double post

Yeah, that could be so. My buddy had different results though.

Its not uncommon to get a little bit of power out of the pullies, any time you lower the weight of a spinning mass, it requires less to spin it. Plus they look pretty.

hey if anyone is interested in some blue greddy pullies, i have some that i might be willing to get rid of (since i already have some). i got them with my greddy turbo kit, i belive i have the belt that comes with them too. PM me if interested, since i havent advertised them.
Adam

theres been a reoccuring question that no ones bothered to answer...Do you need to remove the airpump for all/most/some of these pulley sets?

Also, whats the difference between the pettit, ebay, unorthodox and a greddy set?

pettits looks like it comes with 4 pulleys and 2 belts, greddys looks like 2 pulleys and one belt, idk what the unorthodox one is

i guess i will answer the ebay ones.

two pullies and one belt

the wp looks like squeeze cast aluminum (too large to mill) and the alt looks billited.

They are both larger than stock.

The only concer with running smog pump is a new unique belt length must be purchased and the space between the wp housing and the wp is small.

It is larger enough to pass a belt over though as i have tried.

i would say it's pump friendly but most ppl prolly never try since that's one reason to get the greddy or the ebay kit.

Re: lightened pulleys
 

If you get the pettit pulley you don't have to take the center bolt out. Just the four bolts on the outside. You can not damage anything.... the $299 price tag is outrageous I'm glad I didn't buy mine

http://www.pettitracing.com/Frameset.html

i didnt notice any gains with my pulleys, but hey call me ricer. i did it cuz it looks good.

As long as these sets do not drastically change the engine working dynamics to fall below stock standards, then I guess the set(s) aren't a bad deal after all! Even if the H-P gains are minimal, it's not a bad price.

Re: Re: Explain how/why aluminum 2-piece pulley set can add 15-22 ponies??
 

Copy That!!

i though it was a great deal and was actually surprised by the quality.

i don't want to just pay for a name.

even if there was no hp gains i think it would still be worth it for your peace of mind.

Do you remember the name of the "Seller" you got them from?? Thanks.

.

I talked to my buddy, 15 rwhp. The dyno pulls were on the same day, same dyno no other changes. ;) 360 rwhp car though, not stock.

tsai1996

Re: Re: Explain how/why aluminum 2-piece pulley set can add 15-22 ponies??
 

The first initial results that Unorthodox put on their website about 7 years ago came from my car. We did before and after dyno tests of their main pulley and the difference was around 12-15 RWHP. Dont yell at me I did not do the dynoing :)

Jason

Re: Re: Re: Explain how/why aluminum 2-piece pulley set can add 15-22 ponies??
 

Sweet, there's one data point that actually isolates the difference. Still, 25hp was an exaggeration :)

Dave

If you can not reproduce a considerable measurable difference on all cars that you make this upgrade then the claim is BS.
Sorry, one car does makes the rule and besides we don't know the real facts.
Measurements done by the manufacturer are always questionable.
The measurements need to be performed by a neutral party.
Any one doing the pulleys should be able to reproduce to some extent their claims.
*Note to self, get the BIG bottles of N2O since it = more power than the small ones*
:D

So, how come nobody's bid on these yet??

Re: Re: Re: Explain how/why aluminum 2-piece pulley set can add 15-22 ponies??
 

Thanks Jason that was helpful. How much overall horsepower were you pulling on those runs?

Reason I ask is that I'm wondering if overall gains aren't a percentage of overall horsepower - like when you add an air filter and gain 20% more air flow which translates to different overall horsepower gains depending on mods.

If it was me, I wouldn't risk getting an important part such as the main pulley from some ebay shop. I've had issues with the quality of knock-off parts purchased from ebay.

I dont remember what the car way dynoing. I think it was around 270 RWHP.
The ebay pulleys are not going to free up much HP. Its the main pulley that you are going to see HP gains from. I know of some other cars that have done some before and after tests and did pickup some HP.

Jason

yeah don't expect alot of hp from just a wp/alt. Like jason said it's the main that free's up the most.

i just think it's funny when ppl atest to 10hp on a dyno for pullies or whatever and no one will believe them. It has to be temps outside....there wasn't heat soak like before.......but if you dyno a intake/dp/ic no questions asked.

ok why will hte main pully free up all the power? it just spins.... theres no drag on the main pully like the pullies that are attached to the accessories -heath

the main pully is the heaviest and reducing that one effects all the other pullies.

Quoted from Unorthodox website
"These gains are obtained in two ways. First, and most important, is the weight loss. There is an average of 2.7 HP gained from every pound lost off the crank shaft. With the lighter accessory pulleys, as much as 15% to 30% more power can be found. 85% of our gains are from weight loss.

The rest of the gains are from underdriving, which accounts for about 15% of the total gains. We do not push underdriving for two main reasons. Our main reason is to keep charging systems, air conditioning, power steering, and water pumps moving fast enough for every day driving. Second, not much horsepower is gained from extreme underdriving.

All of our underdriving is done with the crank pulley, not the accessory pulleys (most applications). This is done so maximum weight loss can be achieved at the crank where most of the horsepower gains are found. The accessory pulleys for most applications are stock diameter. Since our Ultra Accessory pulleys are the same diameter as the stock units, you may install an Ultra Street crank pulley as a first step. Then, at a later date, you may purchase our accessories and install them without having to change belts again (on most models)."

Jason

i was close when i said 1lb is about 2hp :)

i think SCC mentioned it too in one of their articles