NA-KA power

[ians240s13]

i recently got a 1993 240sx se. i plan to mod this car of course but i lack expeirence, i have installed a short ram intake and i plan to get 4-1 headers and catback exhaust. what are some other ways to get more power without completley rebuilding the engine. the car is my daily driver and i just want it to have more power.

[darens13]

headerS

[dgms240]

not a lot of power to be made on a na ka without spending a sh*t ton of money.
if you must do something to it now, start with the suspension. as far as the header goes, hotshot headers are really nice and combined with a N1 dual style exhaust, they sound great on a ka. if you want a significant power increase, just save up and do a basic turbo kit, the ka is good for 2-300hp safely without needing to build the bottom-end.

[simmode1]

Bro, tons of us have been there and done that. N/A KA mods are a total waste of time, IMO. You're never gonna get a streetable N/A KA to keep up with anything that's ACTUALLY fast like V8 Mustangs, BMW 135i's, 370Z's, etc...

If you lack alot of mechanical ability or tools or a place to do major work, SR20DET is the simplest way to go for power. No need to reinvent the wheel here.

But since you asked about N/A mods, here's what I know:
*Intake, headers & 3inch exhaust will give you some pep. 4-2-1 header is better for the KAde and 4-1 is better for the SOHC. You lose some of that low end torque that the KA is known for but you'll feel some gains in the top end.

*248/232 OEM cam swap is the best budget cam setup and will move your powerband a little futher up in the RPM range and give you a nice mid range power/torque increase.

*Remove the butterfly valves in the S13 KA's intake manifold or swap the manifold for the S14 KA's. This will give better airflow and a bit more power.

*Get a good clutch/flywheel combo & install electric fans from the Altima to reduce drivetrain loss as much as possible.

*Probably the trickiest mod in making a nice streetable N/A KA: Install a 4.636 final gear ratio. Acceleration will be improved quite a bit at the expense of top speed. Might wanna weld your diff while you're at it if drifting is your thing.

Aside from all that, get your suspension sorted out with some decent coilovers, arms and tie rods. Upgrade your brakes on the cheap with Q45 or J30 calipers. Get some four lug 17x9 wheels with 215/40/17 tires all around and you've got a little Drift King starter kit.

For all this hard work you might put maybe around 160hp to the wheels after a tune and just barely keep up with a bone stock SR20 swapped car, stock S2000's, etc. You'll be peppy or quick over short distances... but not actually fast. IMO, fast starts when you have 100hp for every 1000 lbs of weight. So about 280whp is the starting point for fast in the 240sx, IMO.

[alms24sebring]

^ good advice

A turbo is the best way to make the most power if you have a few thousand $$ and it doesnt have to be the biggest and best of the best. At the same time stay away from the $800 ebay kits. Why cant turbos be free?

[pella]

Simmode- what kinda options do we have for changing out that gear ratio?

[simmode1]

the-ultimate-final-drive-gear-ratio-thread-t228683.html

http://www.nicoclub.com/Greg/ratios.html

I'd prefer 4.363's for mild SR's and 4.636's for N/A KA's. Strictly an opinion though.

Keep in mind, your gears will be shorter. That means more shifting & higher RPM's at highway speeds, so your gas mileage will decrease.

Here's a fun little tool to play around with too:
http://www.240edge.com/performance/top-speed-calc.html

[pella]

Thats helpful. Where can I get different gears?

[simmode1]

Different gears? Let me clarify that comment. I think you mean different ring and pinion sets. We're not changing the gears in the transmission, just the ring and pinion in the LSD.


They are what determine a car's final drive ratio and how fast you go through each gear, effectively "shortening" them & in turn, reducing your top speed.

The links I posted showed just about every Nissan LSD and what it's Final Drive Ratio was.
-Find that model car with the Final Drive Ratio you want.
-Pull it's LSD/differential, take it's ring & pinion out.
-Pull your current LSD/diff out & swap ring & pinion sets.

Or you can just buy your desired ring gear & pinion from some vendor, like Courtesy Nissan or something. This would be a good time to weld your diff if you're into that kinda stuff. This kinda work shouldn't be too difficult for most mechanics to do but I haven't found any DIY write ups on it yet. The FSM should probably be all you need to walk you through it...

[ians240s13]

But since you asked about N/A mods, here's what I know:
*Intake, headers & 3inch exhaust will give you some pep. 4-2-1 header is better for the KAde and 4-1 is better for the SOHC. You lose some of that low end torque that the KA is known for but you'll feel some gains in the top end.

[ians240s13]

why are 4-2-1 headers better for the ka24de? headers where the next part i was planning to buy along with a full exhaust. i was looking at either a apexi n1 dual or hks hi-power any information on these exhaust systems? i have heard sound clips but im aware that computers don't do these exhausts justice. also i am not sure as to where to buy good headers or what brands can be trusted

[240TKE128]

personally i use a 4-2-1 on my SOHC and it works great so a nice jump and didn't really lose any torque noticeably maybe if dynoed it might be more noticeable. but all in all it works great im running, injen short ram, hks headers( i think cant remember been 3 years), and n1 style ebaby exhaust, not sure brand didnt care just got cheap cause im going to turbo the car later anyway. pretty decent setup all in all not bad even with a oem replacement clutch nice torque and did notice some extra power.

[simmode1]

4-1-header-vs-4-2-1-header-t230334.html

I once read an article in Import Tuner or something that backed this up. But I think you missed the more important point that headers don't really make any real or noticeable power. They just kinda move your powerband around. We're about about like 5hp gains here and some more noise.

[240TKE128]

4-1-header-vs-4-2-1-header-t230334.html

I once read an article in Import Tuner or something that backed this up. But I think you missed the more important point that headers don't really make any real or noticeable power. They just kinda move your powerband around. We're about about like 5hp gains here and some more noise.

That thread makes alot of since, because my entire intake and exhaust system was full of holes and rusting i didnt really research into anything myself before switching it out.

But with the turbo setup ive been planning that out for 2 years so ill be better this time around.

[simmode1]

I do wanna add that, man. I've been where you're at. I had:
-AEM intake
-OBX 4-2-1 header
-3 inch exhaust
-248/232 cam swap
-exedy clutch w/fidanza flywheel
and some other stuff.

At first, you might feel that your car is getting faster. But go test drive something with at least 300hp. Your definition of "fast" changes at that point. When I did that, I realized that any power mod that wasn't gonna get me close to that performance was a waste of my time, money & effort. I decided to turn my focus on my suspension, brakes, wheels/tires until I could afford the power I wanted.

[240TKE128]

Ill agree to that my buddy had a silvia conversion coupe with an sr swap, (before he wrapped it around a tree) had about 250 or so at the wheels, that was an amazing difference compared to my HB, but the KAT will fix that.


On a different note ive heard of people upgrading the plenum for NA. I Know its not really needed till your pushing 500hp but ive seen a thread or two around it, in my looks for it ive come across really 3, but its xcessive, Gato, and Godspeed.

xcessive
http://www.xcessivemanufacturing.com/on ... 109&step=4

Gato
http://www.ojperformance.com/Online%20S ... 277&page=1

Godspeed
http://www.godspeedproject.com/store/in ... ts_id=1484

Ive never used any godspeed products but ive seen plenty of parts they make. Let me know your opinions if there decent it might be worth doing on an NA setup as well.

[ians240s13]

so i get what your saying. building a na ka is not really the logical thing for gaining power. but would it be worth it to get new cams, cam gears, s14 intake manifold as well as headers and full exhaust? just until i could afford a good turbo kit.

also is there a downside to removing the butterfly valves from oem manifold?

[240TKE128]

Personally i would say dont waste your money on Na Parts if your going to get new cams, and internals then make sure you go ahead and get durable enough ones for boost. Outside of that i would just save up for your turbo application.

As far as the butterfly's i wouldnt know i havnt done it myself.

[biggie]

True, NA KA only feels fast until you drive something with more power.

My Vert has most bolt-ons and feels slow as hell.

[OutToWinPAHC]

You can go nuts and build an 18:1 nitro-methane NA...... oh but were on a budget here.

[simmode1]

so i get what your saying. building a na ka is not really the logical thing for gaining power. but would it be worth it to get new cams, cam gears, s14 intake manifold as well as headers and full exhaust? just until i could afford a good turbo kit.

also is there a downside to removing the butterfly valves from oem manifold?

I haven't removed Butterfly valves myself, but there's lots of threads on the topic. Just google 'removing butterfly valves ka24de'. Seems you lose a tiny bit of torque around 1500rpm but gain even more top and your idle sounds like you're running bigger cams. Apparently, Nissan agrees that the valves aren't necessary because they took them out of S14 manifolds. More direct air flow is always a god thing, especially if you're planning on forced induction.

As for what mods I'd get? I wouldn't any of those. At least not yet. I'd focus on maintanance, then suspension, brakes, wheels & tires. THEN I'd decide the scope of my build and whether to stick with the KA or go with the SR. I had always been a huge fan of KA-T or VQ. That is until my KA actually blew and I was forced to really put my money where my mouth is. At that point, I finally understood why so many go SR. To do KA-T right takes alot more work and cash than most ppl really consider.

[biggie]

Remove the butterflies vs S14 intake mani. The S14 intake mani will have different sensors/connectors when compared to the S13 harness.

Yes KA-T can get expensive. I started collecting parts for turbo in '03 or so. Finally got it running in '10.

[OM3GA]

NA KA's are fun unless you are looking for a ton of power. They definitely have their place though. I ran the above setup for about 4-5 years, it had great mid-high range power but nothing extraordinary.

Simplicity is nice and the fact that it is clean makes you feel much better about it.

[simmode1]

Excellent point, Omega. There's definently something to be said for simplicity. As long as you don't set your goals too high, I suppose theres no reason you can at least have fun in a N/A set up like this. Especially at drifting, don't need much power for that. Just don't get into any races with GT Mustangs or whatever thinking you're not gonna get your doors blown off....

[Idahos13]

I have heard that doing the 248/248 cams helps with your power.

[simmode1]

248/248 give you the most top end out of all the OEM cam swaps, but you lose alot of low end in the process. More than I'd wanna sacrafice.

248/232 only loses a little low end comparatively & won't give quite as much top end either. But its give the most mid range gains and broadest powerband of the OEM cam swaps.

You might wanna talk to the guys in the KA-T forum about which one they consider to be best. Both setups have their pro's & con's.

[OutToWinPAHC]

I have heard that doing the 248/248 cams helps with your power.

Higher lift, for a longer time let more air in, more air in allows for a greater compression force.

[kingtal0n]

displacement always wins. And by displacement, I mean theoretical displacement.

Whats that? 2.4L KA? Well my sr20 is 4.0L. it starts off at 2.0, but I add exactly 15psi of 100% efficient boost (real world = 18psi proper) and I wind up around 4L of displacement.

Well, hang on, if we do the same thing to the KA 2.4L engine.... AH but we cannot. Well, WE CAN but it will not be as cheap/effective/reliable, so it doesnt count.

Dont take my word for it, try it and find out.

[darens13]

248/248 give you the most top end out of all the OEM cam swaps, but you lose alot of low end in the process. More than I'd wanna sacrafice.

i have this setup plus a lightweight flywheel and i dont think think there any cons to it at all. i noticed no (noticeable) loss of low end power. its really not much different than stock. at 4 teeth ccw the idle sounds just like stock and drives like stock, at 3 teeth ccw the idle sounded awesome but was a little undriveable at low speed (parking lots, speed bumps) and had a tendency to stall.

[nifares240]

get the JWT S1 cams they are great for mid and a bit of top end.
a decent, basic, NA build is still fun.