Official: SR vs. KA vs. CA vs. RB vs. VQ vs. LSx




Ka is not necessarily easier than the SR.

alot of people think that they can do it cheaper and end up with the same or similar power as the SR. all of these people are on at least their second engine…lol… some even more.

that is not to say that the KA-T cant be done and done well, but in order to do it you better friggin believe that it will be every bit as expensive as the SR.

they are essentially equivalent

CA is poo, budget turbo set up, if you want big power start with one of the other engines.

RB is $$$, budget $9000 just to get it in and running. pro’s are obvious

VQ / VG meh, not enough info or experience with them in 240’s to discuss.


Guess I’ll be the 1st to actually post something useful


Displacement - 1809cc
Bore - 83mm
Stroke - 83.6mm
Compression - 9.5:1(DE) 8.5:1(DET)
Horsepower - 135 HP @6400RPM(DE) 175 HP @6400RPM(DET)
Torque - 115 ft/lbs @5200(DE) 166 ft/lbs @4000(DET)


S13 (including both red and black top SRs for the 180sx)

Displacement: 1998cc (2.0 liter) DOHC 16 valve
Bore and stroke: 86mm x 86mm
Compression: 8.5 : 1
Horsepower: 205hp at 6000rpm
Torque: 203 ft/lbs at 4000rpm
Stock boost: 7 psi
Throttle body bore: 60mm
Injector size: 370cc/min
Turbo: T25
High Port Head

S14 changes:

Horsepower: 220hp at 6000rpm
Torque: 203 ft/lbs at 4800rpm
Turbo: T28
Low Port Head

S15 changes:

Horsepower: 250hp at 6000rpm
Transmission: 6 Speed, Close Ratio
Injector size: 480cc/min
Turbo: Upgraded T28

1989-1990 Nissan 240SX

Engine: KA24E - Single Over Head Cam
Displacement: 2.4L
Body Style: Hatchback/Coupe
Weight: 2684lbs

Horsepower: 140hp @ 5,600rpm or approximately 126whp (wheel horsepower) @ 5,600rpm
Torque: 152 ft-lbs @ 4,400 or approximately 146 ft-lbs wtq (wheel torque) @ 4,400rpm

Compression: 8.5:1 or 9.1:1
Cylinder Compression:
Standard: 192
Minimum: 142

1991-1998 Nissan 240SX

Engine: KA24DE - Dual Over Head Cam
Displacement: 2.4L
Body Style: Hatchback (S13 only)/Coupe

Horsepower: 155hp @ 5600rpm or 140whp (wheel horsepower) @ 5600rpm
Torque: 160 ft-lbs @ 4400rpm or 154 ft-lbs wtq @ 4400rpm.

Compression: 9.5:1
Standard: 180
Minimum: 150


No. and arrangement of cylinders = 6, in-line, vertical
Combustion chamber type = Hemi-spherical
Valve arrangement = Overhead valve type
Camshaft arrangement = Double Overhead Camshaft
Total displacement cc = 1998cc
Bore x Stroke mm = 78.0 x 69.7
Compression = 8.5:1
Bhp = 214bhp at 6600rpm at flywheel
transmission loss = 38bhp
torque = 185 lb/ft


RB Info

1. RB20DET

This motor is a common choice among RB enthusiets. It pretty cheap (cheapest of the RB’s). prices can range anywhere from about 1500(motorset) to about 2500(clip) it depends on where you get it from. its got good potential and its reliable(as are all the RB engiens). Its a 2.0L straight 6 single turbo.

RB20 specific site:

misc info:
Speed sensor will interchange with the stock KA24 sensor and your speedometer will be accurate.

You do not need custom mounts or driveshaft, the KA driveshaft and R32 crossmember work fine.
Tach can be calibrated to be correct, and the entire KA gauge cluster can be made to work.

Parts needed for Rb20swap:
RB20 front clip (makes the swap much easier to have a clip)
Fuel pump (300ZX, skyline, walbro 255, denso supra etc) you cant use KA.
radiator (KA one overheats way to quickly)
KA 5 spd driveshaft
theoretically thats all you need. there will always be more

other info:

rb20 plugs are NGK PFR5A 11

rb20 holds 4.25 quarts of oil

uses z32 n/a clutch

uses z32 oil filter

In the engine code RB20DET:

RB = engine series.

20 = displacement (2.0L)

D = DOHC (Dual Overhead Cam)

E = ECCS which stands for ‘Electronically Concentrated engine Control System.’ Basicly how the ECU uses all of the sensors to manage the engine and how it’s running.( sombody correct me on this if im wrong)

T = Single turbo

2. RB25DET

This and the RB20 are the usual choice of people who do RB swaps. the RB25 is more expensive. anywhere from 500 - 1.5k more than than the RB20. again it depends on where you get the motor/clip from. the RB25 is a 2.5L straight 6 single turbo. Its got more power than the RB20 as well as more tq.
You do not need custom mounts, the stock crossmember bolts up fine, if you re-drill it about 1" back for the motor mounts, their are no clearance problems except the hood, and the shifter is centered.

The speed sensor, you can swap the small gears off the end with the KA24 or SR20 wheels. You may also be able to use a 300zx speed sensor pinion (not verified)

You DO need a custom driveshaft.

The entire gauge cluster can be made to work accurately (same as RB20)
RB25 specific site:

RB25 parts needed for swap:
RB25 clip.
Custom driveshaft
Fuel pump.
custom tranny mount plates
again theoretically this is all you need.

Engine code RB25DET:

RB = engine series.

25 = displacement (2.5L)

D = DOHC (Dual Overhead Cam)

E = ECCS which stands for ‘Electronically Concentrated engine Control System.’ Basicly how the ECU uses all of the sensors to manage the engine and how it’s running.

T = Single turbo

3. RB26DETT aka the godzilla motor.

This is the god motor. Its used in the Skyline JGTC cars for a reason. the RB26 is basically a detuned race engine. It was actually designed for race use more than street use. It is the most cabable RB motor that rolled out of nissan. Although its sounds great, its also the most expensive. you need an RB25 transmition to use with the RB26. You can use the AWD trans that came from factory but it makes things alot more complcated. you might want to contact 180GTR on here about that. The RB26’s can run about 3500-6500(6500 as listed on mckinney’s website the highest ive ever seen). Installation is also the most difficult of the RB motors. Engine code R26DETT:

RB = engine series.

26 = displacement (2.6L)

D = DOHC (Dual Overhead Cam)

E = ECCS which stands for ‘Electronically Concentrated engine Control System.’ Basicly how the ECU uses all of the sensors to manage the engine and how it’s running.

TT = Twin Turbo

RB specific:

RB intake plenums will not interchange without an adapter plate, or new mounting points.

The RB20 and RB25 exhaust manifolds are interchangable. The RB26 has a twin setup so it is not interchangeable with the RB20 nor the RB25.

an RB26dett turbo is not better than an RB25 or RB20 turbo, it’s too small and is chosen for a twin setup.

also an A31 cefiro crossmember will mount the RB20 and 25 fine, (not sure about the 26) you may have no clearance issues at all since the Cefiro is extremely close to an S13 and comes with a RB20 stock. (not confirmed this yet)



this topic is annoying, im in the business and ill tell u the reasons i went with the sr20det…dont argue with me, cuz this is what I am saying from personal opinions…no one is right or wrong on this topic.
Im speaking for the average jo, who works, studies and loves their 240 and doesnt have 25 G a year to dump into their car.

1- for sure the least downtime no matter what…almost everyone who did ka-t took a while to get it running perfect and tuned…sr just plugs in and ure ready to go.
3- most reliable for 100% sure
4- lasts longer
5-parts are easily available
6-makes the car lighter
7- you dont loose the nimble feeling, ( rb’s fuck the light feeling of the car)

These are my opinions…any of them un true?


To my knowledge you have only been in 1 ca setup, and it did have some problems.
Don’t knock it until you really know what you are talking about. Its very comparable with the a sr with the same upgrades.
The main difference I notice is that aftermarket parts and full engine sets are usually eaiser to come by with a sr.

Ca is a great engine with turbo upgrade (even a sr t25), exhaust, and intercooler. Its a much smoother and freely revving engine.

Isn’t there some guy who owns a gas station or something around the Niagara area with an insane CA setup he imported ?

I’d reccomend a SR over a CA only because they are eaiser to get full sets , eaiser to get parts for, and its a really good engine.
If you can get a good CA setup for a good price, go for it, its a great engine aswell.


I know this is suppose to be a VS thread or for people to fight and say my SR is faster then your KAT but I posted the info above for newbies who may be reading it at the same time

I strongly believe that an SR is the cheapest bang for your buck… (#1 reason EVERYONE has one)

If I was to build a motor I will build a CA before a KA… mainly cause its built for Boost and the CA can be a shit brick house if built right

As for an RB… I have had my car inches from Luckys Cefiro and we were eyeing it out for a good 20 mins. I would never consider it cause I know as soon as I started I would regret it… I’d build my CA


i’d definately take a KA-T over CA,

i’ve been in several KA-T’s and they all had great low end torque, more than the SR and way more than the CA.

in fact, i do think that the KA-T is ALMOST as good as the SR because the engines themselves are a dime a dozen, super cheap parts etc.

the problem is that people think you can just slap a turbo on it and run 200rwhp all day long. that is not so, and varun was right, the gas mileage is worse than SR.

i can get the same mileage on my modified SR as i did on a stock KA.

having been really close to Chris’s KA build i can say that is it very fast and probably pretty reliable but you have GOT to be a guy like chris or Adam to run a KA-T in your only car.

it is far more than a plug and play scenerio. you have to be able to diagnose ALOT of minor issues and do all your own tuning and all your own installation to make it similar in costs to an SR.

it is entirely intuitive meaning you are going to have a hard time finding a mechanic capable of fixing or trouble shooting it.

i know Chris has gone through several engines, like more than 3, and you have got to be ready to do that if you go KA-T.

Luckily chris does these swaps in half a day now, if you cant, then you should go SR.


I want to compare some $ figures so I will post what I’ve spent thus far
for a basic turn key. Off the top of my head…

This will not include the essentials both system will require (fluids, vacuum hoses, wiring supplies, nuts/bolts, etc.)

Motor: $2900
Fuel pump: $100
Intercooler: $450
Intercooler piping: $500ish
Catback: N/A
BOV: $130
MAF: N/A (came with motor)
TOTAL: ~$4100

Optional items I’ve put on:
Oil relocation kit: $85
Oil cooler: $120-$150 (I forget)
Fittings for relocaiton hoses: ~$60
Gauges: ~$275 for 4 gauges
TOTAL: ~$600

So far, roughly $4700CAD for a turn-key SR setup


G, you can’t compare KA-T setups to SR setups like that.

I know people who have spent over 20Gs on their ka-ts, but I also know people who have spend like $1500 and have a reliable ka-t.

There are a lot of variables.

Bing - not everyone can work on their SR either if they have problems.

I know many people that are no longer on their first SR as well. Replacing a ka you can pay someone to do it for you and it still costs less than a new SR if you are installing it yourself.

I would say go SR if you don’t want big power, if you want big power you may as well go ka-t and start from scratch since you will need to replace a lot of parts on the SR before you get a fast SR (manifold/injectors/engine management/exaust/fmic/rad etc.)

KA-T parts are more readily available then SR parts as well.

For the price of a fast sr with a stock block, you can have a fully built ka-t block with all the same parts.


I like the CA

While it doesnt have the torque of any of the other engines discussed here, I’ll point out that it and the RB have all the features of the SR, and then some. In particular, the CA can boast:

A higher redline - they have been known to run reliably in stock form while being pushed to 8500rpm frequently. Internal mods to increase this even more are more effective on the CA than SR since it has hydraulic lifters, as opposed to the SRs rocker arms which cause valve float at high RPM.
The CA is also a “square” motor, in that bore = stroke, whereas the SR is oversquare: the stroke is longer than the bore. Square and undersquare engines will always rev higher and more smoothly than oversquare engines.

An iron block, especially important for reliable high boost applications. The CA and SR block weigh the same amount, so there is no weight savings.

In terms of power, it’s important to note that the SR has a 200cc advantage in displacement, and a bigger turbo (a .80a/r or .86a/r turbine in a T25, vs the CAs .48a/r).

The only advantages the SR has are parts availability, and a larger displacement… but those are very significant advantages.

The CA is imo overall a more versatile and durable motor, but the SR cannot be beaten as a budget motor with the potential for high power at a relatively low cost. Though a CA costs less to purchase, to make the same power as an SR will be more expensive, because of the popularity and availability of performance parts, if nothing else.


Good CA vs SR thread

CA write up


I thought SRs were square as well? 86mm x 86mm ?


CA isnt perfectly square either




If it’s worth anything, I believe Garage Paddy is using stock CA rods with Tomei 84mm pistons on their CA Silvia drag car and it is over 650hp. Some of the CA18 heads also have 8 intake ports (1 per valve) so perhaps it is the best flowing?


I’m more interested in seeing what people have spent in getting a
stable running KA-T.

Whatever it takes for them to reach that goal of running the beloved

And I guess people who are more then satisfied with slapping a turbo on
a motor and run 7-10psi all day should have no problem going KA-T.

Shit I almost read this wrong…

You must be joking…

If I was a bit more mechanically inclined and could have the luxur to put
a block on a stand and beef it up, then I would.

But I feel I can get more from the SR over time, then I can with a KA-T
with my knowledge.


Another advantage to an sr20det is that the motor is made to run hotter then the ka, and im 100% sure that if u took the average ka-t setup to the circuit and really beat on it like 70 laps in one day it would not take the abuse for as long as an sr20…im talkin like 8.5psi on both motors say, all day 8 hour event…thats where u love the sr20det cuz it takes the beating far better then a stock ka motor with 8.5psi with say a t25 would…Im sure anyone who has been to long events at shannonville will agree that daily driving doesnt really test the durability of ure turbo motor setup, its at the circuit that u push it to your limits and where heat and durability play a larfer role. Im not really referring to one track day , but over the course of a whole, summer…say you go to 15 track events 8 hours each, im sure the sr20det at 8.5psi will hold up better then a ka-t at 8.5 psi…this is the reason most people rather go with sr20 im sure…


assuming each motor has an upgraded rad? i thought sr’s with stock cooling were bad for overheating on the track


assuming each motor has an upgraded rad? i thought sr’s with stock cooling were bad for overheating on the track[/quote]

they are so are ones upgraded with a new raditator, fans, water pump, redline water wetter. on really hot days she over heats so I turn on the heater and roll down the windows–this is on a stock turbo mind you-running about 13psi. A new turbo is sure to lead to more trouble