SR20DET vs Turbo KA24

[cartoonman]

By no means am i an expert...i just hope maybe this will help some people wondering...feel free to add or correct any mistakes...i just want to offer my personal opinion

Now to start off...i'm sure your all familar with the KA24 and SR20 engines

SR20DET205hp @ 6000rpm203tq @ 4000rpm

KA24E (89-90)140hp @ 5600rpm152tq @ 4400rpm

KA24DE (91+)155 @ 5600rpm160 @ 4400rpm

of course the SR20 has the advantage stock...but take away the turbo at the SR20 puts out 140hp and 133 tq...(the n/a sr20 is a higher compression)

So at first look comparing all the N/A versions of the engines...the KA24DE has the advantage in hp and torurqe

(you'll catch on quick that i'm trying to promote using the KA series engines over the SR20)

Now from browing around a bit over time it seems the general consensus is to a SR20DET swap and a Turbo KA24 setup will cost you about the same in the end

Here's where i get into each engine

Now the SR20DET has the advantage of coming with a turbo and having very strong internals on it...allowing it to be pushed to higher boost levels on the stock engine (new injectors, cams, etc. are needed) very easily. Being a DOHC setup it revs very high and has great top end. Although the smaller displacement has a lack of torque

The KA24E, a nice old truck engine, with it's SOHC 12 valve design produces more low end torque then hp. That is actually an advantage in most cases. But due to the 12 valve design it lacks the efficiency of a DOHC 16 valve engine, making it require higher levels of boost for the same power output. The main problem that plauges KA24's is it's lack of strength since the engine was never made to be turbocharged

The KA24DE, a DOHC 16v version of the old truck engine, still used in nissan trucks of the same year, has increased efficiency due to dual cams and 16 valve. This adds 15 hp over the KA24E but only 8tq. Even though the torque increase in minimal it the ratio of torque to hp is still greater then the SR20, thanks to its larger displacement

Now as for turboing them. The SR20 comes with a turbo so we won't worry about it yet

The first thing if you do decide to turbo a KA series is head over to http://www.realnissan.com and pick up some of there parts to strengthen up the low end of the KA24

Now as for a turbo kit, I believe in building your own, RealNissan does offer them, but you will find it much cheaper and more of a learning experience in the end

I'm going to use some various calulations the produce some estimates on each of these engines

Say your goal is 300hp on one of these 3 engines, sounds reasonable for a real enthusiast. For these first estimates i'm going the stock engine efficiency (for those who don't know...the efficiency is the percent much air that comes through the intake compared to how much com,es out the exhaust, turbos are power by your exhaust so top end work is the best way to increase power on a turbo engine)

First off...

SR20DET

The stock efficiency is approx 93%With that efficiency, an average size turbo, and an intercooler it would take approx 18psi of boost to produce 300hp and 282tq

(As you can 18psi is hard to run without detination thats why increasing the engines efficiency is essential IE: with 100% efficiency it would only take approx 16 psi to create 300hp. It is entirely possible to get upwards of 100% efficiency on DOHC engines IE: with lot's of head work 115% is a possibilty)

Next

KA24E

Stock efficiency approx 83%With that efficiency it would also take approx 18psi with the same turbo setup to produce approx 300hp and 322tq

(another thing to remember is a larger turbo moves more air...therefore the larger turbo will increase the power more at lower psi levels...my estimates are for a turbo perfectly suited for this displacement engine, that would be a turbo that has compromised levels of exhaust backpressure and turbo lag)

Last

KA24DE

Stock efficiency aprrox 92%It would take only 15psi to gain the same 300hp as the others...with that 15 psi the KA24DE also reaches 311tq

(imagine a KA24DE at 15psi and 110% efficiency *evil grin*)

I'm sure your getting tired of reading this so i'll get to my point

SR20DET - 300hp 282tq 18psi KA24E -300hp 322tq 18psiKA24DE - 300hp 311tq 15psi

see those numbers..not just hp but torque and psi levels

that's were the benefits of turbocharging a KA24 comes in, no replacement for displacment as they say

if you took 3 240SX's with all three engines lined them up each producing 300hp and had them drag race...who do you think would win?

point being...hp isn't everything...if you don't have torque horsepower is pointless...that being said the 18psi KA24E would be approx 2 tenths or more faster in a quarter mile...while not much...take a KA24DE and add the same boost level as the SR20...and hp and torque will be much higher compared to the SR20

Remeber these numbers are estimates...that no engine can handle 18psi without some work...also i am no expert as i said...i myself have a lot to learn about turbos

But my point is unless you want a J-Spec 240SX...keep your KA24 engine...or if you have a KA24E find a cheap KA24DE somewhere...they have much more potential then they get credit for

I'll make one final estimate for you

Take a KA24DE and focus on the top end...make it flow the best possible...with that kind of efficiency in your top end you can pull approx 340hp out of 12psi of boost...bo SR20 can do that at the same efficiency

BTW I no longer own a 240SX, it was torn apart by two kids before me, so it didn't have much life left..I now drive a Turbocharged Pontiac Grand Prix

[hannibal]

Wow...I'm curious as to how you came up with those numbers. Where did you get those efficiencies from?? And how did you come up with those boost levels required to make 300hp??

BTW there are quite a few guys running stock internal KAs making well over 300whp at 15?psi...

[cartoonman]

Wow...I'm curious as to how you came up with those numbers. Where did you get those efficiencies from?? And how did you come up with those boost levels required to make 300hp??

BTW there are quite a few guys running stock internal KAs making well over 300whp at 15?psi...

Just some equations i've found while studying turbo stuff...honestly i can't guarantee there accuracy..but i've tested them out on some cars and they come pretty close...others they're off a little bit

Just out of curiosity...the 300+hp KA24's you're refering to...are they stock heads, cams, and valves...because like i said..even a just porting a head can cause a substanstansial increase in power on a turbo engine...if the top end is stock then well...my numbers are off...or they're running a larger turbo

[hannibal]

Dennis at Unstable Hybridshttp://uhrp.com/Projects.html

AFAIK Completely stock motor from the head to the block.

If youre talking power at the crank, your calculations may be fairly accurate.

Wanna share where you got these formulas and what assumptions (which turbo) you made?

[cartoonman]

347.3 RWHP...GEEZUS!

anyways...um i guess my stuff is off a bit...i've got the stuff from various sources...i used a nice java based calculator on some guys site...it's proved accurate when it came to GM motors in relationship to a T25 turbo on a 3.1L V6...the turbo calc is here http://3kgt.bowtiecrawler.com/turbocalc.html..maybe the turbo efficiency is greater on the KA24 turbo set up on that site...i mean theres so many factors

I'm been studying turbo charging so i can work on maximizing the turbo set up on my grand prix..like i said i need to learn a lot more

Plus i hate hearing people diss the KA24...and that site you posted helps back up the fact KA24's have a lot of potential

If you can do that on stock internals i would agure that KA24 is the cheaper and better route to go...i never understood swapping in a smaller engine that costs more and produces less torque

[Nismo_Freak]

You are leaving out a ton of other factors... it's also been argued and argued and argued time after time and there is no clear victor.

I chose an SR... I have my reasons as would anyone else for that matter choosing an engine. Both engines are capable of producing power, neither can be built for any more than the next. KA's will almost always have the torque advantage but it's nothing to gloat over. Equal hp and more torque just means the KA makes it's power down in the midrange and the SR breathes better on the top end, which just so happens to be the case.

BTW, first person to cuss or get out of line and thread gets locked down.

[cartoonman]

i agree i don't want thsi getting out of hand...

If you make a KA24 bretahe just as much as an SR20...the KA24 is going to put out more power due to it's larger displacement...am i not right?

I mean stock for stock...yes the SR breathes better at high rpms...and the KA24 has better low end power

But with some work on the top end...you could make a KA24 breathe as good as an SR20

I mean i see one benefit of the SR20 being it's plethera of performance parts...but the KA24 will alway be more capable if the right work is done cause of the extra 400cc's it's packing

If you have 2 engines...same # of valves...same number of cams...same level as volumetric efficiency...but one is 2 Liters and the other 2.4....the 2.4 will always have more power output...but only if the volumetric efficiency is identical

Edit: I think i see why you choose SR20 now...i'm going more for a no replacement for displacement standpoint...but the SR20 would have it's benefits...to each their own

[Nismo_Freak]

i agree i don't want thsi getting out of hand...

If you make a KA24 bretahe just as much as an SR20...the KA24 is going to put out more power due to it's larger displacement...am i not right?

I mean stock for stock...yes the SR breathes better at high rpms...and the KA24 has better low end power

But with some work on the top end...you could make a KA24 breathe as good as an SR20

I mean i see one benefit of the SR20 being it's plethera of performance parts...but the KA24 will alway be more capable if the right work is done cause of the extra 400cc's it's packing

If you have 2 engines...same # of valves...same number of cams...same level as volumetric efficiency...but one is 2 Liters and the other 2.4....the 2.4 will always have more power output...but only if the volumetric efficiency is identical

Edit: I think i see why you choose SR20 now...i'm going more for a no replacement for displacement standpoint...but the SR20 would have it's benefits...to each their own

I chose the SR because my KA was FUBAR. I faced having to give up one of the better points of the KA-T (you don't have to buy another engine) and risk even more downtime as a result. So logic told me to just go for the SR. I'm happy with my decision, even though I've only driven the car twice for about 5 minutes each.

I could have built a budget KA-T that would make more power for what I spent on the SR... but I don't care. I do what I want to do regardless of what I "could have" or "should have" done.

If you have a 2.4L engine and a 2.0L engine ceteris paribus the 2.0L engine will make more power. This is due to the mechanical and spacial efficiency the 2.0L engine will have over the 2.4L.

However you later moved the arguement towards efficiency. If the two are equally efficient in every aspect the 2.4L will make more power because it is able to injest more air which allows more fuel to be burnt, etc.

However add one benefit the SR has over the KA, rpm. The SR can turn at 7200 rpm stock. The KA (in my year) turns to 6200 rpm stock.

7200 x 2 = 72006200 x 2.4 = 7440

While the KA displaces 25% more volume in one revolution the effect is minimalized to a mear 3.3% at redline. This is mearly numbers... actual numbers will vary, but it's only to bring another aspect to the arguement.

[Megaseth]

i dunno about making the KA breathe better. the SR has a much better head design than the KA. i know even with cams, and a port and polish, the flow wont be anything to brag about. im sure with a large redesigned intake plenum along with port and polish, cams, and bigger valves, the head will flow well, but not as well as an SRs.

If i had the chance, i'd probably go with an SR just because its an engine with a stock turbo. it was designed with a turbo in mind and there is a larger aftermarket for it. i like the uniqueness of the KA-T, but the SR just has the back up and ease of finding parts.

BTW, any pics and stats on your Grand Prix?

[knowleqe]

cartoonman, what was the whole point in your rant? seriously. this ka vs sr thread keeps going on and on. stop bringing this up, use the search button please.

[PhaneSoul]

ok, he wasnt asking a question, nor was he trying to start an argument or trying to see which was better. He was stating information that he came up with and researched. I was very amazed with his numbers and i think even some of the other 1000 post guys were glad to see info like that. IF people want to post info let them, this IS a forum. What a forum if you cant post what you want? I understand the question goto search button thing, but in no way was he asking a question. The whole point in his "rant" was he was stating information. If you dont like poeple posting about ka vrs sr, ka vrs ca, ca vrs sr, then please stay out of the threads. In no way am i trying to insult you or anyone on this thread, and im definitaly not tryin to get it locked (im refrainind from using cusswords) if you dont like the subject, dont read the thread. I know now instead of just using my stock kae engine and fixxing it up, this has helped me make my final decision in buying a kade and fixxing it up and seeing how close to cartoonman's numbers i can get.

Thank you cartoonman

And remember boys and girls, if you dont like the game, dont play it, you get in the way of the people that enjoy these little talks.

[downshift]

And remember boys and girls, if you dont like the game, dont play it, you get in the way of the people that enjoy these little talks.

I agree. This was an entertaining discussion. It shows that most of us here on NICO can act like adults and have an actual discussion minus all the negative people who just hop in and try to flame. I always had my mind set on the KA24DE anyway...now maybe i might just be able to influence my brother.....he is the SR type. Thanks cartoonman.

[Nismo_Freak]

ok, he wasnt asking a question, nor was he trying to start an argument or trying to see which was better. He was stating information that he came up with and researched. I was very amazed with his numbers and i think even some of the other 1000 post guys were glad to see info like that.

His post, although very misleading and severly lacking substantuated evidence supporting the claim, is indeed alot more than some members put forth regarding the issue. It's for that reason this thread is still here.

IF people want to post info let them, this IS a forum. What a forum if you cant post what you want?

Not a hack at you, but this is indeed a forum, however it is a private forum by form. Therefor we as moderators/admin reserve the right to modify/delete/remove selected elements from NICO at any time for any reason.

However as it's well known, we typically have good reasoning behind our actions.

[PhaneSoul]

Not a hack at you, but this is indeed a forum, however it is a private forum by form. Therefor we as moderators/admin reserve the right to modify/delete/remove selected elements from NICO at any time for any reason.

However as it's well known, we typically have good reasoning behind our actions.

And were u hacking at me or knowledge? Damn it ima cry if it was me!! j/p

[knowleqe]

i do understand the fact that he posted up some valuable information. it seemed to me that the first half was pretty much how most people start off with in the ka vs sr threads. phanesoul : i read each and every post in the general and tech forums

[C-Kwik]

Quote »Now the SR20DET has the advantage of coming with a turbo and having very strong internals on it...allowing it to be pushed to higher boost levels on the stock engine (new injectors, cams, etc. are needed) very easily. Being a DOHC setup it revs very high and has great top end. Although the smaller displacement has a lack of torque[/quote]

The internals are not significantly stronger. Teh pistons are of lower compression but other than than that there are no really significant advantages. They are made using the same casting procedures as the KA parts. The rods are beefire, but I'd speculate it is to deal with the higher RPM's the SR operates within.

Quote »The KA24E, a nice old truck engine, with it's SOHC 12 valve design produces more low end torque then hp. That is actually an advantage in most cases. But due to the 12 valve design it lacks the efficiency of a DOHC 16 valve engine, making it require higher levels of boost for the same power output. The main problem that plauges KA24's is it's lack of strength since the engine was never made to be turbocharged[/quote]

I don't giving up power for torque to be an advantage. I'll explain more about HP and torque later.

Quote »Say your goal is 300hp on one of these 3 engines, sounds reasonable for a real enthusiast. For these first estimates i'm going the stock engine efficiency (for those who don't know...the efficiency is the percent much air that comes through the intake compared to how much com,es out the exhaust, turbos are power by your exhaust so top end work is the best way to increase power on a turbo engine)[/quote]

Actually the Volumetric efficiency has to do with the overall breathing relative to the displacement. In otherwords, how well the motor moves it's displacement of air. A 2.4L motor with 100% VE would move 2.4 L of air every 2 revolutions.

First off...Quote »SR20DET

The stock efficiency is approx 93%With that efficiency, an average size turbo, and an intercooler it would take approx 18psi of boost to produce 300hp and 282tq

(As you can 18psi is hard to run without detination thats why increasing the engines efficiency is essential IE: with 100% efficiency it would only take approx 16 psi to create 300hp. It is entirely possible to get upwards of 100% efficiency on DOHC engines IE: with lot's of head work 115% is a possibilty)[/quote]

To produce over 100% VE on an NA motor, it requires high overlap cams with a matched header to pull air thorught eh combustion chamber. 115% seems a bit far fetched, but I've never heard the rated VE of any NA race motors. Keep iun mind VE changes with RPM as well. And turbo motors can't see a 100% VE. With cams that have high overlap, you'ld get too much reversion.

Quote »KA24E

Stock efficiency approx 83%With that efficiency it would also take approx 18psi with the same turbo setup to produce approx 300hp and 322tq

(another thing to remember is a larger turbo moves more air...therefore the larger turbo will increase the power more at lower psi levels...my estimates are for a turbo perfectly suited for this displacement engine, that would be a turbo that has compromised levels of exhaust backpressure and turbo lag)[/quote]

A larger compressor does move more air per RPM of the turbo shaft. But that is not always optimal. Compressor efficiency is just as important if not more important. A Large turbo may not run as efficiently at lower boost levels and flow rates as a smaller turbo. And vice versa. To properly size a turbo, you have to know what kind of boost you will run, what kind of flow rates the engine sees at that boost and the RPM's the motor operates in, the type of response and where you want the peak power gains to be.

Quote »point being...hp isn't everything...if you don't have torque horsepower is pointless...that being said the 18psi KA24E would be approx 2 tenths or more faster in a quarter mile...while not much...take a KA24DE and add the same boost level as the SR20...and hp and torque will be much higher compared to the SR20[/quote]

Okay, now an explanationi about HP and torque. They are in a sense the same thing. To increase HP at a particular RPM, you must increase torque at THAT RPM. Looking at the peak numbers only tells you part of the story. Torque and HP are a derivative of each other. If you know one figure and the RPM it makes it at, you can calculate the other. HP = (Tq x RPM)/5252.

HP is also more representative of what kind of results you wil see at the track as well. Torque is the amount of twisting force the motor puts out. HP accounts for the actual work done. 250 lb-ft of torque at 2500 RPM is different than 250 lb-ft of torque at 5000 RPM. Why? Because it is doing it at a higher speed. Why is this important? Because it can make better use of the gearing a transmission and final gear provide. Transmissions act as a lever for the motor. It allows the motor to put down a lot more torque at the wheels. When this is done, it also limits the speed in that gear. Lower gears multiply torque more.

So how does this relate to the RPM where torque is made? Using the 250 lb-ft torque as I stated above, through the same gearing, the points at which each make 250 lb-ft of torque will produce the exact same acceleration. But when driving hard, you tend to stay in the upper part of the rev band. A motor producing peak torque at 2500 RPM will probably never see peak torque being put out as the gearing will not allow the revs to drop that low. Where as a motor putting out peak torque at say 5000 RPM will likely see peak torque in each gear. That being said, it's important to try and maximize the torque you have within the powerband moreso than increasing torque at lower RPM's in a race motor. Consequently, a motor that revs higher has the advantage of being able to stay in a lower gear longer and use torque multiplication to it's advantage. This is why Honda VTEC motors can make power without a lot of relative torque. F1 motors also use RPM to increase power. These high revving motors do not make a lot of torque considering their power levels, but they make better use of gearing either by being able to stay in a lower gear longer or being able to use a lower gear ratio while acheiving similar shift points relative to vehicle speed.

This is not to say torque has no relevance. As I stated first, in order to increase HP, you must increase torque at a give RPM. But torque doesn't give you as broad a picture as HP does as a number.

Quote »Remeber these numbers are estimates...that no engine can handle 18psi without some work...also i am no expert as i said...i myself have a lot to learn about turbos[/quote]

Then you have a lot more to learn. Being able to handle boost has a lot more to do with than just the strength of the bottom end of a motor. This can very from motor to motor. Everything from Turbo size, intercooler efficiency and flow, to fuel octane, compression ratios can affect this.

Quote »Take a KA24DE and focus on the top end...make it flow the best possible...with that kind of efficiency in your top end you can pull approx 340hp out of 12psi of boost...bo SR20 can do that at the same efficiency[/quote]

The same can be done to an SR. What the SR lacks in displacement it can make up for with RPM. The KA has poor harmonics in higher RPM's(7500+) and can destroy itself there. It can be built to rev high and has been done, but these are higher budget race motors with little attention to lasting more than a season of racing...if that.

This argument has been made over and over again. Both motors are very capable. The SR has a clear advantage though in the fact that a lot of research has been done on parts and these parts are much more readily available. Of course this is going to really be advantageous at very high power levels, but we are talking about potential here, are we not? Mechanically each has advantages and drawbacks. A good tuner wil use the stregths of the motor they work with to their advantage while minimzing or eliminating the weaknesses. This being done, there is little anyone can say against each motor. I have no reason to believe neither motors can not produce insane levels of power. The SR has been done so for those who are looking to make the power without hassle can go this route. The KA is still unexplored in that territory, but we've only scratched the surface. Mike Lee in FA has surpassed 500 HP and is looking to make more with some minor imporvements. And that was on his "Shakedown run". I don't see the 600 HP level being very far off for him.

[cartoonman]

lol...wow...wasn't expecting this kind of turn out

overall i understand the advantage of a SR20 engine

I was going hardcore i guess...i mean if you have the time/money to make a KA series flow as good as a SR20 then i believe it would have an advantage

But that being said it would take more work then most people would like to put forth making the SR20 a much easier choice

I myself like to stick with the stock engine in most cases...just my bag i suppose...so now that i've heard some other viewpoints i'd say the SR20 is the quickest way to go...the KA24 setup i was referring to would require gobs of downtime and lot's of tuning...why do that when you can just swap in an SR20

I also agree KA24's are no where near as reliable as the SR20s...just take my KA24E in my old 240 for example...died from a bad headgasket, oilpan gasket, burned oil and leaked gas...ended up throwing a bearing at 181k...heck my current pontiac has less problems then my nissan

Honestly...I was hoping to offer a viewpoint and see if anyone would agree...and if they disagree i just wanted to know why...because i wasn't sure if my argument was really that good

I myself would take the time to turbo a KA24DE...i don't mind the downtime since i has 2 vehicles...Overall with enough work i believe it would yield some great results...plus i like to steer away from the norm...i won't be offened if this thread is locked now

And for the person that asked...I currently own a base model 90 Grand Prix...which will be gone soon...

The Turbo Grand Prix i was referring to is currently in my friends driveway...i still owe some money on it but it will be mine soon

It's a rare Factory Turbocharged 1990 Grand Prix...has a 3.1L Pushrod V6 with a t25 turbo at 7psi....transmission is a 4speed OD automatic...stock specs a 205hp 225tq...the engine is torque limited so with a new computer setup will produce more like 260tq...the engine is also capable of 300+ hp on stock internals and turbo setup...but my plans go far beyond that..it runs anywhere from 15.3 - 14.9 1/4 mile stock...weighs approx 3300lbs i have some pics here...it's incredibly dirty though http://rudefyet.co.nr/tgp%20pics/

[240Knightrider]

I was doing good until a KA24 was said to be unreliable. Very Untrue. Im running 220K miles on my stock parts. Not one part has been replaced except for the norm replacements (spark plugs, filter etc.) My timing chain started making noise a month and a half ago, My rings on my pistons are worn enough to make my oil burn out with in two weeks depending on how much I drive it. To school and work everyday. My Cat is cloged and fixing that problem monday. I cant believe the KA24 is any less reliable than any engine on the market whether that be the SR20 or A Vortec V6 to a 4G63T.

[hannibal]

Nice grand prix!I believe the Sr and KA are both great motors to work with. But the KA is better for a beginner. Theres a lot less money invested. You can pick up a new KA for less than $500.Until I feel more confident in tuning a turbo motor, I'm sticking with the engine that comes in the car.

[knowleqe]

i agree with c-kwik, btw where in socal are you?

[C-Kwik]

I also agree KA24's are no where near as reliable as the SR20s...just take my KA24E in my old 240 for example...died from a bad headgasket, oilpan gasket, burned oil and leaked gas...ended up throwing a bearing at 181k...heck my current pontiac has less problems then my nissan[/url]

I never said anything about the reliability. I can name a few 15 psi KA's that are on stock internals and have been boosting for some time now. The only thing I mentioned about reliability was how Race built KA's are not built with the intent to last more than a season of racing. The limitations of the KA's ability to rev comes from the poor harmonics at high RPM's. Reaching beyond these limits requires some reengineering. You can still make plenty of power without increasing redline. This should do little to deteriorate reliability if some good forethought and tuning is used when modifying the motor.

[C-Kwik]

i agree with c-kwik, btw where in socal are you?

Stanton. It's near Garden Grove.

[cartoonman]

ok...i musta misread somethign about reliabilty...sorry C-kwik

i mean yeah it's a reliable engine from what i hear...but my 240 proved otherwise...not saying it's a bad engine by all means! but a few lemon ones do slip through

my KA24E was a nightmare of an engine...that's a fact for me

i won't let that keep me from buying another 240sx though if the chance came up

[Mr1der]

McClaren Grand Prix?

those things are pretty hard to find...

[cartoonman]

McClaren Grand Prix?

those things are pretty hard to find...

Yes..yes they are...i'm amazed i found one in such a small city as the one I live in...overall there were a little over 3000 made in 89 and the same number in 90...quite a find IMO...defininitely one of a kind...and quite a buy at $2000 w/ only 87,000 miles

It's in serious need of a wash like i said...it's been sitting in someones yard for almost a year...the paint looks dull but it's almost flawless underneath the dirt...of course the front valance is beat up and the clear coat wore off the rear bumper

I need to grab a pic of the Heads Up Display and Driver Information Center...i think you'll get a kick out of some of the technology gm used in there late 80's early 90's cars

[Nismo_Freak]

The internals are not significantly stronger. Teh pistons are of lower compression but other than than that there are no really significant advantages. They are made using the same casting procedures as the KA parts. The rods are beefire, but I'd speculate it is to deal with the higher RPM's the SR operates within.

Incorrect, the KA and SR have different metallurgy, properties, and overall design differences that make a large difference in terms of a durability threashold. SR pistons are indeed stronger than the KA's ... it's aparent in the amount of power they hold. The 1 point of extra compression ratio does not account for 200rwhp of difference. The rods are indeed beefier, and shorter by a full inch which helps reduce piston speeds considerably.

And turbo motors can't see a 100% VE. With cams that have high overlap, you'ld get too much reversion.

Turbo motors match and exceed 100% VE... if not then there would be no reason for turbocharging an engine. An SR20 producing 300rwhp on stock components will at one point in it's powerband achieve 100% VE shortly before it exceeds 100%. An SR22 producing 700rwhp is EASILY above 100% VE.

Also, you can't rule out the presence of intake pulse tuning. It's what gives rotary engines in n/a form their power (bridge porting, etc.)

The KA is still unexplored in that territory, but we've only scratched the surface. Mike Lee in FA has surpassed 500 HP and is looking to make more with some minor imporvements. And that was on his "Shakedown run". I don't see the 600 HP level being very far off for him.

Veilside's Supra in 94' made a little over 500rwhp on stock internals using two TD05-18G's ... I've personally seen Supra's produce 1004rwhp on stock bottom ends using Y2K's and other large turbochargers. My point is... every year they will make more power and more power and more power the year after. To quantify a limit to any engine is for someone to deny progress. One day KA's will reach into the 700rwhp region... it's only time and effort away. I don't think we will see very much more out of the SR20, since the removal of the engine from Nissan's line-up it has lost alot of the large backing to produce enourmous amounts of power from the Japanese, but the US has started to take it on.

[ahbongkeo]

nismo_freak and C-kwik.......i am enjoying this reading. Learning mad stuff from it. Keep it coming ...........

[ahbongkeo]

i tried to make a poll just to see what most of the people in this forum prefer.....the ka-t or the sr swap including cost and power, but they took that off...can we have another poll just to see which 1 will win because i haven't seen a thread where there is a poll between the two

[Nismo_Freak]

i tried to make a poll just to see what most of the people in this forum prefer.....the ka-t or the sr swap including cost and power, but they took that off...can we have another poll just to see which 1 will win because i haven't seen a thread where there is a poll between the two

I removed it ... because I've been here long enough to know how those things always turn out.

[shinrekka]

KA24E will make the same power at the same boost level as the KA24DE do to higher compression

KA24E, custom turbo manifold, t3 turbo, custom piping, stock supra intercooler, 300ZXTT feul pump, 300ZXTT maf tube, 370CC injectors, 1g DSM BOV, Pep Boys intake Filter, Manual Boost controller, used oil lines,

THIS is a very cheap set up, made soaly of custom and junkyard parts. Good power can be had from this set up, although i have yet to do it because of not being able to find a damn manifold after realnissan.com just shut down (damnt again) and lack of a place to make my custom pipes

This setup, should however net 271 to the rear wheel at 9psi, safely, with an LSD and semi slicks, you should get a 12sec quarter varying were you live (elevation and ****). How do i know? Because i've seen this set up used and dynoed. Recently this set up was being sold on ebay and he said the same results.