Longer gears in KA24DE??

[punkrocker7788]

ok, i will be the first to say that when it comes to gear ratios, and all that 4.125 3.21563... i DONT understand that bull.. I have an apexi 3" exhaust and going down the highway is pure HELL! the majority of the speed limits are 65, and at 65 the only thing you can hear it the exhaust..

I rode in my friends racecraft mustang 5-speed, we were goin 80 down the highway and it was sittin on 2k rpm.. HOW DO I ACHIEVE THAT!?

I have a 5-speed KA24DE, with a s15 lsd. do i put in a longer final drive? or what.. and i dont want all those freakin numbers please!

[goldfish]

If your problem is the noise of the exhaust and not fuel consumption or cruising at a higher rpm than your friend... why don't you modify the exhaust to be more quiet? Add a resonator, get one bigger than your current one(if you have one). The gear ratio bit shouldn't be the first thing you look at changing to decrease the noise. You'll hate the acceleration of your car if you change your gearing...

Change your exhaust and/or sound deaden your interior. Even just one layer of fatmat or whatever you want to use on your floor boards will help.

[carkook]

I think what hes saying is that he doesnt like being in high rpm's just to maintain freeway speeds. The only way to achieve lower rpm's is swap a different transmission with different gear raitos, or change the final drive in your diff. The lower the number the higher speed you will attain with lower rpm's. But as stated above your accelleration will be crap.

[punkrocker7788]

Your right! i dont like sittin at 65 mph and the rpm to be around 3k.. just annoying, i dont mind the noise, although it does get a little annoying sometimes, (seems to be more quiet when i go 75 rather, lol). But even if i just changed the final gear it would still kill my accel?

Like i already said, i have the s15 diff, shouldnt that have made a difference? haha, the diff make a diff?? sorry.

[carkook]

Im not sure what the final drive ratio is on the s15. But yes if you change your final drive it will change your accel.

[punkrocker7788]

So what your sayin is im pretty much screwed??

[goldfish]

So what your sayin is im pretty much screwed??

Just slap on a nice turbo setup and all the extra power with the different gearing will even out You'll accelerate faster because of the added power and won't notice too much additional lag.

Easiest way to change your gearing is to use oversized tires in the back. But that won't make too much of a difference. If you're primarily concerned with the noise, fix the noise issue. Otherwise changing the gearing will IMO... 1.) suck2.) cost more than a muffler shop changing the resonator or adding one3.) just like #1, will make driving the car not as fun

[ThatSRguy]

Im pretty sure the s15 lsd has a really tiny final gear ration you could always swap out that for a j30 rear end

[carkook]

Im pretty sure the s15 lsd has a really tiny final gear ration you could always swap out that for a j30 rear end

A really tiny gear ration? This makes no since, If you mean as in low I would say your wrong considering that would make good top speed/bad low end.

The higher the number the more agressive it will be at low speeds but then be high rpm's on the freeway. The lower it is the more top end you will get and less accelloration.

So for what you want your going to have to find a final gear ratio that compinsates for freeway speeds but sacrifice low end torque.

[ThatSRguy]

tiny as in it has a lower top speed a j30 would have a higher top end ie bigger

[1KleenS13]

You can change your 5th gear ratio, but you have to crack open the gearbox to do that. Or get a slightly taller gear for the rear. Or put a quite exhaust on the car

[carkook]

tiny as in it has a lower top speed a j30 would have a higher top end ie bigger

Except a smaller gear ratio would result in more top speed.

A j30 has a 3.92 final drive ratio and an s15 diff has a 3.62. So a J30 diff would result in better low end and worse top speed then what he already has. This is taken from the Ultimate Final Drive Ratio thread(zerothread/228683).

Go do some research of your own before you start trying to help.

[punkrocker7788]

damn thats alot of info to take in, as for the turbo, i bought the car and the existing KA had been overhauled and now.... has about 43,000 miles. so im gettin a turbo this summer, im doin my research and pricing everything, and considering a DIY..

What im really tryin to say is the noise is ok, i love my exhaust, and i dont wanna sacrifice the low-end POWA, ( i wanna see a civic accel up a hill in 2nd goin 15 mph! for real, i wanna see one.) I just want to be able to go FASTER. I want to keep my s15 diff cause its special to me lol, I just want more of a range in 5th.. know what im sayin? haha

[punkrocker7788]

and plus i dont really like cruisin down the highway at those high RPM's....

[Azrial]

get a nismo 6 spd transmission

[onosqv]

I rode in my friends racecraft mustang 5-speed, we were goin 80 down the highway and it was sittin on 2k rpm.. HOW DO I ACHIEVE THAT!?

Swap in a v8... Everyone's already given you the only "feasible" answers - i.e. swapping your final gear ratios, which will lead to crappy 5th gear, etc.; or get a quieter exhaust.

Engine, transmission, differential - you need to modify at least one to get down to 2k rpm on the highway...

Another small modification you can do is to get bigger tires - i.e. you'll be going 65 when the speedo reads 60. Of course, your car will look a lil ridiculous & overall acceleration will suffer, but your original goal of "2k rpm @ 65 mph" is already pretty ridiculous.

[punkrocker7788]

Thank you gents, i no have the info i need... FU*KED. hahah, oh well, it was worth a shot. anyway, thanks for the help, and modest support. lolol

[liquid_cool]

So what your sayin is im pretty much screwed??

im curious...you bought a 240sx with a 3inch exahust for what reason..to silently drive down the free way in an over drive gear at low rpm?..or did you buy the said 240 for a possible racing platform as it is a provin platform for Drift, Drag< autocross /Road, Touge....couse if ya was a REAL fan of the car you would be thinking of getting shorter ratio gearing ..like the do for RACE cars...with that said....remove the sound impuning stainless wonder of fun and add a stock P.O.S. exahst to it and be done..no more noise..no more fun...and when granny passes you ..you can yearn for your younger years of fun load enjoyment..and exceleration.....now that my sarcasim is over with...i hope you choose the fun side of this rant.good luck.

[punkrocker7788]

liquid, i like you style of thought brother. f*** the high rpms, that what my car was f***in made for! (p.s it had a s***ty exhaust when i bought it, i got the apexi 3").. Thank you for the slap of realization brother..

[liquid_cool]

liquid, i like you style of thought brother. f*** the high rpms, that what my car was f***in made for! (p.s it had a s***ty exhaust when i bought it, i got the apexi 3").. Thank you for the slap of realization brother..

np brother..welcome back to reality...we may not have high reving engines..but what we ka folks lack in RPM's and HP..we make up for in skill and Johnson size! ..with all the kidding aside ...there no high rev engine..but they are turbo happy to the core!...racing fast ina strait line dosent really take talent "untill your under 10 second Quarters" but making a rite hand corner at 45 miles an hour does..have fun man..and rejoyce in the fact that your car..will allways be desireable and colectible..while his P.O.S. is just like the rest of them..made to last 5 years then BOOM!..junkyard.