671_rx7

well wazzup fellas im just wondering if any of you guys here did a KA swap into a rx7?if its ok with you guys can i see some pics of the swap? i know that the motor is going to be off 1 1/2 inch to the passenger side and you have to cut the crossmember thats basically i know about this swap..so if anyone has any other info on this swap please fill free to post your comments thankz alot jimz!

J-Rat

iTrader: (2)

please sell your car now..

iceblue

Timpo

don't do it...

KA24 is way too heavy, approx 130lbs heavier than 5.7L V8 LS1. no joke.
I heard people usally lose 130lb when they swap an LS1 into their 240SX.

driftking777

iTrader: (1)

^^^yup hes right, you'll gain alittle weight. but dont alot of V8 swappers that went iron block talk about how there handling was either effected in a good way, or didnt change it at all?

Anywho...dont go KA...its stupid

DriftDreamzSS

iTrader: (4)

haha, ka's rule, ive been trying to blow mine up for 3 years and she keeps running strong.

Whizbang

for the moeny i would opt for the 4.0L toyota V8. which i might do in a spare FB i have for the hell of it.

peejay

That's because they are too weak to hurt themselves.

iceblue

n00b, silence!

Nihilanthic

http://www.ka-t.org/

Use a button recently, idiots?

dopefishlives

The KA is a great motor -- just all the SR faboi's who scream "OMG, who'd want a truck motor?!"
LT*/LS*/Ford Mod./Etc, are all offered in trucks as well.

Truth of the matter is, a KA with the stock SR turbo, SR injectors and SR fuel pump will generate more HP than the SR at the same boost levels. Three differant guys have shown dyno's of their KA24DE-T's built from the SR parts bin and their WHP is sitting at 200-220 while the WHP of the SR is closer to 170-180. The KA internals: block, crank, rods, and pistons have been safely capable of 400rwhp, beyond that point, upgraded rods and pistons are recommended. The stock SR bottom-end is usually out of the safety margins beyond 350rwhp.

That said, I think a KA-powered RX-7 would be a poor idea. I personally think that piston swaps should be kept to piston cars but I wont get into the 'ethics' of that here. What I will mention is that for the same time and effort a LS1 or other potential motor would more readily fit and offer better initial gains. Honestly I'd look at 3-rotor clips or a Cosmo 13B-RE and some nice port work.

exhaustnoteV2

iTrader: (9)

How about we mention that a stock KA24DE has about 140-155 flywheel hp. Not very exciting. I had a KA in my 240 and I've had a few SRs.

The amount of money, effort and time it'll take to get it to work isn't worth it in the end. You're spending money (and a lot of it) to lose power.

Nihilanthic

Who the **** is going to use a STOCK KA24?

Did you just miss the post from dopefish, and my own post linking to a website to several KA24s over 700 hp at the wheels before his??

http://www.ka-t.org/ <- Maybe you'll notice it now?

And in the future, READ THE THREAD BEFORE POSTING PLIX

Flipper

I personally would keep the rotary in the car it came from. With that being said I have owned a couple 240's and have lots of experience with many different motors and the KA has a LOT of potential.

iceblue

Oh nice in that case maybe we should start posting the 1000whp 13bs and they dont even require swaping.

now take your truck motor POS and blow yourself.

exhaustnoteV2

iTrader: (9)

You'll notice he never mentions a turbo in his original post. Also, the title of the thread is, "KA24DE in a rx7", not "KA24DET in a rx7".

Dopefish, I'd hope the KA makes more power than the SR. the KA is a 2.4L while the SR is a 2.0.

Nihilanthic, is it necesary to be so rude? You KA guys always have such a Napoleon complex...

fidelity101

iTrader: (11)

1000 crank hp and 9.7 in the 1/4 aint weak.

Nihilanthic

Stock 1000whp 13b? Where?

How much would you spend on getting a 13b to that much power? Or, more relevantly, how much would you invest to get a 13b to the same power as a KA24?

I can tell you now that you wont have the same MPG for a street car (and lets not kid ourselves, they ARE street cars) or as much torque, and if you dont know why thats your problem, not mine.

So yes, please do post with a cumulative cost to do it how much it would cost.

That said, its arguably a better idea to do it in a S13 if you can find one cheap, but the ricer-flation has driven up the price. Plus, all the SR20DET-bandwagon guys tend to give away KAs, and FCs with trashed engines are hardly rare, so you do the math.

But anyway, saying irrelevant, stupid **** like 'truck motor' just makes you look more like a stupid ricer fad-chasing dumbfuck than you actually are, especially when "REPU" and the SEARCH BUTTON could make you have to eat your own logic.

Nihilanthic

Im not a KA guy. Im a "LIMA" guy, and that motor happens to have a few things in common with the KA (similar displacement, SOHC like some KAs, a not well known turbo mill...), except it started life in the pinto, so I guess Im some random *** swapping a motor in Mazda's holy rotary chariot

I really dont like ricer idiots who come in, dont read the thread, and then spew their typical nonsense. The "truck motor" arguement is especially foolish. What is a 'truck motor'?

Its an epithet that speaks volumes of his perspective and what he actually knows vs what he THINKS he knows. So yeah, Im gonna be rude at someone who cant scroll down and read before opening his textual mouth.

adictd2b00st

the problem with the KA tho is it will never be a high reving motor. the stroke is too long. it will make a boatload of torque if turbo'd tho. depends what you want to do with the car i guess, personally i'd look to another motor, but that being said there are worse choices than a KA too

Nihilanthic

For one, thats incorrect. 96.0 millimeters = 3.77952756 inches <- thats NOT too much to rev with, with forged rods... but the real thing is you dont NEED to rev very high if you can make the power at "low" rpms. I can name a ton of v8s with 4" strokes that can rev as high as you want to build them to run, but the real honest to god truth is thats not exceptionally long and theres no good reason to focus on rpms as a measure of performance.

Its all about power to weight. Revs are a means, not an end, unless youre stuck with short tires, short gears, and youre making so much power you top out too early, and its more expensive to change gearing than to rev up... with turbo motors anyway. Now if you have a ginormious turbo then you need rpms to spool it, and a few more than that to actually have a useable powerband, but thats not such a necessity with 2.4 liters displacement and good headflow unless youre going to ridiculous lengths... yet, again, thats only for race conditions, and you can just get some real strong rods and go for all the revs you want.

Being around rotaries and short gearing might make you think revs are 'good' or a necessity, but therye just another means to the same end.

Ignoring VE, a good way to tell how much power a engine can make is to just multiply the displacement by the rpms it can rev out to. Just for a quick example, comparing a 302 (a 5 liter v8) that revs to 8K vs a 402 (about 6.6) liters that revs to 6K rpms, they both end up about the same in terms of how much power they can move assuming the same VE and are equally unrestricted. Both have the same bore, just one is a 4" stroke. The 402 will be easier to drive, have a much milder and better for mpg cam, have more torque and make the same power the 302 does at lower rpms, and granted you can properly gear it, it will generally outperform the 302 assuming the two motors are in cars of equal weight. The difference in stroke on the crank will have a negligeable effect on weight, btw.

Doing the same sort of math, 2.4*6500 = 15600. Now, 15600/2 = 7800rpms.

Now, which one woudl you rather play with, a 7800rpm 2 liter or a 6500 rpm 2.4? Sure, the SR20 would 'scream' and have the tach needle fly all over the place, but it wont be any faster than a KA24 of the same power, and torque will be to the KA's advantage.

exhaustnoteV2

iTrader: (9)

Let me translate the above statement for everyone, "blah blah blah, blah blah blah blah. Blah blah blah; blah! Blah, blah blah? Blah, blah blah!"

Nissan put the KA in the 240 to save costs and forgo having to get the SR20DET past emissions...Keep your KA and enjoy--it still sucks.

Nihilanthic

Right, knee jerk emotionally like a baby and ignore the facts.

Youre just pissed off that your assumptions dont match with the facts and cant face them, so you reject them, and then waste everyones bandwidth to go 'bla bla bla'.

Just tell me, how the **** is a smaller motor that cant pass emissions better than a bigger one that can and that can out perform it pound for pound?

Well, wait, this IS a rotary forum...

adictd2b00st

go on any nissan forum and ask them why the KA can't rev. BECAUSE THE STROKE IS TOO LONG. go on KA-T.org, the biggest supporters of the KA, and they'll also tell you the same thing. oh wait i forgot tho, you know everything.

Nihilanthic

Im fairly sure the stock cam's duration and timing, and the valvetrain, has a lot more to do with the revability than the stroke. Also, the fact that theyre making a **** of a lot of power below 7K rpms means THEY DONT NEED TO. Stop looking through rotary clolored glasses at everything, and maybe you might want to try to understand.

I laid it out rather clearly that the KA can do the same at 6500 rpms, what a SR needs 7800 to do. And any idiot (well, dunno about you) knows the longer the rev range is, the less of the total rev range can be volumetrically efficient. So a shorter rev range, more of it useful (higher VE), the same power, and more torque. Thats BETTER.

Stop getting so hung up on RPMS. Its fine. If you have a need to rev that high and want to spend the money on it, youre more than welcome to get some long, forged connecting rods and the right pistons and set it up to rev higher, and then get cams and valve springs that actually work at higher rpms, and take a chunk out of your low end for the sake of watching a stupid needle shoot farther to the right.

A KA is no different than any other motor, the right parts and enough money and it can do what you want. Unless, of course, the KA has a ridiculously short rod to stroke ratio, but I doubt thats the case.

EDIT: I just did a ******* google search.

For the KA24(D)E, that rod ratio is: 6.496 / 3.780 ~= 1.72
For the SR20DET, that rod ratio is: 5.366 / 3.386 ~= 1.58

Pucker up and kiss my ***, idiot. The limit to revving a KA is the cam profile, and thats easily changed. If youre worried about piston speed, get some good pistons and some good forged rods, balance the assembly, and then slap yourself for wasting money on revving a motor high that doesnt have to.