for mid 11's. '

I am not interested in nitrious at all. and it will no be my daily driver but I dont want it to be a track only car. I want to retain PS.
 

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for mid 11's you'll probably wanna be pushing almost 400 probably about 375. For that the RB25 should be able to do it without any mods to the internals. As with any swap, I would change out the oil pump, water pump, thermostat, timing belt, and any gaskets/hoses you can, spark plugs, and fuel filter. Then for that I would change out the HG just with another OEM HG no need for cometic. While you're at it since money isn't an issue I would get ARP head studs just for extra security. I would also use the R33 X member with Syko mounts as I've heard good things about them. Then from there basic FMIC, exhaust, downpipe, intake, greddy intake if you want not necessary though. Then i'm not to turbo knowledgable but I would think a T3/T4 would be capable of this, but I'm sure someone else more knowledgeable will be able to answer that. Then you'll need tuning and injectors. If anyone can think of anything else please correct/add as needed. Thats what I could think of off the top of my head.
 

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im hoping to get to mid-high 11s on my new setup. upgraded 650cc, t3/to43, ISIS freddy intake manifold, q45 tb, z32 maf new tune, vlsd and some 275 drag radials. but i need to get the damn thing running first before i can do anything
 

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im hoping to get to mid-high 11s around 400whp on my new setup. upgraded 650cc, t3/to4e, ISIS freddy intake manifold, q45 tb, z32 maf new tune, vlsd and some 275 drag radials. but i need to get the damn thing running first before i can do anything. dunno why i edited and my first post is still there
 

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rb25det

if anyone says you will run the same times on sr20 rb25 rb20 rb26 its not true. to save you time you will add about 180 lbs with rb motors vs sr20 when it come down to it s 6cyl vs 4cyl cost more to beef up a 6 cyl than a 4cyl but a 6cyl should more reliably then a 4cyl its up to you just remember the 1/4 time comes down to weight vs hp
1/4 Mile Calculator

good luck
here is some info check it out i think it will help
SYKO Services Page
 

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180lbs isnt much at all. Thats roughly .2 of a second and maybe 1mph. Driver is gonna make more of a difference than anything else. I have both SR and RB25 and the RB pulls out of the hole alot faster than the SR because of its amount of tq from being a larger engine. TQ is really what makes for quick ET times. HP makes up the MPH. Calculations isnt everything. Go to the track and youll see why a 350hp 350c.i. v8 in a 3000+lb muscle car will own a 350hp SR20 or RB25. TQ will put the muscle car so far ahead from the start, even though he wont trap as high from his weight, his ET will be far better. The trick to going fast is to make as much tq as possible in a light chasis and make your gearing around the speed and power of the engine.
 

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180lbs isnt much at all. Thats roughly .2 of a second and maybe 1mph. Driver is gonna make more of a difference than anything else. I have both SR and RB25 and the RB pulls out of the hole alot faster than the SR because of its amount of tq from being a larger engine. TQ is really what makes for quick ET times. HP makes up the MPH. Calculations isnt everything. Go to the track and youll see why a 350hp 350c.i. v8 in a 3000+lb muscle car will own a 350hp SR20 or RB25. TQ will put the muscle car so far ahead from the start, even though he wont trap as high from his weight, his ET will be far better. The trick to going fast is to make as much tq as possible in a light chasis and make your gearing around the speed and power of the engine.
:1bowdown
 

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Go to the track and you'll see why a 350hp 350c.i. v8 in a 3000+lb muscle car will own a 350hp SR20 or RB25. TQ will put the muscle car so far ahead from the start, even though he wont trap as high from his weight, his ET will be far better.
Quoted for greatness and honesty! :thumbsup
 

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Thanks man. It really takes alot of work to run low et's with a small engine. Best i could do with my SR20 was a 10.9 @ 129mph using my G tech meter. It was never consistent enough though. It could have been so much quicker with an automatic but then it would have been laggier unless using nitrous to get the boost up so it gets off the convertor. V8's dont have that problem either.
 

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Thanks man. It really takes alot of work to run low et's with a small engine. Best i could do with my SR20 was a 10.9 @ 129mph using my G tech meter. It was never consistent enough though. It could have been so much quicker with an automatic but then it would have been laggier unless using nitrous to get the boost up so it gets off the convertor. V8's dont have that problem either.
10.9 for any street car is quite impressive. V8s have the lag problem just like I4s, it seems to me like the I4 guys use pretty big turbos compared to the V8 guys.

V8 guys also have the problem of fitting everything under the hood!
 
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