Thread: S14 with SR20 or KA24

I'm from North America, but I frequent the Skyline forums a lot. This Dyno Graph along with the guy running 10's on stock long block are enough for me to see the potential of this over looked motor.

The RB20 motor is a great but I would not take it over a KA24DE.

The KA24DE can be had for $400 or less. The parts are easier to come by for the KA24DE. The parts are cheaper for the KA24DE. The KA24DE will make more horse power, more torque and do so at way less boost than the RB20 motor.

The RB20s weight is more than the KA24DE. It will cause the car to be nose heavy. It will make the car handle bad which can be fixed but the cost goes up even more. Then you got to add in the cost of fabricating the parts to put the motor in the car.

The guys here in Miami generally make 500 WHP and 500 Ft Lb Torque at 19-21 PSI. Alot of them do so on stock bottom ends with upgraded headbolts and headgasket. These cars are driven around the street on a daily.

LanceSR20s friend Andre makes 700 WHP and 680 Lb Ft Torque at 32 PSI if I remember corectly.

He has
KA24DET
Metal Headgasket
ARP Headbolts
Rods
Pistons
JWT cams
Cam gears
Turbo manifold
GT40 turbo
Tial 44mm wastgate

I will be building a rear drive 240sx at the end of 2009 and this is the way I am going.

Classic train of thought based of assumptions. I can tell You like the KA vs me who doesn't like the KA motor. This is where it boils down personal choice yet again. I love my RB when I 1st did the swap back in 05 and still love it now. I can tell you from my experience that the RB 20 handled the same as the KA S13 (like crap)except I had more power and a smoother pulling motor. If TQ was my goal I'd shoot for a VH45 n/a with bolt on a tuned ecu. That's a low 12 second high 11 second combo. I Don't like the idea of cross breading engine platforms so I couldn't dream of a LS1 in my 240. It's a cool ass swap but not for me. http://www.3rdgearvtec.net/Andys%20Videos/Dynos/S14LS1.wmv

^^^ yeah the rb20 is a totally different kettle of fish to the ka24. I wont comment on the weight as i do not know how much the ka's weight, but think they are a cast iron block?

I can talk about the rb vs sr though, and the sr WILL handle better than the rb not only because of the weight but because of where the weight is located...futher over the front wheels. To get the rb20 to handle well you need to play around with spring weights and modify the car a bit. There is a reason the sr20 is the most popular drift engine.

also blue240 if you s13 is handling like crap what mods are done to it? swaybars, cradle bushes and coilovers work wonders on the s13

Whatever motor you place into your car is personal opinion. That still just change the fact that the KA24DET > RB20DET and SR20DET

This thread was about KA vs SR. From What I have seen in my dealings with motors the KA24DE-T is the better build.

As far as KA24DE-T Vs RB20DET, the KA is far superior in every way when it comes to HP and Torque. That is not an opinion that is fact.

An RB20 motor has 2 more cylinder that hang about 12 inches further forward than the KA24 motor. The RB20 is alot heavier than the KA24 so not only is it heavier it put more weight further forward of the front wheels, this is fact. An RB throws off the handling of the car which is fact. I have driven in and have drove many of these cars and I know for a fact an RB motor handles like crap unless the proper spring rates are put onto the car.

Find me a RB20DET at 30 PSI with 600 WHP ( wont happen ) and it will have about 450 LB Ft Torque. I can find you a few KA24DET at 700 WHP with 700 Lb Ft Torque at 30-33 PSI.

Personal preferance aside an RB20DET does not hold a candle to a KA24DET.

With the advent of the VVL head the SR22VET would kill a KA24DET but cost is the problem and the price diffrence is huge. Even building a KA24DE-T vs a SR20DET to make 600-700 WHP the price diffrence favors the KA24DET buy alot.

you cant compare the rb20 vs ka24 they are two completly different engines designed for different purposes. The ka24 was designed for a nissan small truck, this is the reason it makes better torque. The rb20 was designed as a smooth high revving sports car engine designed for the r31 group A race car, and actually took home many trophies.

so to say the ka is superior to the rb because it makes more torque on a dyno is just not fact!



I dont think you can say the ka is better than the sr20 cause a few dyno's have been posted either, the sr20 has dominated drag time numbers, drifting event, and even done well in circuit cars all over the world.....


Show me a a ka24 running 7.2 sec quarters
show me a ka that has won a world class drift championship
Show me a ka thats done remotely well in a circuit event

Just pretend for a second that he said the KA is superior to the RB because it makes more power on a dyno. That doesn't make it more superior? If we can't use power output as a gross gauge for engine performance, wtf else can we use?

Just because an engine doesn't get raced doesn't mean it's not any good [for racing].

pfft there is a reason it doesnt get raced!!!!!

Once again, that doesn't mean it's not any good [for racing]. Unless the reason is that "it's not any good for racing".