rexi

Obviously not all pulleys are created the same.Most of the people on this site that have either unorthodox or agency power pulleys seem happy with them. HOWEVER, for some reason, some people who have the SR pulleys dont seem quite as convinced???????.

Just my thoughts. Maybe time to try a different brand before completely passing them off as worthless.

Regards
Rexi

Fanman

You're not going to get a huge amount of difference between pully sets, unless you drastically underdrive them, in which case you will kill your alternator, or AC. This isn't a Mustang GT, where you have a 20 lb. harmonic balancer, and you can take off 5-6 lbs. You are talking about the stock pullies weighing a few lbs. at best. You aren't going to have one set that is 3 lbs., and the other one 8 lbs. I do like seeing people's experiences with their pullies & seat of pants perspectives, but would like to see several people dynoing out their cars and showing good proof of real gains. When Whenson posted his gains in the other thread it was a lot more believable, but then all of a sudden the same/similar dyno shows up, but with 8X the hp gain...OK. If you believe in the product, and want to get then knock yourself out. Just don't get too mad when somebody posts a contrarian view to the matter & shows some evidence to the contrary. Again, let's see some more dynoes (not from the vendors, but real RX8 owners that have no financial interests in the product). That would be great.

toxin440

see the arguing posts for things like these pullies confuses semi-n00bs like myself. I read a few threads about people raving abou them, then see threads about people saying they are useless.

I'm slowly in the process of saving up some money for mods (almost everything except going FI) and pullies were originally on my list, but now I don't know what to think. For about 150 bucks... thats not bad but just gotta keep in mind thats 150 bucks that COULD be going towards my RP Supercat, or RB exaust.

r0tor

iTrader: (1)

this forum is full of reviews of products with results being reported that are more placebo effect then anything... take every review with a grain of salt

Nemesis8

iTrader: (3)

Only one pulley? The Unorthodox replaces all three.

yiksing

Underdrive pulleys helps your water pump to keep a constant flow especially at extensive high rpm use. Some also keeps your alternator life longer.

swoope

iTrader: (5)

so the aftermarket knows better than mazda on part life????

yes if you have a car that just does track time underdrive make sense.....

but if you drive you car on the street, not so much.....


beers

Beodude123

If you only have lightened pulleys, with the stock being so light, you won't notice a lot of difference. But when you throw underdriving into the mix... It can change quite a bit.

whenson417

Sorry for the delay, I have been out of the loop and just happen to notice a lot of concern about the dyno chart that Vivid Racing has posted. Just to let everyone know, they did not doctor or change that dyno chart in any way. It is just the same now as it was on the day I sent it to them.
Unfortunately, when I took my car to the dyno, the first chart they handed me was different than the first one emailed to me. I called Dynolab and had Arthur email the correct one and passed both along to Agency Power. For some reason (marketing reasons more likely) they chose to post the chart with the maximum hp gains, not the one that shows the gains throughout the rpm range. The chart they posted does appear to have some funky vibe about it because of the dips not matching up. The only thing I can think that could cause this is Dynolab may have had one run saved on a hp vs. rmp setting and the other on a hp vs. speed setting so the may not have lined up once placed on the same graph.
My thoughts on the pulleys, you would have to shoot me before I will take these off of my car. I do not believe these things create much or any power but what I do believe they do is allow my engine run at maximum power under any condition. I notice that when my car had old plugs, it produced more hp and tq in the lower rpm range, more so than when I put in new plugs. I dyno'd after I replaced the plugs and saw that my car made considerably less power in lower rpm's but there were extra ponys in upper rpm range.
About a month later I replaced my coils because they were burned out and noticed more power so I did another dyno to see where I was sitting. For some reason the first run was the best I had during that session so that is the chart I took home. I then installed the pulley about a week later and noticed the extra power in the lower rpm range. I took my car to the dyno again to see what was there. Not a whole lot extra in the top end (1-3hp) but there was about 10 or so gained in the lower range which makes me believe the pulley allows the car to run at maximum hp all through out the rpm range. Its like the pulley is giving me the best of both worlds, more hp in the lower and upper rpm range.
It all just could be a fluke and believe me when I say that my dyno's have some discrepencies like not being performed on the same day, same tank of gas, back to back to back. But hey, my car is my daily driver with just over 40k on the odometer and I do not work in a shop or have any affiliation with Vivid Racing or Agency Power. I just offered them my dyno chart because I was hoping to help out other potential buyers who want to know if they are buying a piece of crap or not. Hell if someone offered to give me a turbonater, I would test it on the dyno and if it posted gains then I would send them a copy of my chart as well. I just like trying to help everyone out.

oh yeah, here are all my dyno charts, i may have more posted in the dyno chart thread. I would explain which one is which but Atlanta Bread Company is closing and I do not have internet access at my house so I have to cut it short. Feel free to PM me if you have any questions.
Best regards.

staticlag

Small rev video while at stop light:

murix

Having had underdrive pullies on other cars personally and knowing that they had a positive effect on RX-7's (1st gen), I say they DO make a difference, BUT not so much on this car. Mazda has done a much better job of keeping things light than people give them credit for. 2lbs stock pullies is light! Every part is relatively light for what it is. The stock pullies are much lighter than on most cars. The stock pullies on my Eclipse weighed 8lbs! So is the driveshaft, flywheel, etc. I do have a lightweight flywheel and I like it, but any of these lightening parts is only going to make so much of a difference.

No offense to anyone, but the seat of the pants test usually is inaccurate and has a lot to do with self justification. If there was really that much power to be had just from swapping pullies, I am sure Mazda would have considered it.

Saying that, I still might get them. I like the overall effect of lightening as much as possible even more than it already is. Nothing wrong with that! It all adds up slowly and surely. That and I like mods.

murix

Oh yeah. Great write up! We need more of this stuff.

cooldriver88

Hmmm, so how badly will my subs be affected if I get this under drive pulley? I have two 10" Alpine type R's, and a v-12 amp, and I have a capacitor. I want to get the pulley but I don't want to have my system get all messed up.

HCTR154

I have SR motorsports pulleys and I can vouch that you will NOT pick up 12 horsepower by installing them. Regardless, when you are starting out well below 200 horsepower, every couple of ponies you can get here and there help.

Avalonstar

How hard was it to get everything back on?
(Excuse the stupid question.)