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pulleys.. underdrive vs overdrive and risk factors?

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Old Sep 15, 2009 | 10:33 AM
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pulleys.. underdrive vs overdrive and risk factors?

okay so i read the NA KA build for 200hp cheap and was thinking on doing something similar. Though I don't mind putting in more money. I always read about pulleys being the biggest bang for your bucks and stuff like that. Now what are underdrive and overdrive pulleys? Differences, pros, cons, risk factors? Yeah i was reading up as i was looking into more information and people are saying its not good for engine life and things as such. Though they were talking about Hondas, figure it probably applies to all engines. Be great if someone could get back to me on this b4 i make a decision. Oh yeah and what all goes into installing the pulleys and all cuz i'd like to know so i can be ready to pay the shop or something. Oh and an estimated price on shop installing would be nice too. Thanks.
Old Sep 15, 2009 | 12:38 PM
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200whp NA KA is not cheap

requires alot of head work which is not cheap
Old Sep 15, 2009 | 12:50 PM
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Why do so many people think you can get these poor little engines up to "big boy" numbers on the sly when going NA?

You want big NA power, go with a bigger engine, otherwise, boost is going to be the only way to "save" money and make power.

-Dave
Old Sep 15, 2009 | 01:04 PM
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im confused.. are you asking about crank pulley. they will not yield much.
Old Sep 15, 2009 | 02:51 PM
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yeah crank pulleys
Old Sep 15, 2009 | 02:54 PM
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light weight flywheel > crank pully

you want to make your KA reliable and have more power on the cheap then get a turbo

simple as that now go do it
Old Sep 15, 2009 | 08:21 PM
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define "cheap".
Old Sep 15, 2009 | 08:59 PM
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Originally Posted by jramosthe1st!
define "cheap".
cheap as in u can turbo you KA for under $1500 and make 200WHP+ but making 200WHP+ with NA is gona cost you ALOT more
Old Sep 15, 2009 | 09:22 PM
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okay sorry for the debate, uhmmm i just wanted to know more about pulleys really not saying im going to 200hp cheap... n i mean more so affordable... but i just want some upgrade tips on NA so im asking about pulleys to get some knowledge
Old Sep 15, 2009 | 10:45 PM
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Originally Posted by battosaii930
cheap as in u can turbo you KA for under $1500 and make 200WHP+ but making 200WHP+ with NA is gona cost you ALOT more
i was actually asking the ts for what he considers to be cheap, but yeah big na hp is not as cheap as forced induction.
Old Sep 16, 2009 | 03:09 AM
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Underdrive is when the crank pulley is slightly smaller in diameter and because of such the accesories, alternator ps pump etc don't turn quite as fast. The pulley is also made of a lighter material usually aluminum, to reduce rotating mass for better performance. Overdrive pulleys would do the opposite, but could still be made lighter and just run the accesories faster.

Someone thank me for getting this thread back on track lol.
Old Sep 16, 2009 | 03:54 AM
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Thank you.... do you have a sister that is just as smart as you... Im single.
Old Sep 16, 2009 | 08:07 AM
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Cool beans, thanks. Now what is better out of the 2 and risk factors. Is it even worth an upgrade? I know forced induction is what everyone is saying to go for but don't got that kind of money yet. Just wanted simple upgrades.
Old Sep 16, 2009 | 09:02 AM
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Originally Posted by plat
Cool beans, thanks. Now what is better out of the 2 and risk factors. Is it even worth an upgrade? I know forced induction is what everyone is saying to go for but don't got that kind of money yet. Just wanted simple upgrades.
Okay, this is why the thread gets off track, you don't know what you want to talk about.

Do you want cheap bolt-ons or do you want HP numbers?

Cheap bolt-ons will NOT . . . and I repeat will NOT give you even marginal gains.

You are looking at 2-2.5 inch exhaust from the headers back, cold-air intake, and underdrive pulleys as your best bet.

The ONLY reason you would want an OVERDRIVE pulley is if you're attempting to run some CRAZY sound system and your UPGRADED alternator and ultra thick wiring with capacitors isn't quite doing the job for you. Basically, overdrive pulleys will not give you performance gains, if anything, they'll become more parasitic.

NOW!

You mentioned 200hp, not possible with what you're talking about. You're not going to get 200hp, NA on a KA without some serious and seriously expensive work. So go ahead and get that out of your brain.

Now, if you're talking about 140-150whp, then you can get setup with what I mentioned above (intake, exhaust, pulley and maybe even a chip).

If you want AFFORDABLE horsepower that will not kill your bank and give you bang-for-the-buck . . .boosting your KA is the way to go.

-Dave
Old Sep 16, 2009 | 12:29 PM
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well thanks, in anything just want to get educated about this stuff. I was reading the stuff by bigvinnie in the NA Motor section.



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