How to tune a 240sx?

[unahanaretsu]

Hi, I'm pretty new to the tuning scene and just wanted to have a little input from you guys about tuning my s13. I've dropped in a ka24de in a 1989 s13 fastback. Had to take out the air conditioning. I have a limited budget about 5000 maybe a little more. It's gonna be a daily driver so i don't want to drop in a turbo. Reliability and mpg is important too. I really don't know anything about tuning the engine though. What are the weak points of the ka24de engine? What should I be working on? What should I work on with suspension and drivetrain? Are there components that I really don't need? For example I already took out the AC Unit should I change to a manual steering rack? Thanks for all your help guys.
Modified by unahanaretsu at 12:44 PM 4/25/2009

[duffman1278]

You have ALOT of reading to do.

I suggest you start by reading around on threads here on Nico and Zilvia.

And btw I highly emphasize ALOT.

Reading is power.....The more you know.

[j-z]

YOU are going to spend ALOT of money to get to 175 whp NA on a ka.... the best route to do that would be with ITBs, some sort of standalone (megasquirt), nasty cams, ported and polished head, a GOOD header ($$$$), bigger intake and exhaust valves, higher compression ratio (single cam pistons probably, or aftermarket....), electric water pump, anything to free up horsepower.... with some good tuning you should hit 175 whp. mind you this will cost you atleast $3k.... good luck

OR you can go turbo with a tuned ecu, and a s15 bb stock t28, and blow those numbers out the water for less money. your call.... boosted cars can be just as reliable as a NA motor. it depends on the parts you use, how it was put together, and most importantly... TUNING.

[unahanaretsu]

Yeah I've been scrounding around the forums but the information is hard to find and after I've found one the information becomes overload lol. If I could get a good starting point, which was my intention of this topic, that would be fantastic. To turboing it... I've always heard its really tricky to tune and not wear out the engine, and since I'm a noob, I was just gonna go NA
Modified by unahanaretsu at 1:27 AM 4/25/2009

[j-z]

my best adivce since youre a noob.... drive the car how it is, and read on here every chance you get. im not going to say that trying to get 175 whp out of a na ka is a bad idea, BUT why??? are you road racing the car? autox? anything? if youre just driving on the street, i think that is a stupid idea. it sounds tits, but think about it logically. doesnt make much sense does it?

also about your suspension question. i can full fill that for you. for starters go with a NAME BRAND coilover setup, or some good shocks and springs. the BEST bang for the buck are suspension techniques sway bars. tension rods are awesome, and so are new tie rods and ends. youll need RUCAs for rear camber adjustment, and rear lower tie rods for toe adjustment, AND camber plates up front if you dont go with coilovers for camber adjustment up front after you lower your car. a vlsd is a nice addition to the way the car handles as well.

another thing, you say you took out the ac, so you should put in a manual steering rack?? WTF? that doesnt make sense, unless you meant you took out the power steering. if you did that then thats one of the dumbest things you could possibly do. yeah you might free up 2 horsepower and .5 ft lbs of torque, but the advantages of having power steering easily out weigh of not having it to free up power. if you want to free up power, and have a cleaner looking engine bay get some electric fans and take your mechanical fan off.

[unahanaretsu]

I meant take out power steering and put in a manual steering rack. I've never had a car with power steering and I like how i can feel the road without it, thats why I was thinking about just scrapping the power steering and freeing up some horse power. As for why i wanted to tune it, even though its a daily driver. I just wanted to be something I can tune over the weekends, just for fun. I've always liked cars and thought that it would be nice to have a goal in mind while tuning.

[j-z]

post your definition of tuning on here for me. youre not making much sense. keep the PS btw.

[unahanaretsu]

tune - to modify your car and make it better?

[spooled240]

are you talking about engine tuning or just tuning in general?(suspension stiffness, alignment, etc.)

IMHO, going n/a is a waste of money. An n/a ka24 will hit about 175whp and a ka-t will hit 200 whp at 7 psi. Turbo engines can be reliable as hell when built properly and a ka24de on low boost (under 10 psi) is cakewalk.

Once you get a good tune for your engine, you won't need to change anything unless you are really anal and you want to correct for elevation and temperature changes

But a lot of guys run an AFC NEO or something along those lines to tune their ka-t's, sr20's, rb's, ca's, etc.. You can adjust a number of settings on the engine management using one of those, so that maybe something you're looking for.

Like some of the guys mentioned on here, do your research. If you know your stuff then you can select parts that will work perfect for your application and goals. example: Don't go and buy a huge a** t67 turbo cuz someone said so and run 6 psi of boost lol

[unahanaretsu]

Tuning in general. I wanted to first start off with the engine and up its horse power, and then move on to drivetrain and suspension. Ka-t with low boost sounds good now but what about lag issues? Would a supercharger be a better alternative? I was reading a lot about throwing an supercharger into the ka and it seems like less parts than throwing in a turbo.
Modified by unahanaretsu at 1:29 PM 4/25/2009

[Razi]

Supercharger would be good for what you want, if you know how to set it up.I have a turbocharged KA, lag isn't really an issue.

[j-z]

if youre going to mod anything, do the suspension and brakes first. trust me on this one. ive built plenty of cars before, and anyone else on here that knows what theyre talking about will tell you the same thing. you wont have ANY lag at all with a s15 bb t28. ive never ran a small turbo on a ka, but i have on the bigger honda motors. those turbos were straight t3s on just a weee little bit smaller motor (H23 = 2.3l vs 2.4l). i had virtually no lag with those setups. ill put $100 down for the same as the ka with a s15 bb t28. youll probably get full boost at 2500 rpms (edumacated guess.....) @7 psi if thats what youre going to run. although i believe the stock WG actuator is more than 7psi, but you can always take one off another turbo thats set for your desired boost level and retrofit it on the turbo. reason being is that you can not lower boost than what the wg is actually set to be at. you can turn it up, but can not lower it (same goes for external wg).

i would go turbo over supercharged for these motors anyday. its been proven 1000 times fold. ive only seen like 2 or 3 supercharged ka setups ever since ive been a member here. they wernt power houses either. it also depends on what kind of supercharger you go with. s15 t28> centrifugal unit.

with the s15 t28 bb turbo setup you can easily do. they already make bottom mount manifolds for it, turbo outlets, downpipes, and intercooler kits that are all over ebay for dirt cheap. i wouldnt skimp on the turbo though. i would get the real deal (buy a brand new one). on my KA-Ts ive always ran a t3/t4 configured setup with.63 ar exhaust housings and a couple different exhaust wheels. even with those setups, both log mani, and tubular, lag was there but nothing that will have you b****ing saying i want a smaller turbo so i can get going 500-1000 rpms quicker. once youre spooled, and slappin gears there is no lag. from a dig is where you get the lag, or passing someone to where you may have to downshift. lag is nothing until you start getting up to something with a t4 exhaust housing for these motors.

[unahanaretsu]

Hmmm I've decided to go with megan racing coilovers and z32 brakes. As for strut bars what would be the most important strut bars to replace? I've been reading up on this and it seems that T/C Rod Brace and C-Pillar Bars should be changed. Is there any other strut bars that probably need replacing? Also which brands would you recommend?
Modified by unahanaretsu at 9:36 PM 4/25/2009

[j-z]

go with sway bars before and strut/brace bars. those really dont do shlt anways.... if they did i wouldve mentioned them. a front strut bar will help a little, but save for sway bars first. they make your car drive like a go kart!! get some front tension rods, and tein inner/outer tie rods, adjustable RUCAs, and adjustable rear lower tie rods and youll be set!

[unahanaretsu]

What about the LCA for the front and back, Toe rods and traction rods?

[simmode1]

1) Complete all maintanence issues2) Enjoy the car stock3) Upgrade your suspension. The options are endless, but I would avoid the strut/shock/spring route and go straight to coilsovers.4) Upgrade braking system. Again, tons of choices. J30/Q45 brakes being the cheapest...5) Now you can consider power adders. Personally, I wouldn't even waste time on bolt-ons until you've committed to a certain upgrade path. Nothing short of swapping your motor or turboing your KA will ever make the car fast. Well, except for nitrous maybe...

[Nali]

tune - to modify your car and make it better?

Tune - to make small adjustments to a car to obtain the proper or desired performance.