I assume the 4 pound pulley is the stock Fit pulley. I doesn't appear to have rubber dampening whatsoever, so a lighter pulley should only have benefits if the original pulley wasn't made to absorb any engine vibrations to start with. Am I correct in this assumption?

Darn it, I had my options backwards, the old posts were coming up first... way to start in a new forum

 

I'm still wanting one of these badly...

 

Found this at honda.com, so we should be safe installing these lightened pullies.

Noise, Vibration and Harshness (NVH)
The Fit is designed to provide a quiet and comfortable ride with minimal engine noise and minimal road noise intrusion into the cabin. To minimize the noise and vibration in the engine bay, Honda utilizes side-mounted hydraulic engine mounts (shown at right), a hydraulic transmission mounts (shown at left), a new crank pulley damper and a sound-absorbing composite engine cover. In concert, these technologies help to reduce the general noises from the drivetrain.

 

I'm not worried about safety! I'm more worried about HP gains/loss!!! THe T1R pulley Lost HP and this GTSpec/ Summit Pulley has no dyno charts that i can find!!!! RavSpec the vendor won't even answer me!

 

I have one from Summit and it's worth every penny. You feel the car responce a lot better.

 

I love my pulley to.
SummiT is the brand get. Its made from 7075 aluminum,
and not 6061 aluminum, which is heavier, and cheaper & possibly
unbalanced... available for the fit from at least 4 manufacturers.


6061 – Al-Mg-Si Alloys – Heat treatable alloys with good formability, weldability, machinability, and corrosion resistance. Medium strength, although not as strong as most 2024 and 7075 alloys. Alloy 6061 is the most common of these alloys and is considered to be the workhorse of the forging industry.

7075 – Al-Zn Alloys – Heat treatable alloys with moderate to very high strength, limited corrosion resistance, and very poor weldability. Higher strength 7075 alloys exhibit reduced resistance to stress corrosion cracking. 7075 alloys are widely used in aerospace and other high strength-to-weight applications.

 

Well All i can say is, either you jimmy or me have to do this dyno thing to seal the deal, are we gaining HP or losing!! Wanna chip in on me getting this pulley dyno'd? I'm trying to get RavSpec the vendor of GTspec here on the east coast who is selling the Summit pulley on US soil.

 

Are you sure gtspec pulley is from summit and not a replica? I have
seen 3 other brands that look identical to the summit pulley.

 

No it is the summit pulley, That is the company in taiwan that is producing the pulley's for GTSPEC, when i asked some china website that i found the p/n that you posted here, it led me to one china website. I wrote them an e-mail about a groupbuy on FitFreak.net. Then they wrote summit about the p[ulleys, and then they got in contact with GTspec the US distributor of it's pulley product, and that is when Mark from GTspec contacted me and said, "If you want to do a GB then you have to go through a vendor of GTspec the company who's bringing the summit pulley to the US. GTspec's own internet store is called RavSpec"

Besides hear'say, as you can see they look and weigh identical! Just no inscription of a company name on mines, b/c it was a test to see if it fit's the US L15a1 Engine!

 

Guys I'm amazed fitting parts to the car without running some dynos to verify! Anyway since this car is already dynoed (Honda Jazz) over here I'll attach the link OK! they even did 0-100 runs! and you can see the difference of using Auto CVT vs Manual CVT Shifting! Cool man!

Latest Info Page:
http://www.mythelogy.com/images/Dyno...eyDyno_Pg1.jpg
http://www.mythelogy.com/images/Dyno...eyDyno_Pg2.jpg

 

Guys I've been studying the graphs and gains per rev. Its impressive notherless cause you must remember its a NA we are talking about and with VTEC which is already quick zoomable. The OEM pulley weighted at 2.2kg which is hell of a heavy and the power loss is regained after reducing it to less than 800grams.

I calculated the HP & TQ recovered across the rev range as this:

RPM - HP - TQ
3000 - 6.4 - 14.9
3500 - 2.3 - 4.9
4000 - 3.8 - 7.1
4500 - 4.5 - 6.6
5000 - 5.6 - 7.6
5500 - 4.4 - 2.7
6000 - 1.8 - 2.3

to get average of 6HP and 14TQ at 3000RPM is impressive cause this will make the car more driveable especially in town. I've never bothered much about high end gains that ppl always wants cause cars like Jazz are basically town cars and regaining the loss power back at the proper Revs is what really matters.

Anyone that wants super power should go the way of putting in Turbos just like engine swap thing. But not many of us common ppl want to do that. Just want to have a more driveable car with less FC...hehehe

 

Mark from RavSpec says that he is willing to have the pulley dynoed!! I'll keep you posted!

 

Its made from 7075 aluminum,
and not 6061 aluminum, which is heavier, and cheaper & possibly
unbalanced...



errr.... its the other way round.
T7 is very heavy in billet form and hardness is higher.
T6 is lighter in billet form and medium hardness. (can be hard anodized treated) Why you are feeling that T7 is lighter is they cut more holes into it and make it thinner to compensate for the material weight.

The crank vibrations are higher on a T7 and a T6 cause of the hardness. If you take a screw driver and hang the T7 on the center hole with one finger and knock the screw driver to the edge you will hear the "thiiiiiiiiiiiiiiiiiiiiiiiig" sound if you do the same with T6 it's like "thiiiiiiiiiiiiig" about 1/2 T7 resonance. and if you take the Original Metal Pulley and knock its "thung" short and low bass.

Now the best part, sorry to say this the "thiiiiiiiiiiiiiiiiiiiiiiiig" thing will be what your crank is doing to the pulley every time 1 cylinder fires! and this sonic vibration will travel back and forth your crank cause its not dampened at the end where it should be. May cause earlier wear may not? who knows the answer? its been debated till death around the world!

Sometimes we tend to think harder bigger longer equates to better. Sometimes its right and sometimes its not so rite.
I still think its safer to have fun having sex with condoms than risking it. Unless your god dam sure its OK! Just an opinion.

 

Great dude, I hope you post it too so we can all share the info.... at least end of the day we know if this works or not unlike those air-leaking gadgets!