Under Drive Crank Pulley For KA24DE?

[Mr240dude]

What's up guys, so I was doing some research on under drive crank pulleys and was wondering if they yield any positive results. I've read that they are much lighter at the crank and decrease parisitic drag. Is it worth investing in one? I read that the accessory pulleys are not worth it but the under drive is worth it more. I've also read that they increase redline speeds as well. Are there any known issues to installing an aftermarket under drive pulley? Would it effect my accessories in anyway? Here's the one I was looking at b vision motor sports...


http://www.ebay.com/itm/390340225654?ss ... 1423.l2649

[numbnuts240]

do it, it'll be awesome.

[krash]

What does the rest of your setup look like? An underdrive pulley isn't going to get you anything that you will notice IMO. The problem with cheap underdrive crank pulleys is if they aren't balanced well, then it could cause premature wear on stuff. Maybe minimal wear, but its unnecessary.

[Mr240dude]

Well I have intake,performance spark plugs,header,test pipe and 3 inch exhaust. This once seems convincingly good quality. So you think it's worth it?

[Razi]

Is this a street car?
Why do you need an underdrive pulley?
It's going to underdrive all your accessories, and most importantly, your water pump and alternator.

Plus, it's also solid aluminum, so it can't dampen the harmonics like the stock pulley, which on a motor like the KA (Motor with a half-balanced crank), is important for longevity.

[Mr240dude]

Hey krash your post deleted for some reason can you post it again? Razi yeah it's a street car, I just wanted to keep it all motor since the turbo idea isn't realistic right now. So you're saying this isn't a good idea?

[Razi]

For the minimal gains (If there even is any), it isn't worth it.
If you want something that'll make a big difference, buy an aluminum driveshaft. I think they're about 10 lbs lighter than stock. It's very costly though.
It's very hard to make any extra power with just N/A bolt-ons on a KA.

[Mr240dude]

Maybe I'll look into the drive shaft. Well I've seen a lot success stories with people running NA yielding hp in the 160's to the wheels. Extensive engine work perhaps?

[asoomal]

The only crank pulley that should be on is the OEM one or the ATI Damper.

You will chew through front main seals with aluminum under drive pulleys.

[krash]

Weird, I can still see my post.

Like Razi said, you'll gain a lot more from doing an aluminum driveshaft. Its really hard to squeeze N/A power out of a KA. There is a member on here that spent thousands of dollars and a lot of time on his N/A KA, he's making about 200whp. It is an awesome accomplishment, but if you don't have the funds I wouldn't bother with it.

[Mr240dude]

On the contrary I'm content with a little kick to my DD 240. I'm not looking for 200 hp right now. I'm satisfied with full bolt ons and maybe some cams since I've also heard those can add some ponies too. Turbo is cool and all but it's not realistic as of now.

[krash]

IMO, Turbo is the only way to go with the KA. Cost:Power ratio is a whole heck of a lot better with ka-t than it is for an N/A KA. Razi has probably the best DD ka-t setup I have seen and in reality its not all that more expensive than doing an SR swap.

Anyway, if you're just looking for some pep, try an aluminum drive shaft or lightweight flywheel. Between the two, I'd probably choose the driveshaft first. Give the car a nice tune up, seafoam it, and it should run very nicely.

[dickie]

krash is right. f*** throwing bolt ons at a stock KA. unless you're bolting on a turbo. you could easily spend a few grand and you'll still be slow. performance spark plugs? no such thing man. intake probably isn't doing much for you, might even be hurting you.

don't even bother with the driveline stuff, that's money better spent elsewhere.

sounds like you need to spend some time getting knowledgified OP. do some lurking and learn from others' experiences; that's the primary benefit of forum cruising. i have a car that responds waaaay better to lightening/bolt-ons than a 240sx. i'd drive right past you in pretty much any situation with your current and planned mods and i'm still painfully slow by modern standards. if i had the foresight, i'd have saved my pennies for a turbo.

[dickie]

also: 240sx section.

[krash]

yea, didn't realize it was going to get all profound up in the hizzy. Moved.

You still working on the X8 d!ck?

[krash]

Also want to add, things like pulleys, lightweight flywheels, driveshafts, etc DO NOT INCREASE power. They just free up lost power.

[dickie]

yeah, getting it back on the road after a clutch fork mishap. the miata has actually been getting a lot more attention lately though.

[liquid_cool]

never use an underdrive pully with the ka24de unless you have a fully balanced crank..the oem crank is what they call half balanced..the oem damper helps save the all important bearings from the devistatingly destructive forces of harmonic vibrations the ka24de is famos for...save the coin and use it where its most benificial..good luck

[CCurate]

I have say to forgo the pulley. i have had one on my car for like 7yrs.its ok but you will DEF notice the vibrations from the engine. I need to replace it. plus noting to at least absorb a little vibration. I also have the aluminum driveshaft and flywheel. best purchase made next to my BRM exhaust. If your gonna have someone install the flywheel then i would by both before this way u can save on install as the driveshaft will be taken out anyway.

[RiverCitySX]

I had an S14 N/A, dynoed at 170whp. Only mods were injen cold air intake
meagan racing header and 3" straight pipe exhaust
pulsestar plugs
driveshaft shop aluminum one piece drive shaft
advanced base timing to 24 degree BTDC
I was pretty happy with it.
Then I joined the dark side lol