ANYBODY dyno a stock 05 auto
and then put on ur pulley
any gains
need see some dyno prove..

 

Sorry Jack, when I had my 94 Z28, there weren't many dynos around in this country so I couldn't put my Z28 on a dyno to test for every mod. I do however have friends in the KC F-Body club that have UDPs on their L98-LS1 F-Bodies. The consenus is waste of money.

I did however dyno a lot with my Maxima which has a .5 smaller version of the very engine we have in our G35's. The end result was no gain with the 4+lb lighter 20% UR UDP. My track results over the span of probably 60 passes on what was probably 8-10 day track days showed the SAME EXACT THING. No change.

Now I want you to tell me why a VQ35 is going to act any differently than a VQ30 when it comes to the UDP? Please enlighten me as to why basically the same rotating assembly is magically going to make gains. I also want you to show me the G35 dynos and 1/4 mile times that support these claims you and others are making.

Cute. After watching your road race video, I can see I'm not the only that has to deal with your pompus and F-you attitude.

 

And I had dyno proof on my 1990 300ZXTT of 9 HP and 12 ft-lb gains from installing an underdrive pulley. Caveat: at the time, I had already done other mods, including intake, exhaust, boost controller. A stock VG30DETT probably would not have gained quite as much. However, there is no doubt that the underdrive pulley would make a difference on a stock VG30DETT.

Oh, and when I sold my Z, it had 175k on the original engine and turbos, and still ran very strong, at 15 psi of boost (stock is about 9 psi)

Obviously that UDP really tore up the engine...

Dave

 

If the car doesnt gain more HP from the pulley but it winds up faster it sounds like a good mod? If it increases acceleration I would think thats a benefit lol

 

A pulley would show gains if you dynoed before and after in 1st gear...it'd show less if you dynoed in 2nd....even less in 3rd...by the time you get to 5th you're accelerating the mass (and accesories due to the underdrive) so much slower that its not going to show up much. Its about inertia. 1st gear has to accelerate the engine from idle to redline in the shortest period of time, so mass resistant to change in motion is going to have the greatest affect there.

The same is said for a lightened flywheel. In my LS1 camaro when I put in a light flywheel 1st gear was impossible....felt like I'd gained 50rwhp, the tires would light up in smoke half way through the rev range. In 2nd it was a lot less dramatic, and 3rd and up felt the same to me. On the dyno, it was 2-3rwhp difference. I also put a pulley on that car and first felt a better, all the other gears felt the same. No change on the dyno.

 

cant lose for 180 bucks. I'd go with KJR since it doesnt underdrive

 

Excellent post. There is a diminished return in power as the gears go higher and the most realized gain comes in 1st. It's all physics. However, since the car spends so little time in 1st, especially if you launch correctly and come off the line above 3000rpms, the minimal gains really can't be realized (you're talking hundredths of a second). The other thing to consider is that there is less rotational inertia therefore the tendency for bog increases which can potentially write off any gains from the pulley and with some drivers, they may be slower.

 

Just thought I post that its obvious the pulley does work on the G35 and here is the proof.

http://forums.freshalloy.com/ubbthre...b=5&o=&fpart=1

 

Wow, one dyno out of about 20 on this site and my350Z that shows some type of gain. That's a good record

Here's a recent dyno and "proof" of a UDP NOT working on the VQ35:

https://g35driver.com/forums/reviews/75567-dyno-d-kjr-performance-lightweight-pulley.html


Have you ever had a pulley on VQ? Ever tested it at the track? Ever dynoed it? I have. Zilch gains on the dyno and on the track.

Don't believe the hype.

 

Hmmm . . . I have been following you folks here. I guess the jury is still out for me then.

 

Hmmm... 1 out of 20? Glad I was that 1 then.

So before you spend too much time discrediting my run I would like to note that I have the Unorthodox Racing underdrive pulley; the "proof" comparison thread you noted uses the KJR lightweight pulley and they are two different units as the KJR is not an underdrive pulley. While my car and G35StrongMan's have similar supporting mods, we are on different dyno's and comparing different pulleys.

KJR should not show a gain on they dyno because it is OE sized, and is only a reduction in inertial mass. I would expect the engine to rev more freely and to have more responsiveness, but not increase power because it is not inducing underdrive like the UR pulley.

I have it, am happy with it and would recommend it. Thats good enough for me. Take it for what its worth.

 

6-8 hp is about what I figured, for a underdrive and lightened pulley. Not one or the other, but both.

Now, the debate cane go on and on as to whether it is harmful to your engine; I will not get involved in that debate. DaveB, you may be right on that, you may not. I don't know, and don't want to argue about it.

What I would like to know, DaveB, is why you think an underdrive and lightened pulley would not produce any gains?

Dave

 

There is more proof of it working than not sir.

What hype? Your hype with no factual data backing your bs?

Get over it Dave. Everyone I know who has installed a UDP has seen gains on the dyno and the track on many cars.

 

Good info helldorgado. DaveB likes stabbing people for mods he thinks do not gain because its his opinion but he never has the correct facts backing his statements up. I think everyone around here is starting to get tired of him.

Dave, because you got proven wrong again, doesn't mean its the end of the world.

Ah yea, my 10 sec argue limit is passed for DaveB.

 

I just read this thread and the evidence that they pulleys work far outweighs the evidence that it does'nt. I just put this on my "to get" list. One question whats the difference between the UR Ultra S Underdrive Crank Pulley, and the UR Ultra SS Crank Pulley Set? Thanks