Getting power out of an N/A KA

[Shin_Kudo]

In the 240 world, it seems there are often only two choices considered for increasing the car's power by more than a few HP.

First, and more common, would be engine swaps, with the SR, of course, most popular.

Second, and gaining popularity, partially in retalliation to the proliferation of SR-powered cars in the US, is the KA-turbo.

But there must be a third option. It is possible to improve on the natural power and torque of the KA24 without resorting to bolt-on mods like turbochargers.

As with any car, everything from cams to pistons has the potential for improvement, along with the mechanisims on the outside of the motor.

But what parts are actually available to improve the naturally aspirated power of the KA? And how is their quality, and their pricing?

My intent is for this thread to be like the SR and KA-T FAQs, but for those who prefer the response and design of an N/A motor.

[projectRDM]

You have done zero research if you're posting this.

At most you can get 260hp out of a KA, that's running very agressive cams, super high compression, and race gas. Everything typical of a bolt on street motor won't break 170hp. Period.

[Andrew Bohan]

i built a high compression KA, and it was much faster than a stock KA, but not as fast as my turbo FC.
but i fucked on the build of that motor and it only lasted 300 miles.

didn't get a chance to dyno it, but guys with similar setups had low 170's to the wheels.

moral of story: high comp KA is fast, but don't let me build it for you.

[Ghettokracker71]

Originally Posted by i'm driftaholic

but not as fast as my turbo FC.

Ghee...I wonder why? Lets see....the FC is TURBOCHARGED and lighterweight

[Shin_Kudo]

Originally Posted by R240NA

You have done zero research if you're posting this.

At most you can get 260hp out of a KA, that's running very agressive cams, super high compression, and race gas. Everything typical of a bolt on street motor won't break 170hp. Period.

Actually, I've been doing research for quite a while. I've found very little of use.

Why is it that an N/A KA can only make 170, when there are N/A SR20s pushing 250-300? Even with ITBs, upped compression, better fuel delivery, relatively agressive cams, and a whole system polished and engineered to flow air well, there's still now way to make real power?

Is it really true that the only way to get adequate power out of the car is to turbocharge it? I've never even driven a turbo, and I'm pretty reluctant to go with a method of increasing power that I'm so unfamilliar with.

[Brian]

Russ said most you could make is 260... not 170.

[atom]

Originally Posted by Shin_Kudo

Actually, I've been doing research for quite a while. I've found very little of use.

Why is it that an N/A KA can only make 170, when there are N/A SR20s pushing 250-300? Even with ITBs, upped compression, better fuel delivery, relatively agressive cams, and a whole system polished and engineered to flow air well, there's still now way to make real power?

Is it really true that the only way to get adequate power out of the car is to turbocharge it? I've never even driven a turbo, and I'm pretty reluctant to go with a method of increasing power that I'm so unfamilliar with.

Keep in mind he said typical bolt ons. So that leaves out ITB's, crazy cams, P&P, B&B, etc.

240 people are just more inclined to turbo so theres not a lot of info period. You can be one of the pioneers and post your results here.

[Phlip]

Originally Posted by Shin_Kudo

Actually, I've been doing research for quite a while. I've found very little of use.

Why is it that an N/A KA can only make 170, when there are N/A SR20s pushing 250-300? Even with ITBs, upped compression, better fuel delivery, relatively agressive cams, and a whole system polished and engineered to flow air well, there's still now way to make real power?

Is it really true that the only way to get adequate power out of the car is to turbocharge it? I've never even driven a turbo, and I'm pretty reluctant to go with a method of increasing power that I'm so unfamilliar with.

Pay attention to the operable words in his statement you were responding to, typical of a bolt on street motor, he has been one of the guys to get 170 to the wheels on a still streetable NA KA24DE... ITB setups are shitty in the cold weather, upped compression makes for a detonating and tempermental bitch in daily stop and go traffic, and damn near REQUIRE race gas, not worth the price of having the highest HP NA KA24 in my opinion. Better fuel delivery = higher fuel consumption, gas ain't cheap, Bush is in office. Agressive cams = lumpy idle and shitty emissions, plan on getting it smogged in CA? I'm agreeing with Russ on this one.

[sciamop]

If you like powerful, streetable NA engines, you have 3 options:

1) Domestic V8 (Chev 350, Ford 351)
2) Honda VTEC (Honda S2000)
3) SR20VE (not much info about this engine stateside)

As a side note, what's up with the FUD over forced induction? "Turbos scare me. I'd rather run a 20:1 hi-comp KA. It's much safer, way cheaper, soooo much easier AND I won't be jumping on the bandwagon with the rest of you idiots! Instant 300whp!"

Todd
90 Coupe NA
93 Coupe T

PS Read about Andrew's hi-comp engine build for some heartbreaking shit:
http://www.mountainracer.com

[projectRDM]

Thanks for the back up guys. I'll also point out that an SR will rev considerably higher than a KA, thus having a lot more headroom to make power, and is a smaller bore motor. The bore/stroke on the KA yields to a lot more usable lowend power, but runs out of steam by 7k RPM. The race motors used in Touring Cup generally are SOHC, running carbs instead of FI, and built/tuned for high RPM use.
Then you have to factor in cost. My old pig put down 158.8rwhp. Here's a breakdown of retail cost for the items that got it there:

Stillen hi-flow, custom short intake pipe- $200
S13 cams- $125
HKS Twin Power ignition- $420
Vitek plug wires- $130
Hotshot header- $300
RT cat- $200
Bee*R catback exhaust- $550
Meuller flywheel- $500
UR full pulley set- $480
JWT ECU- $600

The car also weighed 2520lbs, so yes, it was very fast and a lot of fun. However looking at the cost of $3505 (I paid considerably less, but that's a good baseline) and the strain of driving a car that was loud, noisy, hot, and generally all around uncomfortable as hell seems pretty stupid now that I look back. Now take into consideration the headwork, pistons, rods, and the added fabrication to make the motor capable of 260rwhp, you're easily doubling the cost if not more.

For the money I spent I could have easily gone with a nice, simple 8psi of boost, made more power (more than enough to offset the added weight too), and had a nicer car. That's the route I'm going with the new car.

[Phlip]

And to think, Russ, you almost had me convinced to go your route... In the S13, I will not have AC and will eventually be boosted, but I'll be damned if I go to the lengths you went to in the "hardcore lightweight" just based on the amount of bitching I have heard you do over the last couple months since it has been cast to the side.

[Doriftomodachi]

People here who are serious about improving the performance of their cars know that bang for the buck, in the long run, you will yield MUCH more power with a turbo setup because with a turbo achieving significant horsepower gains becomes a matter of safely turning up the boost. If you spend a similar amount for cams, headwork, etc. it becomes much more expensive and yields much less gains. My advice is to start saving for a turbo setup now or like it was said earlier, get an s2000 or 350z if you wanna stay n/a.

[wootwoot]

Originally Posted by Ghettokracker71

Ghee...I wonder why? Lets see....the FC is TURBOCHARGED and lighterweight

a 2nd gen rx7 is actually heavier than a s13 or s14 =P

[nightwalker]

there are a lot of options out there to making power. It's just the 240sx community is turbo biased so no one spends the time, effort, and money to go NA. The only reason I could see going NA is to not really get fucked with when you get your hood popped (California people). If I didn't live in Cali, I would be chucking KAs for SRs all day long.

Fortunately I live in this Nazi state so I've held back from go SR.

Maybe one day someone with motor building experience will properly test and build a nice DOHC KA.

btw guys, in relation to building motors, when asked about making power, everyone keeps saying that you should build the bottom end (e.g. high compression) but horsepower is made in the top, the bottom end is there to handle it. (if needed)

[wootwoot]

would porting the head of a ka24 really be usable though since most gains would be found high up and with the long stroke the ka cant go there easily?

[infinitexsound]

well rebello racing has been producing high horsepower nissan engines since the datsun days. many autox shops run that z24/12valve head, frankenstein motor..i think it pushes around 300 hp... but as for the ka i wouldnt know.. lots of ppl ive seen with the ka24de motor usually modify's the intake manifold to use a double carb setup..and have yet to read a article about how high u can push a ka24de to produce..

[Shin_Kudo]

I suppose I should have mentioned this: I'm running the car as a daily at the moment, but by the time this engine work is done, the car's gonna be a dedicated race car. Traffic, most weather, comfort, all those issues won't matter, as the car will never run less than 100 octane, and the only time it'll spend in traffic is on a trailer.

So I don't need streetable. I'm talking a theoretical N/A race motor.

On the streetable side, however, I'm talking much more than bolt ons. I'd like to hear what the possibilities are for making the best street motor possible. Plenty of cars run ITBs on the street. It's not really an issue here in Socal anyway.

I guess I have a little bit of the old-school muscle bias, because to me, Turbo just feels like cheating, almost on the level of nitrous. It can give powerful gains, but it's essentially something that's tacked onto the engine. I just really like the idea of improving the engine itself to make the power.

If it's really not practical to go N/A, KA-T it'll be, but I just would much prefer to do something original, rather than just bandwagon jumping.

[Phlip]

In this case, you need to say "Thank you, PHLIP, I am too fucking lazy to search and I greatly appreciate you looking for the thread that was easily found if I HAD looked for it..." Luckily, I posted a couple times in this thread a LONG time ago and will go as far as to lay out the search you may have committed yourself to doing and getting yourself a little further than you have gotten: http://www.zilvia.net/f/search.php?searchid=215356

[Shin_Kudo]

Dude, the search you link comes up with a no matches message. Everything I tried came up with the same, unless I used search terms so broad that I got 500 pages of threads.

[Phlip]

Dude, the first of those links takes you to an old thread I happened to remember, containing this picture of a 510 with a KA24DE with a side draft setup:

picture came from http://dimequarterly.tierranet.com/... Maybe they can help you on your quest to avoid boosting your car... Not worth it, in my opinion, NA horsepower will be an expensive bitch to create.
Now you have me on the search, I tried that link again and it took me nowhere, but it worked last night when I first posted it (I searched using the term "carburetor")

[sciamop]

Originally Posted by Shin_Kudo

I suppose I should have mentioned this: I'm running the car as a daily at the moment, but by the time this engine work is done, the car's gonna be a dedicated race car. <snip>

So I don't need streetable. I'm talking a theoretical N/A race motor.

A theoretical NA race motor? What is this a GT4 for the PS2 forum?

Originally Posted by Shin_Kudo

On the streetable side, however, I'm talking much more than bolt ons. I'd like to hear what the possibilities are for making the best street motor possible. Plenty of cars run ITBs on the street. It's not really an issue here in Socal anyway.

SoCal is a mecca for import car 'tuners'. You should stop in a reputable engine shop and discuss your plans with them. I'm sure they'd be able to give you a price if not a parts list.

Originally Posted by Shin_Kudo

I guess I have a little bit of the old-school muscle bias, because to me, Turbo just feels like cheating, almost on the level of nitrous. It can give powerful gains, but it's essentially something that's tacked onto the engine. I just really like the idea of improving the engine itself to make the power.

Modern turbo engines are engineered around forced induction. Lower compression, stouter pistons, stronger crank, etc. Nitrous is a true add-on.

Originally Posted by Shin_Kudo

If it's really not practical to go N/A, KA-T it'll be, but I just would much prefer to do something original, rather than just bandwagon jumping.

Bandwagon jumping? Judging by your *basic* understanding of hi-comp KA engines, you'd be much better off jumping on the bandwagon than getting run over by it.

Did you read Andrew's Hi-comp nightmare?

Todd
90 Coupe
93 Coupe

[orion::S14]

Originally Posted by Shin_Kudo

Turbo just feels like cheating......I just really like the idea of improving the engine itself to make the power.

How about reusing otherwise wasted exhaust energy to create more power...improving the overall efficiency of the system...?

That's definitely "improving the engine itself" IMO...

For a road race car, just for fun (not competititon)...I'd do N/A KA again. ~160-170rwhp is simple, easy, and reliable. Not the fastest out there, but the handling makes up for the lower power.

Now, my car is WAY more fun now with ~290rwhp (KA-T, T3/T4 @ 12psi), and is a BLAST to drive on road courses..but there's always the worry I'll kill the motor. I NEVER worried about that back when I was making ~160rwhp.

And my ~290rwhp setup cost less than any N/A KA that will be above ~185rwhp I'd bet...

- Brian

[Phlip]

Originally Posted by orion::S14

*snip*
And my ~290rwhp setup cost less than any N/A KA that will be above ~185rwhp I'd bet...

That's exactly what Russ said before, 158.8rwhp NA, at a retail cost of $3505... It would take a fucking IDIOT to NOT make 290rwhp or better with that kinda cash...

[nightwalker]

Since you live in Socal, I would research some reputable shops and have them do a proper flowbench test and port/polish with that. Make sure the same shop knows how to design cam profiles to make proper use of the head. Usually porting the intake manifold, and exhaust manifold is part of this process as you want everything to match. When tuning a NA motor, it's about matching and tuning harmonics, not just slapping a bunch of parts together.

A lot of people don't go N/A anymore because of the power available for cheaper with a turbo. But there are guys out there who still have the ability to do so.

A good example is my younger brother's civic that ran 13's with a SOHC EX motor, naturally aspirated. The motor was built by a shop in Socal. It's been a long time, and I forget exactly, but you can get it done. Like everyone has been saying, it will be expensive.

[Andrew Bohan]

My nightmare was the result of a few tiny mistakes adding up
like not bothering to check if the cylinders were round or needed boring out and bigger pistons. things like that. i think the motor would have been a success if i had been a little more wealthy and a little more patient.

on a side note, i mentioned that my high comp wasn't as fast as my FC so people don't get any delusions that it'll be ungodly fast. just considerably faster than a stock KA

[RBS14]

basic bolt ons = ~160rwhp for most dohc ka's.

I'm in the process of putting ITB's on my dohc ka, so I'll post up when I'm done with results. It won't be until next spring that I'll have results, so it'll be a little while.

The ITB's and making a manifold to put them on isn't the hard part. An ECU that can handle them is.

Also, there is a 298hp dohc ka that is run in some of the offroad nissan race trucks.

There is a lot more to building a high hp n/a ka than 99.9% of 240 people are willing to do, so this whole thread is kinda pointless. The people who are really going to build one are going to find out how to do it by other means that asking a stupid question on zilvia....

[Id-]

Originally Posted by sciamop

As a side note, what's up with the FUD over forced induction? "Turbos scare me. I'd rather run a 20:1 hi-comp KA. It's much safer, way cheaper, soooo much easier AND I won't be jumping on the bandwagon with the rest of you idiots! Instant 300whp!"

Todd
90 Coupe NA
93 Coupe T

PS Read about Andrew's hi-comp engine build for some heartbreaking shit:
http://www.mountainracer.com

ROFLMAO my exact feelings... why mess with it? turbo is cheaper, faster, more reliable

Originally Posted by Ghettokracker71

Ghee...I wonder why? Lets see....the FC is TURBOCHARGED and lighterweight

uh no... S13s weigh a good bit less than a FC... FCs are around 2800lbs...

big help that the FC has a turbo stock... a rather nice one i might add.... Hitachi with a nice 1.0 exhaust A/R among other things

[240sxconversion]

if u are looking for N/A u can always look into swaping a RB30 na, using a rb26 crank, get it balanced using 26 rods and 30 pistons give u a nice engine that will rev to 10k and produce nice horsepowe ( SO i am told, my rb30 is turbo so i dont know) research

[RBS14]

Originally Posted by R240NA

Stillen hi-flow, custom short intake pipe- $200
S13 cams- $125
HKS Twin Power ignition- $420
Vitek plug wires- $130
Hotshot header- $300
RT cat- $200
Bee*R catback exhaust- $550
Meuller flywheel- $500
UR full pulley set- $480
JWT ECU- $600

Saying you need to pay for all this stuff to get 160rwhp is a joke. First of all nobody EVER pays retail for parts. Secondly, you don't need an aftermarket ignition or an ecu to make that kind of power. Lets try again, here's what it's cost me so far:

cone filter w/maf adapter -$10
Custom exhaust 3" exhaust-$150
Catco 3" cat-$50
OBX header-$160
Aasco flywheel-$300
ASP pulley-$130
91 cams-$free
e-fan:$150

total: $950.00

A setup similar to this has proven to make ~160rwhp from multiple people, so don't argue that it won't yield that much power.

little difference between this and $3000+. Yea, you could add 100 for the cams, you are still at just over $1000.

[wootwoot]

Originally Posted by 240sxconversion

if u are looking for N/A u can always look into swaping a RB30 na, using a rb26 crank, get it balanced using 26 rods and 30 pistons give u a nice engine that will rev to 10k and produce nice horsepowe ( SO i am told, my rb30 is turbo so i dont know) research

thats what i want!!! but with vvti

itb's, high compression, i6, high redline.ooooooo yeaaaaa thats what i f'n want