interesting--thxs whenson417 I have been looking at that pulley. I thought it may be just as effective as the more expensive ones that include the alternator and water pump pulleys. Any gain is from the underdrive
olddragger

 

The thing is, as Rotary God and others state about dyno charts. Peak numbers do not show the whole story. Once I post the dyno chart you will see that in most of the areas I am receiving 6-10 whp and 10 ftlbs of torque all across the chart up until my 3rd set of ports open. Please keep in mind that other factors may play a roll as well like gas and dyno'ing on different days but the outside temps were fairly similar from what I can remember.

 

thanks-cant wait to see the chart
olddragger

 

thanks for bringing this up, I tried to get some response in the vendor's forum on thsi topic and went about it the wrong way. my main concern is heat and the charging system, if neither one of these things is compromised/negatively effected I will probably go for this as well.

 

mine is extremely responsive at part throttle and really zings the revs now with the SpeedSource pullies and A/C delete, but I made so many other changes including some substantial weight removal it's hard to say what's what

 

SR pullies installed for over 2 1/2 years... no overheating issues, but no noticeable performance added either.

 

This was the chart that Arthur from Dyno Lab emailed me, which is different than the one he printed out. The one I have printed is between my runs 13 & 12 which have the two peak hp numbers closer but a greater difference along the range. The one shown below has the hp throughout the range closer together but the peak numbers are further apart.
My take on it is, this pulley is allowing the engine to provide the best hp at all areas of the graph, except after the third port opening which is puzzling me. My car made more hp down low before I changed out my plugs and coils. I have the charts to prove that as well, since I had a dyno run after each change.
Please note that these results may not be typical as the gas was from different sources and there is a chance that the last dyno had summer blend gas while the previous one had winter blend.

 

looks like possible misfiring on the top end to me ..

 

Nice whenson 417 --looks like a true gain. interesting that the 1st"dip" is at a differant point. Whats up with that? Agree with team-probable some misfire in the upper range but it also coul be a pick up problem. We all know the plugs get bad for the upper ranges fast.
olddragger

 

To tell you the truth I do not know what is up with that graph. Like I said earlier, it is a different chart than the one printed out and handed to me which has the dips in the same place.

I hope it isn't a misfiring problem since I had the plugs installed early March and the coils replaced earlier this month.

 

maybe the knock sensor was being erroneous then

 

SR Motorsports here. I did a dyno a long time ago, and posted it here. Gains were about 1-2 hp across the rev range. The original post by whenson is about what mine did (188.9 to 190.6, although mine was from about 177 to 179)...though my mid range was pretty much about1-2 hp across the board. Looking back I would tell you to get a nice air intake or hi-flow cat for the same money, or even a nice used Canzoomer piggyback ECU.

 

I installed the SR motorsports pulleys a few weeks ago. I didn't notice that it "felt" any faster.

I'm positive the hp gains are small, probably 2-3 hp, and not the 10-12 most of the pulley makers claim. These rotary engines just don't respond to bolt on mods like my old Fox body Mustang. Regardless, my RX 8 is twice the car my old '94 Mustang GT was.

 

hi guys just my 2c worth for people that are considering buying the lightened pulleys / lightened flywheel when istalling either or both you car revs will rev quicker throughout the whole rev range but at a cost , the downside of installing these is that you will lose torque in my experience they are great if u are installing FI as torque will be picked up from turbo/blower

 

Ok guys, I finally got the dyno chart that was printed out and handed to me emailed to me. See how I said that if my car made more peak power then the power across the range suffered a little and vice versa. It seemed the pulley helped out all around.

 

5 % more torque ...

sames to be nice I think ... for 144 $

 

well, just ordered my Agency pulley from Mazdaparts. Hope I get the same results. Since the pulley comes WITH the belt you need and is over $100 less exprensive than the others offered--I said "why the heck not try it?"
olddragger

 

My SR Motorsports came with the belt, the kit wasn't that cheap though.

 

Ok i put the agency pulley on. cleared my expected cel and the car has relearned the idle etc. All i know is that on MY car i can definitely "feel" the differance. above 4K is obviously noticable. Feel it MUCH better than the revi intake with cai (just for reference). i know everyone hates butt dyno's but thats all i have. I have no interest in saying something is there when there isnt. it is the best under $200 mod i have done. heck it is the ONLY under $200 mod i have done! Took 30minutes to put on. Works well for me.
olddragger

 

SR Motorsport here. Definatley overpriced but worth it if you want to get a little more power out, (nothing to cosmic). Only thing is when its above 80 outside they squeak a little. I have had them adjusted (alternator moved a little, tightening) but they still have a sound. No belt slip though and solid all the way up through the rpm. Might be the brand of belt. I don't know anyone else had this problem?

 

i just added the sr motorsports wide grip pulleys and the difference is great. This pulley kit is sourced from their rx-7 parts list they just made it available to work w/ the rx-8 pulley set-up. It replaces the main crank, water pump, and alternator. The kit also includes one wide grip belt for the pulleys and one regular size belt to connect to the ac and a bilit acorn nut for the alternator. This kit rocks and is a far cry better than the origional kit put out by sr motorsports.

 

Did you install it yourself? Easy?