Turbocharged KA24DE vs SR20DET Swap

[Nathan]

they both end up being expensive.

Can I get an AMEN? I have gone through most of the options for swaps and turboing the KA and found that once you want over 300hp, things really start to equalize. In order for me to feel comfortable pushing a good bit of boost on a KA, I want it rebuilt for peace of mind. The SR, the aluminum block scares me and you have the initial purchase price in there, the CA is sturdy as can be but it takes more boost, better tuning etc. to get that kind of power out of it. The RB, you have a higher initial buy in and right now it's taking a while to get RB's. For me it came down to the peace of mind of an essentially new motor (rebuilt KAT), about the same price, power etc. but ease of finding parts for it. If I could have put up with the wait, I would have probably gone RB25 for the iron block, extra displacement, and sexyness of in inline 6.

[Nathan]

I have never heard of crankwalk in KA's, although the blocks are designed similarly, the oil squirters (one of the suspected causes of crankwalk) operate differently and imo, would be hard pressed to get stuck open like the ones in the dsm's supposedly do. Here, I was reading this: http://www.magnusmotorsports.c...y.htmAlso, I can tell you that the thrust surfaces of my KA bearings looked perfect after 110,000 miles. No copper showing, nothing, if I didn't know better I'd say the bearings that came out of my engine were used for about 1000 miles of break in and nothing more.

Edit: another possible cause of crankwalk is bad oil pumps, something that doesn't seem to be much of an issue with KA's either.

[Hellion240sx]

around hpw much you looking at for 12 sec.'s for the sr and the ka-t? if i could run 12 secs all day i would be fine. heh thats all, is that too much to ask for?

[Hellion240sx]

hp and $$ wise

[TS240sx]

240sx US Spec comes with KA engine with weight distrubution of 54/46, with SR in it, makes it 50/50 which is the best weight distribution, and i have seen SR boost to 400hp with stock internal, and 600~800 with rebuilt engine, but KA can only hold about 250 with stock internal........i dont know, what really convince me with the SR is the strong stock internal and the 50/50 weight distribution, b/c i only want to run about 280 at the wheel, thats all i am looking for, so if i get a SR, i would be spending less money than KA and not having to worry about rebuild the engine, again, this is my personal opinion.....

[jdmfreak]

hp and $$ wise

I also want to know.

[Onizuka]

I definatly agree with you about the price but where do you get your info about the sr block taking more power than a ka i may be wrong i'm semi new to the concepts but isn't a ka block iron and a sr is alminum i'm not sure but i know metals my dad owns a tool and die company and iron and steels are stronger under pressure and heat than aluminum throw a TIN can into a fire and a aluminum can in with it and watch which melts first

aluminum block with iron sleeves, good for cooling and strength, slightly less durrable than an iron block (not weak by ANY standards). The current record in the U.S. im an aware of is 539hp on the stock SR bottom end (and stock block of course).

KA has the obvious advantages of displacement and domestic availibility but has a comparitively weak bottom end and lack of factory turbo accomodation.

The argument of which is better or which costs more is stupid. I have never seen or heard of 2 completed turbo projects that costed same. Even if two people buy the same turbo kit with the same options and install it all by them selves one person will end up spending more than the other be it by having to replace some stock parts or having to rebuild the motor before they turbo it.

Do what YOU want to do, not what some weenie on the internet tells you is best.

If someone tells me that KAT is better i just shrug it off because i really dont give a damn, Im doing my own thing.

[Jookmasta]

i struggle with the same question day in day out. sr or deal with what i have. hmmmm. see the real question is personal preference. not to mention mileage. i have 120 on my KA and me turboin an engine with 120 is very scary. i know KAs can hold their ground on the longevity but with a turbo, the life span may be cut in half. is it a risk you are willin to take? personal preference.

[droptopsilvia]

damn, theres too many choices....and none of them are better or more cost efficient than the other **** me, dammit, what the ****, ****, ***,*****, ****,....excuse me while I go drive my car through a fence!!!!

[Nathan]

Droptop, just do what YOU want to do, you can't really go WRONG, they are all very nice motors. J-Spec has the right attitude, he's happy with what he's doing and isn't going to let anyone else's opinion change him. TS240, I dont have time to get into the physics of it, but a 50/50 weight distribution is NOT necessarily perfect and there is very little difference in the KA and SR weights anyway. Just because it's aluminum doesn't make it light, they used a LOT of aluminum in that block. Besides, I can tell you that a KA block is under 80 lbs. because it's easy for me to pick up. If I had a scale I'd weigh it...but it's not really important, the block isn't what makes the weight difference really.

[Charlie240sxt]

Ther are stock Ka's that have laied down 300+ stock bottem end and then rebulid and proven to hold over 600HP.The Sr does not give 50/50 its still off just not as much, but thats fine for the longer stroke and .4 disp. the Ka gives along with strong block and Tq

Not only that but ther both really good motors 4 bangers at can lay down over 700 to the wheels and that right ther is what we should be proud of not what one is better

[SHIEF]

Nothing wrong about it, I see it constantly. Funny even when I was looking to turbo my Ka, I was steered away by a major performance company in central Ohio.You can say wrong till your blue in the face, instead of disagreeing, say why you feel its wrong. Every car I have seen with a turbo kit had problems after a year or more and ones designed with one didnt.You can thrash a supra, mitsu, sr20, 300z...the list goes on for turbo model cars all with thousands of miles on them and still ticking, cant say that about a bolt on.

Just my opinion

I hope your not talking about PASSEN, they are a joke and always will be.

[droptopsilvia]

Droptop, just do what YOU want to do,

hahaha thanks but I was joking around!

[Hellion240sx]

ts you have a good point there, makes me lean more towards the sr swap. runnin how much boost, stock to reach 400hp?

[SHiFT]

IMHO, the sr/ca swap is the best bang for the buck. You pay about 1500-2500 for the swap(s) and start out with a turbo ready motor that can handle more boost than a stock ka with just a turbo kit. If I wanted boost, I would opt for the ca personally.

As with everything, this is just a matter of opinion and ignorance is involved here as well. The SR is nice yes and the JdM HyPe makes it seem awesome too but the facts show otherwise. If you're capable, you can turbo the KA like AceintheHole for $996 and run 5.3 0-60 times with a T3 volvo turbo. You at least know what you're working with, don't have to pull the engine out, know how you've driven it, don't have to make a new wiring harness, keep your ac, etc. About the SR holding more boost, thats a half truth. If tuned right the KA can run 15+PSI all day on stock internals. The only weakness is the piston rings. The rods and crank are forged and the engine is an iron block (capable of 800+ hp). The 2.4 liters and long stroke allow the KA-T to produce more HP and even more torque than the SR would produce at double that PSI. I'm not bashing the SR, its a good turbo engine, but the numbers speak for themselves. A well turboed KA goes from 137ish HP to about 220 HP at the wheels with adding 5-6 PSI. The SR makes about that much at 10-12+ PSI after replacing the intercooler/exhaust/downpipe/bov, etc ($$$). I'm relating all this to about the 230-250 HP range (good street car). With turbo KA you get to start out with a T3/T4 or the like, with the SR you buy all the stock stuff, then buy new stuff again to make it better. After the 250hp range or so, then you get into the heavy engine work, in which case both engines prove themselves nicely I think. I met Ken at Enjuku and his project S13 SR has 496HP with stock internals and runs 10s. Thats real impressive. You could do the same with the KA as well once you've replaced the internals. My point is however, for a good street car I think the KA would be the wisest choice, if you know what you're doing. To fix the high KA mileage concern, it would be wise to implement a rule like say - If the engine is under 120K, turbo the KA, if it's over 120K, swap an SR in. Thats what I would do but thats my opinion. Hope this helped.

-Erin

[Onizuka]

ok, im not saying your totally wrong, but im just going to point out a few things..

As with everything, this is just a matter of opinion and ignorance is involved here as well. The SR is nice yes and the JdM HyPe makes it seem awesome too but the facts show otherwise.

Its not the "jdm hype" that makes it "seem" awsome, its the motors amazing performance capabilities and product support that make it amazing, just like any other turbo nissan motor (including the KA-T).

Quote »The only weakness is the piston rings. The rods and crank are forged and the engine is an iron block (capable of 800+ hp). [/quote]so can the SR block :rolleyes i dislike when people alude to the SR block being weak, because its definatly not.

Quote »I'm relating all this to about the 230-250 HP range (good street car). With turbo KA you get to start out with a T3/T4 or the like, with the SR you buy all the stock stuff, then buy new stuff again to make it better. After the 250hp range or so, then you get into the heavy engine work, in which case both engines prove themselves nicely I think. I met Ken at Enjuku and his project S13 SR has 496HP with stock internals and runs 10s. Thats real impressive. You could do the same with the KA as well once you've replaced the internals. My point is however, for a good street car I think the KA would be the wisest choice, if you know what you're doing. To fix the high KA mileage concern, it would be wise to implement a rule like say - If the engine is under 120K, turbo the KA, if it's over 120K, swap an SR in. Thats what I would do but thats my opinion. Hope this helped.

-Erin [/quote]

:thinker

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[Hellion240sx]

yeah sr im close to 150k and TICKING LOUD AND CLEAResp. when they change the oil its horrible

[Onizuka]

i dont think there is anything wrong with turboing a high milage KA, its just a rebuild would be suggested first.

[Nathan]

I tore down a perfect KA with only 110,000 miles on it to rebuild it for turbo. I dont like the stock pistons AT ALL, neither do I care for the rods after seeing one bent in half. I decided that to really lean on just about any engine, I would want to rebuild it if nothing else for the "new motor" aspect of things and to make sure everything inside is healthy. One thing I was not aware of though was that the SR has iron cylinder liners, I thought they were just aluminum but nikasil lined?

[SloMoe]

Nothing wrong about it, I see it constantly. Funny even when I was looking to turbo my Ka, I was steered away by a major performance company in central Ohio.You can say wrong till your blue in the face, instead of disagreeing, say why you feel its wrong. Every car I have seen with a turbo kit had problems after a year or more and ones designed with one didnt.You can thrash a supra, mitsu, sr20, 300z...the list goes on for turbo model cars all with thousands of miles on them and still ticking, cant say that about a bolt on.

Just my opinion

Look If its built right it will last. Even on stock internals

[Onizuka]

that S14 is mad sexy!

[Jookmasta]

so would everyone here say rebuild my 120,000 mileage KA or do the SR way? i only want 250 or so at the wheels. i just want 12s at the track.lol. but i also only wanna spend 2500. any thoughts/comments

[Nathan]

man, with only 2500...I dont think you can pull it out of an SR for that price. I think you really ONLY have the option of turboing the KA with a budget setup and hoping for the best. Just my opinion.

[Turb0wned]

i would go ka-t thats what i wanna do its easer to get dont have to do the swap it could be cheaper

[Nebraska240sx]

IMO i would go KAT, just to be unique in my own way, or even superchargine the ka. not MATTER WHAT ITS A GOOD IDEA TO REBUILD A BLOCK BEFORE PUTTING ANY MAJOR POWER IN IT, KINDA LIKE CLUTCHES, YOU NEED TO BEEF UP EVERY THING TO HANDLE SEVER POWER. bolt ons will do ok on stock internals, and even low boost, but if u want to be able to drive your car cross country/road trips/long trips id rather have the ka just to get parts easy, hell even if i was just driving to work every day, id rather be able to get parts affordable and quickly, not having to be with out a car for a few days, while i wait for a water pump to be air mailed from japan (long story). I just think it seems easier to have the KAT, and learn to build it as u go not just buy something and drop it in.

[w1ngzer0]

yet another vs this vs that post. hey look it got flamed oye :rolleyes

[NS180]

while both motors are great in there own way for the money you get more with an sr such as a transmission stronger ignition stronger block lighter and its built for a turbo. I belive that in the long run you will spend much more money on a kat to get in the 350 to 400 hp range, a great thing about the ka t is that if you blow it up there are plenty around to pick one up cheap.

[SHiFT]

how is the KA transmission weaker than the SR transmission? Nissan put great trannys into the KA powered cars. Have you heard of anything wrong with KA trannys?

[w1ngzer0]

ok stop this is better then this and thats better then that this post is crap. btw NS180 what engine do you own?

mods should start deleting topics like this cause its getting old.

[Charlie240sxt]

Ther both good motors. Both have proved that with laying down over 300 to the wheels on ther stock bottom end. The Sr does not have the Tq the Ka has. But the Ka doesnt have the top end the Sr has and i would bet its cheaper to go Ka to 300hp then Sr to 300hp cuz you allready have the Ka and only abput 400 to get anther one