klze underdrive pulley

studboy13 · Post by **studboy13** » August 16th, 2007, 3:26 am

im getting a klze in a few days, i want to put in a lighter underdrive pulley while i already have the engine out, which 1 should i go with. and tips

mx3autozam · Post by **mx3autozam** » August 16th, 2007, 4:52 am

Unorthodox for sure. Or Cosmo racing, its the exact same thing and alot cheaper. stay away from OBX, i heard a few stories about those.

Mnemonic · Post by **Mnemonic** » August 16th, 2007, 6:48 pm

there are stories already about the lighten underdrive pulleys already, that 1 they dont increase performance but hurt it, or they will throw your crank all out of balance, blah blah blah, i never had any problems on the last motor i had mine on. another issue is because they know longer have some balanced thing on it (cant remeber the exact name) but if you get the UR one they have a piece on there that helps stabilize it, the obx one does not, which is where i think all these stories came from.

ScooterBovine · Post by **ScooterBovine** » August 17th, 2007, 1:58 am

I understand the concept of the underdrive pulley, but is it really worth it? I mean, all your accessories are going to be running with less power in exchange for a little bit more engine power is what it comes down to. And this includes the alternator. And the water pump? I mean, wouldn't it be better to just remove the A/C compressor to free up some pulley power? Then you wouldn't compromise the other items that you, in my opinion, really need.

mx3autozam · Post by **mx3autozam** » August 17th, 2007, 2:02 am

Some people say they have issues with the lights dimming at idle. I ahve the 110amp alternator so I have never ahd an issue. Even when I was running with the orogianl 90ampmx3 alternator it was still fine.

The only thing I would be worried about is spinning the waterpump slower than normal. I think it spins it 15% slower. I've been thinking of making a smaller pulley for the waterpump. I don't think its going to make a difference.

Mnemonic · Post by **Mnemonic** » August 17th, 2007, 6:29 pm

i would think you would be running more power, the pulley is slightly smaller than the stock one, if anything it would spin faster creating more power, that was always one of the concerns actually that the speed it spins would burn out the alternator. I never really had an issue with lights diming at idle or at all, a good battery should insure this doesnt happen

mx3autozam · Post by **mx3autozam** » August 17th, 2007, 7:19 pm

Mnemonic wrote:i would think you would be running more power, the pulley is slightly smaller than the stock one, if anything it would spin faster creating more power, that was always one of the concerns actually that the speed it spins would burn out the alternator. I never really had an issue with lights diming at idle or at all, a good battery should insure this doesnt happen

a smaller pulley on the crank woild move the accessories slower. smaller pulley on the alternator will spin it faster.

Hint the word "Underdrive" your underdriving the belts.

Mnemonic · Post by **Mnemonic** » August 17th, 2007, 8:02 pm

hmmm, well at any rate, i never had any of the "issues" that come with using them.

mx3autozam · Post by **mx3autozam** » August 17th, 2007, 10:04 pm

yep same here

it doesn't underdrive the accesories all that much on our cars. but other cars i believe it can.

studboy13 · Post by **studboy13** » August 27th, 2007, 11:38 pm

is the performance gain noticable?

mx3autozam · Post by **mx3autozam** » August 28th, 2007, 12:10 pm

dunno..When i first put mine on it was with my ze swap and Fidanza flywheel. so ya I noticed a huge gain.lol

Some people say it is noticeable. i think i read somehwree it was a 8whp gain proven. But I really don't know if I believe that or not.

timpronk · Post by **timpronk** » August 31st, 2007, 10:26 pm

I just installed the unorthodox pulley on my ze. I notice a difference in performance. Chirping in third a little more, with big heavy 17's

Response to throttle input feels quicker.

Just as a side note, the power steering belt unorthodox racing says to use, is a bit long. Will have to get a shorter one.

I say get one if you can, not a bad mod for $60 for used pulley + $40 for the belts. Took about a hour 1/2 to grind and install.

Have to see how it goes in the long run.

mx3autozam · Post by **mx3autozam** » September 1st, 2007, 4:52 pm

timpronk wrote:I just installed the unorthodox pulley on my ze. I notice a difference in performance. Chirping in third a little more, with big heavy 17's Response to throttle input feels quicker.

Just as a side note, the power steering belt unorthodox racing says to use, is a bit long. Will have to get a shorter one.

I say get one if you can, not a bad mod for $60 for used pulley + $40 for the belts. Took about a hour 1/2 to grind and install.

Have to see how it goes in the long run.

Now get a bored throtle body!

Steeb · Post by **Steeb** » September 7th, 2007, 7:00 pm

there is not much to be gained in terms of power however like installing a lightened flywheel, lighter rods and lighter pistons as well as lighter valvetrain.

the response of the engine is greatly improved. the engine can get to higher rpms sooner where it makes more power. this means u get to your power band quicker which makes a huge difference. even disconnecting the belt that drives the power steering pump pulley makes a big difference.

the ebay pulleys as well as the ur pulley both have the timing plate screwed to the pulley. if there is any issues with using one, i am most certain that they would both have the same issues. to avoid any problems that may occur, i would just suggest simply putting some loctite on the screws holding in the timing plate.