Unique Swap (Disapointment KA vs SR) My story / theory
 

So I started out in the States, Washington State to be specific, about 3 years ago and I got me a 1990 240sx coupe. I was a young ricer then looking to go fast an do it sideways and flashy. I started to realize the stock KA24DE was not good enough for me, oh yeah the car came with the motor swaped already. I started looking into SR20DET's because they did not have jack **** for the KA at the time.

I started saving what little money I had up to buy an SR20DET, but was still looking at things for the KA that I might be able to upgrade or do in the process. (I always had the theory of why replace a motor when you can build what you have?) When I finally had enough money saved I noticed thing getting more and more popular with the KA and was reallizing I may no need to buy a whole new motor, so I decided to build a KA25DE(T) While I was on cruise I started bying engine internals and picked up a KA24DE Motor Tranny and ECU for $200. when I got off cruise i was going to star the rebuild and notice the 2.6 liter stroker kit and debated for a day and bought it 3 days after the kit was announced.

I tore appart the 91 ka and built the entire botom end of the KA, bored and stroked it to a 2.7 Liter and had the head resurfaced. stock top end and got rid of efery vaccume line ecept for the Fuel pressur regulator and redid the entire fuel system with top feed 550cc injectors, and got an AFC II for fuel control on the stock ECU. It was like a dream the car started first try and sounded mean as hell. I did the brak in period and went balls out from there on out. 5500 rpm red line sucked but I still got the car to 140-145 MPH no problem and could kick her sideways with minimal efort ie 2000-2200rpm throttle feather.

I then moved to japan and decided to take the 2.7 with me to build the head and turbo charge it. I wanted to by another S13 to be able to transfer parts back to my other car in the states. I got a 1989 with an SR20DET swap already done to it.

I was so excited to be getting an SR finally and to boot it is Turbo as well. I finally got in the car and drove it and was so dissapointed in the motor, but once again I have a theory of why replace a motor if you can build the one you have. well I feel that that theory is gone now considering the SR is such a finicky motor and it is only a 2 liter. I am trying to now find some parts to do a reverse SR swap. KA27DE(T) into the RHD Nissan Silvia S13! I am now anxiouse to get it done to be one of the first to put a KA in a real JDM s13 RHD and all. The purpose of this post was to see what all of you think of my Idea and maybe be able to get some contacts for some parts I need to do this Unique Swap.

well first let me start out by saying. i know where steve is coming from. this thread will not turn into a SR vs KA deal lol we have enough of those. if you have your reasons as to why one is better, state it and then provide factual first hand info.


LOT's of people swap SR's and they dont race them. When you race anything, you will began to see the pro's and con's of the motor. When i was home, there was only about 3-4 guys out of the 30ish or so i knew with SR20's that actually raced. 2 of them blew the motors with proper care.

they are not high performance engines. they just happen to be 7psi boosted motors from the factory. now when you get into the valve systems for the later SR's they get much better but the craze over the dated red tops in the states will never go away sadly...

I agree with Donnie, This is not a KA vs SR argument forum, More Just what people think of a KA in a RHD s13. I would like your inputs and advice on doing the swap because I have only helped with a couple of SR swaps in a LHD 240 in the states. We all have our reasons for going KA or SR, I was just more or less puting a background to my new Idea for a swap. Thanks again Donnie, I did not try to make this a SR vs KA forum.

no problem bro... as for the swap... its just reverse man...

great idea man, i look forward to seeing your build as it comes along

p.s. where did you find the 2.6 liter stroker kit for the KA?

Thanks. I ordered it from Brian Crower directly. I will post a build page when I start working on it again.

where exactly in wa are you from?

btw i love the 2.7ka idea, i thought about going up to 2.6l a few years ago but at the time it was more money than i had.

I am from all over. Mostely Utah, but I spent 4 years in Washington, Whidbey Island, near Bremerton, and the last year has been in Misawa, Japan.
I am very anxious to do the swap myself, but I want to do it right and take my time on it.

pfft, SR . . . KA . . . .

. . . . .


V8

Yeah, i'm just startin trash, that's what I do . . .

LOL!

But yeah, a 2.7 liter KADET . . . that is insane . . .we need more people on that level of tuning and building, think outside the box and have fun with it. That's what keeps drifting fun and that's what makes grassroots events AWESOME!

i luv the 2.7 KA in rhd s13 idea dude, GO FOR IT! cant wait for a biuld thread

just how mush boost will a 2.7l ka handle though?

OVER NINE THOUSAAAAANNNDDD!

i remember seeing a video of a rhd ka-t in japan and thought it was a pretty sweet idea. good luck with it.

I am hoping to boost 1.5 bar, but I would be happy to just boost 1.0.
The only part I will not have the money or time for is the head =(
I would like to be able to rebuild a complete head so I can get my top end back. But reguardless it is still a fun and bad-ass motor!

yea... you dont need mega boost with what the motor can do in N/A form.

:beer05:

Why stroke the piss out of the KA to 2.7liter, With a brian crower stroker kit?
2.6 is suppose to be the maximum tolerable for the KA block. I spoke with Brian Crower in person and was explained the frictional losses to the piston rings when exceeding 2.6 liter, not to mention the KA cast iron wallsbecome much to thin.


Anyway KA head is much more simple in design and meant for high rev, the SR engine unfortunately isn't. Bucket Hydraulic valve assembly> Rocker Valve assembly

KA is a heavy engine and sr is lighter each engine has it's pro's and cons

The motor is not exactly a 2.7 liter. I do what every car company in the world does. The 2.4 liter is actualy 2.38 or something like that, but they call it a 2.4 liter, My stroke and bore brought the motor up to a 2.675 or somewhere close to that so I just call it a 2.7. I have not exceded the tollerable bore or stroke. I spoke with Dustin at brian crower when I did the stroker kit about a year and a half or two years ago, and he said that I was still within the tolerances. I talked to my machinest as well and we went through his books and found the KA and its tollerances and there was no issue with the size of bore I was planning to go. I also plan on boosting it and building the entire head with brian crower parts. After every thing is said and done I will have plenty of power all the way up to about 7.5 - 8 thousand RPMs. the only downfall with the sroker kit on a stoc head was the powerband ended at around 5.5 thousand RPMs. that is where the turbo and the BC head will come in to play to compensate and then some.

Sorry it took so long to reply I have been too bussy working on the car and at work to get on the forum in a while.

good **** steve i cant wait to start on this..

The engine runs out of power at 5.5 RPM because the displacement is to large for such a small MAF. The hot wire cools so fast that the injectors are limited to peak duty cycle.

Increasing MAF diameter size shifts the K value of the ecu MAP over so that your CAS value can deliver more fuel.

Looking at your build "before turbo" you are using a stock header, that will also limit your "rev range"

So where did you get the custom pistons? Brian crower sells the kit as a 2.6 liter stroker and I believe that piston is custom with pin height adjustments for the shorter rod used. Pin height is also adjusted to reduce friction for high rev, so who do I get in contact with to get this special piston?

AAAAAAAAAAAAAAAAAAAAAND meet vinnie steve our NA KA GURU

Dude I'm just saying I talked to Brian Crower personally about this kit at formula drift.

At a 90mm piston bore that is already a.020 bore. For a 2.6 liter stroker.

At a 91mm piston bore that is already a .040 bore, for a little under 2.65 liters.


A 2.65 liter stroker is 6.495, or the equivelent of 2648cc's which is under what it would take for it to be a true 2.7 liter. It would have to be over 2655cc's to be considered a 2.7 liter stroker. I believe that is how the Japanese have rated it for years.
At .050 bore that would be 2.7 liters, and I don't believe that is possible on the KA block. I don't think brian crower or CP offer a piston that large. Als with any head milling that would probably be done you can count on your cc's being around 2580~2640cc's depending on your 90 or 91 mm bore size. Like I said these kits are not designed for 2.7 liter.

no doubt vinnie lol i was just telling steve all about your vast knowleadge bro... lol i can get sideways with a 1.2 liter if i had to HAHAHAHA.

man wish i had the money to do the 2.6L kit :( and just keep it NA, i think that would be pretty sweet personally

well if i ever come by $3K somehow that will be where it goes ;)

ps the car sounds awesome man

CP will make any piston size you request if you have the dimensions and of course money. It has been a really long time since I had the numbers in front of me. I need to research again but it has been about a year and a half since I did the build. I have been realy busy working on more inportant things than a hopefull motor build getting ready for JCI and repairs from my last drift accident. I snapped the passenger side (RHD) fender in half and broke all the mounts on the S13 headlight off. Just got the new headlight in and need to glass the fender back together. Need to get new tierod ends and a couple of other things. It might be only a 2.6 liter Like I said before it has been a while. I will get more details after JCI and after winter time. You seem a bit more inteligent than I am, Ihave only doneone motor rebuild in my life and the KA26/KA27 was the first. I was actually suprise that i was able to build the motor myself and have it start right up on the first try. I do know however that when I did the build everyone I talked to said it could not be done, but I got rid of every vaccume line on the motor except the fuel pressure regulator, but I rerouted it directly to the intake manifold. Thank you for your inputs. I will reasearch the numbers again and get back to you later on the stroker kit after winter. Pardon my spelling, my computer is sloer than I type and I cant spell to bgin with.

Not to be a jerk. But I simply don't believe you. First to get the specs you would have to buy the pistons from Brian Crower. He doesn't hand out patents for free.
Secondly CP doesn't offer a piston for an engine any higher than .040 bore. Never seen them any higher and probably never will since .040 bore keeps it within safe tolerances.
Third of all I've tried pistons which would be a .060 bore equevelant and stock rods using the VH45de pistons from the Q45. It doesn't work the walls are to thin between cylinder chambers. It poses cracking and fractures along the cylinder walls when it is bored and honed....
Fourth and for most spending all this money on a Brian crower kit and brag about it you would have pictures, and or a Dyno, none which have been presented for a $3500+ rebuild performance kit.
Not to mention I've seen these kits in action and they clearly make power to 7000+ RPM HP Peak, and you claim that it won't mke power over 5500RPM.
I'm calling B.S.

Thread Closed...

Wow, Vin, you close the thread without giving him a chance to reply?

Without mathematical facts, which we won't be getting. A dyno which we probably won't see. Or actual internal pics of the motor which we probably won't see. I have no time or patients to deal with blah blah.

This forum is designed to present information that could be useful, not wasted bandwidth.
If you want to leave it open go ahead. waste of internet IMO.

Extremely true, but alternatively, may I present that I see a lot of threads started (at least monthly) that - in that instance - should be closed. I find myself talking to a lot of new drivers who don't quite live up to the life in which they propagate. I don't close their threads, I just let them speak their minds and continue to disprove everything they say. Eventually, they give up, and I delete the thread.

Trust me Vinnie, I am with you 100 percent, you and I go back pretty far on S-Chassis and I look up to you as a veteran member, I just feel that we should give him a chance to at least 1.) come clean or 2.) present his side. If, from there, it goes into this huge, off topic or ranting/venting rampage, then yes, by all means close it. I just don't think it's fair to close it having only presented your case whether or not you're right.

^_^

-Dave

when i asked about the amount of boost it was an indirect question about the thinned cylinder walls. i'm a bit skeptical about the 2.7l claims but i'm willing to chalk it up to bragging rights or whatever. having an engine with a greater displacement that the already ample approximation of 2.4l would be something i'd brag about for sure.

It's just insulting to a guy like me that has been promoting the KA for years and pushed for the use of the fully counterweighted crank.
I spoke with Chris at AMS to get a fullycounterweighted crank pushed out in production.

Also when these cranks were in discussion Brian Crower brought out his crank the same year. This kit has only been on the market for the last 2 years, not 3+ years.

We all discussed the advantages of fully counter weighted cranks, and how harmonically it helps maintain smoother revs and higher redlines. Promotes a healthier torque and HP band as well. I don't believe power drops to 5500 RPM when the stock bottom end makes power to 5800 RPM, and the improved fully counterweighted crank would atleast promote peak power past 5800RPM.

Call me a grinch I just know too much about this engine and the parts available that to a guy like me it's insulting without facts.

I would just like to see this thread closed before it reaches 1000 views from members and none members and save us the embarrasement of misinformation.

I'm tracking dude, LOL! You are a plethora of knowledge and quite honestly, at least in my eyes, King of the KA! You've probably done more to make the KA something popular than any other ONE person can claim.

I feel the same way with motorsports, more over drifting, I'm out there at least once a month, busting my ass, struggling with my platform to learn, going broke, advertising, blah blah. Just to make drifting more of a household name in the minds of both motorsport and non-motorsport enthusiasts. Then I pop in and some non-driving rookie is trying to tell me that they know more about the sport than I or that they're a better driver, LOL!

But yeah, lets see what he has to say, he's on a completely different time-zone/date line than we are, so lets give him a chance to rebut.

-Dave

bros calm down.... i have physically touch the motor and seen the walls.. its no where near a 2.4 thats for sure..



in sieve's defense he is active and for what im worth and what i have seen him do, i validate him as a real tuner and driver.

he is new to forums and has not yet learned yet how to relay things. that is all

I'm not up at arms at all, LOL! I just want the thread to stay open ^_^

Did you see the crank shaft or pistons?

i held the crank it is indeed a BC crank. as far as the pistons to be brutally honest i just know they are not stock size 2.4L pistons.

I have plenty of pictures of th KA build, Click on my myspace link and go to the KA24DE-KA27DE pictures. You can see all the pics. Do not call me a liar, for I am not.

O.K well this is for sure what I am gathering from your build pics.

First off those are the 2.65 liter pistons from Brian/Crower.
The KA block is a siamesed block which means each sand cast portion for the cylinder chambers was individual molded together to make the KA24de block. A bore that becomes to large will crack the cast between the cylinder chambers. It would be nice if you could of atleast told the actual bore size of the cylinder walls.

Secondly your complaint about your rev and redline, is clearly your mistake with your build. Stock header is a no no, stock MAF is a no no, stock injectors is a no no. I could go on and on but those were the three identifiable parts to your build that would hold your engine from high reving.

Increasing your engine displacement means that you will need to increase the injector cc. You should just use the sr20det injectors with a tune or SAFC.
If the engine is only making power to 5500RPM your cut short on injector duty cycle /pulse width using the stock 270cc injectors, and your K value from the ecu.

Voltage fom the G60 MAF isn't helping you either, since you've increased your displacement your load value goes unchanged actually lowering your rev and redline. K value on the ecu has no where to go but to the right of the MAPS.

So in the process that you built this amazing internal KA you failed to upgrade the tune, injectors , MAF and headers so that you couldn't redline at about 8000RPM....


If you would like I have a book on ecu tuning. I have one for you that would explain where your problems are coming from. I can PDF the pages for you and send it via email. It's a good book with lots of answers.

Attachment 12392

I was running an entirely new fuel system, but I did have the stock MAF, and stock Header. I was running top feed 550cc injectors with an aftermarket fuel pressur regulator, and walboro 255lph fuel pump. I also was running an Apexi AFC II. This was the first motor I ever worked on myself and I have made mistakes with it, but for my first it wasn't too bad. I did not know that running the stock maf would hurt the powerband as it did. I thought that was just the head and exhaust manifold. I was planning on boosting it and going mafles, which I still plan on doing. MAP is the way to go, that and a new ECU (AEM EMS). I was dumb I agree with the stock headder and MAF, but I got a little ahead of myself. But I have learned from that mistake. I did not join a forum to piss people off, or make enimies, I joined to learn from other people, who know more than I do about cars. I had never been on a forum really. A feiw months ago I couldn't have told you what one was for the life of me. I would like a copy of the book. Thank you. I do have a question for you since you seem to know your **** with the KA, is there an upgrade for the oil pump?

A G60 MAF is highly restrictive not only is it limited to its voltage. It also measures under 48mm diameter from the center of the MAF. Stock Throttle body is 60mm so in order to not allow any airflow restriction to the engine the MAF should be in comparison the same size or slightly larger than that of the TB. I use an N60 it is a bit easier to tune with as far as it's voltage range, it is also slightly larger than the stock TB so I know that my intake system is working more like a velocity stack.

I don't agree so much with the use of 550cc injetors. ATOMIZATION of air and fuel is to stay lean and clean to make big numbers. Natural aspiration isn't like turbo charging where 550cc would probably be more necessarry since there is alot more cylinder pressure. Using 550cc injection and using only 30% or less of it's duty cycle only makes the spray pattern less efficient. If your HP goals are roughly 250 to 300HP you would be fine using 360~440cc injection.
There is less pressure needed on the fuel system the spray pattern is also more consistent, overall its effeciency, power, and reliability that should be your goals for your build. You should be tuning around your HP needs and reliable goals, not for goals that probably won't be met.

MAP is always the way to go, but the facts are tuning with a MAF from the junk yard for under $40 is cheaper than a brand new $150 MAP sensor, and a few hours modifying the manifold.

For me MAF or MAP doesn't matter any tune that you make still has values that have to be plugged in and in some respects yes, MAF's are limited.