Underdrive Pulley

[SteveB]

Ebay pulley are super light and will make power but they're unbalanced

There's no machined balance marks on the expensive ones, either.

[DraZtiK]

why does everyone talk about power gaining off these? i don't see more than 1-2 whp outta this.. the biggest gain you'll see is more "free reving" which on the butt dyno it'll feel faster.. less mass to rotate would make your car rev a little faster, getting to the power band a lot quicker. i'd say its totally worth it.. maybe not the power steering or alternator one but the underdrive, yes. its like a lightened flywheel.. and the lightened flywheel revs up a lot quicker! just think if you had both! underdrive pullies aren't about power, same with a flywheel.

[deevergote]

True. They don't "add" power... but the amount of power it takes to spin the stock pulley is greater than the amount it takes to spin the smaller, lighter ones. Rotational mass, in comparison to stationary mass, is considerably heavier. As the diameter of the spinning object increases, the amount of power needed to spin it also increases. Smaller and lighter allows for more power to the ground. In that way, it is the same as a lightweight flywheel... as well as lightweight racing wheels and tires (Even lightweight 17" wheels are worse than stock 15").

A complete UR pulley set on an RX-8 showed considerable power gains. I've never seen a dyno chart showing gains for the F22 or H22, but I would assume it's more than 2... 5-6 most likely.

Still it does certainly feel revvier, like a lightweight flywheel. I have a lightweight flywheel as well (got it after the pulley) and it really does rev quickly!



Also, SteveB, why would there be a need for machined balance marks on the more expensive pulleys? I would assume a company such as Unorthodox Racing would balance the pulley before finishing it. To get a pulley with marks on it would look like shoddy work. Unorthodox Racing is a large and respected company, with the pullies being their main product.

A cheaper company that sells for a fraction of the price can't possibly be as trustworthy. If they sold such a large amount of pullies that they could offset the price by such a large amount based on volume I would possibly understand... but how many F22 underdrive pullies do you really think they sell? They plop them out of a machine for $10 each or less, and they sell them to idiots that probably wouldn't even know how to trace their motor failure back to the pulley in the event of such failure. Not to mention that anyone who would put such a cheap product on their motor probably has a number of other similarly low quality parts as well.

[trah]

you shouldn't change the undrive pully since its a harmonic balancer. the f22a1 is not internally balance like some vehicals but you'll get more vibrations then before i had the Unorthodox underdrive pulley and the AEM pullys didn't do shit just made me run my less battery power at low idle. wouldn't get them if i were you.i used my underpully for about a week when i took it off for an timing belt change it was a butch to pull out. and that it was all eating up by my plastic guard. well btw i have aem pullys for sale 100 bucks firm used them for a week and took them off. underdrive pully i threw away. pullys are for geezers who want to squeeze the most out of your engine. you will only get about 1-3 hp most of Unorthodox complete set. 1-3 hp for 300 bucks hmmm . i rather use 300 for a new motor like a f22b dohc and use your old tranny off the f22 well up to you guys on what ya want gonerz

[92BLACKEX]

Yea mine wobels and I dont think im gonna keep that one on after reading this, and I went through 2 of them and they all wobel so I think im gonna put the stock one back on.

[SteveB]

Also, SteveB, why would there be a need for machined balance marks on the more expensive pulleys? I would assume a company such as Unorthodox Racing would balance the pulley before finishing it. To get a pulley with marks on it would look like shoddy work. Unorthodox Racing is a large and respected company, with the pullies being their main product.

OK, I'll bite.
How?

You either add or subtract material to balance an object...ever had a flywheel balanced? Or heck, look at the stock pulley. It has a balancing mark, straight from Honda, another large and respected company. An anodized finish isn't going to cover it up.

I think the alloy pulleys are just too small a diameter and too light to have enough out-of-balance to worry about.

[deevergote]

Even a small variation on a rotating part can be important.

As for there being marks on the stock pulley, and not the aftermarket piece... I would think that an aftermarket company would strive to make thier parts look attractive. When you get your new honda, you don't give a damn about what the pulley looks like. They don't have to be pretty. But when you get JUST that pulley in the mail, it had better look good enough to eat! If the UR pullies looked plain like the stock pullies, I would think they would sell less. People are impressed by pretty things. That's why clutches, flywheels, and pressure plates... things you never see again after you put things back together... look so pretty.

Do you have a picture of the Honda balancing marks? I'm not sure I know what you mean. The only marks I'm aware of are the timing marks... which the UR pullies do have.



trah... I can barely understand what you wrote. However, how do you say pullies are for geezers that want 1-3 horsepower? What about an intake? Or a cheap header? Do you think you get astronomical gains from those? You're looking at about 5hp each, if that... When it comes to bolt-on parts, you can only get so much. After I/H/E are done, you have 3 basic options for any proven power... tuning, cams (and cam gears, which go hand in hand with tuning), and pullies. After that, you're looking at forced induction or major internal work on your motor.

[trah]

so yes it is proven on i/h/e that you get gains, but in my opinion all that you that you get for spending about 600 - 1000 bucks, depending on what you get you would have an increase of about 5-10 hp at most. when you really sit down and think about how physics and gravity works you'll get it. For instance you got a cold air intake bigger pipe and whatnot you'll have more air trying to get in right... for that matter you'll get restriction right when it goes through the throttle body since your throttle is not made for that. air will flow back up towards input and get forced back down like a pouring water in a tube that would not fit directly it will spill. thus causing your intake mani and head take more abuse since it building more and more pressure within internally. the restricton of the intake is where you get your sound of air pushing back upwards of the downward flow of the intake. I had a header (DC) and a Ijen cold air system and I will tell you honestly on my 99 honda civic ex (d16y8 w 7.5 fidanza fly) and i ran my friend with the 2000 accord v6. when i was stock with (i/h/e) i took him on the highway and lost in the quarter. once i put in the i/h/e. (injen,DC,greddy) i lost on the highway. to get real gains in horsepower and torque you really need to build internally that were all the power comes from. anyways why would people say i get 20 hp from my intake 30 from my exhaust thats BS. I dynoed and everything never used piggy back like uber and stuff until i got my cb7 hahahaha. but really come on now people what do you really expect to get at least 10hp on i/h/e you would need to spend at least 1k (brand new) Injen cold air system, DC header, greddy exhaust (since how they pipe it flows better) If you dislike what i say well its my opinion as stated above.... and back to pullies whay would you want your car to when idles lose battery power just to get .5 - 1 hp? when i can damage your electrical system. thats why AEM does not make a underdrive pully since the factory is a balance. UR is a waste of money go buy a new valves and redline it to 9rpms. thats better then wasteing it on something you won't feel in the car.

[AccordWarrior]

If you read up @ UR's site, you'll find that underdriving only accounts for ~15% of the power gain.
Most is from the almost four pounds you lose off the crank assembly.

Pretty sure the oil system scare is *one* oil pump that went blooey, and the story has been repeated ad infinitum on every Honda board out there, making it sounds like "lots" of spoiled oil pumps.

I think in addition to that, a lot of people in the Civic world were using CTR pulleys (lightweight) on their B16's and blowing stuff up.

They make pulleys with harmonic balancers, you just have to pay for them. (Think $400-up)

[accrdpower]

.....so much wrong info from certain individuals it is scary.... accordwarrior has it right. and the person who said u get like 1-3 hp from pullies and 1-3 hp fromk a i/h/e......wowza. someone is misinformed. all in all, the most u can get outta a f22 with only bolt on's is around 170CRANK hp. there has been an engine dyno with a stock f22a6 block, head, stock tb, manifold and it had 176ish hp....or around that. that is crank hp btw. anyways, if u don't want to spend the money for hp then don't. but u have to pay to play. don;t expect things to be cheap and if they are real cheap i'd wry as to WHY they are cheap. i hope whatever u choose is based on facts not opinions best of luck

[deevergote]

so yes it is proven on i/h/e that you get gains, but in my opinion all that you that you get for spending about 600 - 1000 bucks, depending on what you get you would have an increase of about 5-10 hp at most. when you really sit down and think about how physics and gravity works you'll get it. For instance you got a cold air intake bigger pipe and whatnot you'll have more air trying to get in right... for that matter you'll get restriction right when it goes through the throttle body since your throttle is not made for that. air will flow back up towards input and get forced back down like a pouring water in a tube that would not fit directly it will spill. thus causing your intake mani and head take more abuse since it building more and more pressure within internally. the restricton of the intake is where you get your sound of air pushing back upwards of the downward flow of the intake. I had a header (DC) and a Ijen cold air system and I will tell you honestly on my 99 honda civic ex (d16y8 w 7.5 fidanza fly) and i ran my friend with the 2000 accord v6. when i was stock with (i/h/e) i took him on the highway and lost in the quarter. once i put in the i/h/e. (injen,DC,greddy) i lost on the highway. to get real gains in horsepower and torque you really need to build internally that were all the power comes from. anyways why would people say i get 20 hp from my intake 30 from my exhaust thats BS. I dynoed and everything never used piggy back like uber and stuff until i got my cb7 hahahaha. but really come on now people what do you really expect to get at least 10hp on i/h/e you would need to spend at least 1k (brand new) Injen cold air system, DC header, greddy exhaust (since how they pipe it flows better) If you dislike what i say well its my opinion as stated above.... and back to pullies whay would you want your car to when idles lose battery power just to get .5 - 1 hp? when i can damage your electrical system. thats why AEM does not make a underdrive pully since the factory is a balance. UR is a waste of money go buy a new valves and redline it to 9rpms. thats better then wasteing it on something you won't feel in the car.

Your opinion? You're stating hard numbers, and saying it's opinion? You don't pull horsepower numbers out of your ass, claim knowledge of physics is used in your guessing, and then call it opinion. Either you know what you're talking about or you don't. If you don't, then I would suggest not participating in the discussion. It's the uneducated argument that you and half the people who have replied to this thread present that has given worthwhile parts a bad reputation. There are a few worthwhile arguments presented here, and those are worth discussing. The rest is just regurgitated bullshit most likely stemming from some dumbass that a) got cheap parts, b) installed them incorrectly, or c) had something fail in his motor and ASSUMED it was the pulley's fault. I have yet to see hard evidence. My car is the most evidence I have so far, and it supports the claim that the pulley is not harmful... note that I say "supports". Even with my personal experience, I don't consider it "proven".

Yes, the throttle body is a bottleneck. You're right about that. However, the stock intake system is very restrictive. A cold air or short ram intake, even with the stock throttle body, will give some gains. A GOOD header (DC isn't really a very good piece) will definitely give gains (SMSP has been shown to give upwards of 15hp on an internally stock H22). A good exhaust will also give gains. The less restrictive you make the entire system, the more power you will make.

I've been running my UR pulley for almost exactly 2.5 years now. I've had absolutely no issues with charging (and my alternator is original). I am still running the stock alternator pulley.

If you want something you're going to feel on the car, you're looking at some real money. Either do it by getting one bolt-on at a time, or do it all at once and feel the difference. OR get a turbo kit or motor swap... that is the only way you're really going to feel it.

Still, if $300 is going to knock a few tenths of a second off my 1/4 mile time, it's worth it to me.



BTW, I paid $80 for my pulley.

[trah]

no i don't shit out horsepower. Its experience where else do you manage to get claims. even magazines are a load of shit just saying that to make money. need to find my dyno sheet for my civic when i had i/h/e and i'll show you hard cold facts on what i/h/e really do. even though 160 hp to the crank you loose 15% to the wheels and then if your tires are sh!tty (1-2%) your not making nothing. ok no more opinions here is FACT while i was driving in my 93 civic (DC5 interior conversion) (UR undercrank pulley, AEM pulleys, d15 block d16 vtec head, d16 tranny, injen intake, dc header, greedy 2.5 exhaust) driving about say 1k miles after i installed the pully and yes after i installed it lock tite on the pully bolt. driving down the road crank fell off. had to tow it back to the house looked at it and the bolt broke with the crank pulley. pully was cracked from the key portion. thats fact. i was making 123 to the wheels when i dynoed and without the i/h/e i was making about 114 to the wheels. i'll get my dyno up once i find it and prove to you how much it really does. yes i agree with you on how loosen up restrictions you'll get gains but not signifigant gains.


ahh i give up since this will start an all out war with tuners on the forums.

[deevergote]

I still have yet to see a relevant argument.

I don't mean to argue in an angry fashion, but you're speaking as if you have solid proof... and then claiming it to be opinion. "Opinion" would be "that's fast". When you start throwing numbers around, you get into a whole different realm of argument.

Your expeience is from a Civic. A much smaller engine than the F22 or H22. Your exhaust was WAY too big (2.5" is too big even for the F22 unless it's turbo or heavily modified NA). The DC header is a solid piece, but it's nothing fantastic. It's a better-built budget item, made for mild gains and emissions compliance. Furthermore, with those mods, you were probably running extremely rich. If you tuned your ECU properly, you would probably have unlocked a good 10-15hp, if not more.

15%-18% drivetrain loss is always assumed. Tires have nothing to do with power production. Shitty tires will keep you from putting the power to the ground, but you will still be making that power. If your tires are so bad that you break loose on the dyno, they should never have seen the streets anyway!

As for your pulley install... what did you torque it to? Loctite won't hold on an improperly torqued bolt. If the bolt broke, you probably overtorqued it. As I said before, people who claim the pulley to be a problem are probably blaming some other flaw on it... I've never heard of a pulley breaking the bolt. That's more absurd than the crank pulley blowing the oil pump (which runs on a seperate pulley... BEFORE the crank pulley comes into play.)


I'm not fighting with you. I'd just like to see some good evidence. It seems to be the popular belief that underdrive crank pullies are dangerous. However, I've NEVER seen a good argument yet supporting that claim. It's sad to see dozens of people regurgitating information that they picked up from an uneducated source. It's because of people like that that caused me to pay $1750 for an engine swap because "it's too hard for you to do yourself!" was the common reply. Guess what? NONE of those people even had swaps. It was all hearsay. And it was false. From there on out, I realized a simple statement is never enough... give me reasons. Make them good.

[trah]

im not here to fight either... how many miles you have on ur accord since you had the pulley in? from when you put the pulley on 2 and a half years ago roughly 40k? have you checked your bearings lately and hmmmmmmm brb going to buy something to eat

[deevergote]

30-40k, yeah... I could probably dig up the work order to get an exact count (I had a shop do the pulley).

I haven't checked the bearings, but for 100k on the motor, it still runs smoothly, and accelerates flawlessly to 7500. No knock, no compression loss. The only thing it needs is a valve adjustment, and that certainly isn't relate to the pulley!