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I have about 10,000 miles on my car and i am looking for that good first mod. I am thinking about an exhaust but do not want loudness. something a little over stock but nothing that is going to make lay people question if my car is ok. I do not know if it is worth going for the whole turbo back....i guess that is why i am looking for some ideas and help. i am just really scard that i am going to spent alot of money and not like what i get because it is too loud.

Also looking for some other good ideas for my first mod.....
 

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yup i agree with god
 

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Try the Vishnu Pulley, Berto and I installed it yesterday and the car feels noticeably lighter. I'm not sure how much the pulley itself is because I got the full stage 0 kit but it should be under $200 by itself.
 

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what gains?

What kind of gains can you expect from adding an uppipe and setting a boost cont to 15psi?
 

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Discussion Starter · #8 ·
What harm can you do with setting the boost to 15psi...i know there must be some negative to doing so..
 

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boost at 15 is fine.. With an up-pipe you get a better exhuast flow just like any part on an exhuast, it eleminates the cat. converter BEFORE the turbo. Its worth the 200 bucks.
 

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BlazinWRX1 said:
Try the Vishnu Pulley, Berto and I installed it yesterday and the car feels noticeably lighter. I'm not sure how much the pulley itself is because I got the full stage 0 kit but it should be under $200 by itself.
What do pulleys do for a turbo? I understand gains for a supercharger b/c its belt driven but a turbo isnt run off a belt. Is it really worth it? I know it will put extra strain on the already undersized 70A alternator.
 

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Generally speaking...

You'll see gains with an underdrive pulley regardless of it being forced induction or naturally aspirated. Turbo or supercharged.

I think what you're referring to is a different s/c blower pulley, which is not the same as what Blazin is talking about. That pulley is replaced to make the blower pump more boost.

Most applications you see for underdrive pulleys are for the crankshaft. Underdrive crank pulleys give you two things: lighter than the stock pulley, smaller diameter (15% - 35% or thereabout). The smaller diameter lighter pulley removes some of the parasitic drivetrain loss and also makes the engine a little more rev-happy. In power terms you gain hp. The more displacement you have, usually the more power you get from this. Vishnu pulley for WRX is said to add 7hp. Also, I've not read of any problems with the cars electrical system after underdrive pulley installation.

The Vishnu Stage 0 costs under $1k and seems to have great inital mods (uppipe, pulley, manual boost controller, plugs, unichip). I plan to order mine soon. 265hp from this sounds nice. Great to build on from there.
 

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I believe Vishnu's quotes on the pulley. I got between 3-6 whp on Hondas with an Unorthodox Racing pulley. They also make one for the WRX which I'll probably pick up one of these days and throw on. It's not a mod you can feel though. The power gain is very linear and is difficult to feel seat of the pants but it is there on the dyno.
 

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Yup, I had a 3 piece set of UR pulleys on my prelude and I loved it. BUT, there's quite a bit of debate about damage that can be caused for a car that is run w/o a harmonic dampener. Do some research and make your own judgement call.
 

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All8up said:
Yup, I had a 3 piece set of UR pulleys on my prelude and I loved it. BUT, there's quite a bit of debate about damage that can be caused for a car that is run w/o a harmonic dampener. Do some research and make your own judgement call.
I think that is good old fashioned i-club paranoia. In fact, it was Vishnu himself that created a lot of that paranoia (before he released his own crank pulley of course). :rolleyes:
 

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God said:


I think that is good old fashioned i-club paranoia. In fact, it was Vishnu himself that created a lot of that paranoia (before he released his own crank pulley of course). :rolleyes:
... after two years of watching, waiting, testing and investigating. I don't see what's wrong with that.

As for gains, we've documented 10-11 wheel hp gains (on a dynojet) with the pulley alone. With no discernible loss in lighting or AC effectiveness. After testing various diameters and weights, I think the final product is about as good as it can be as far as performance goes. And the gains are indeed perceptable to even the most casual drivers.

Cheers,
shiv
vishnuperformance.com
 

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I agree Vishnu. I'm sure the pulley works great! I've always had great luck with underdrive pulleys on Toyotas and Hondas. My beef is with all the paranoia on i-club about it being bad and my question to you is why were you advising against it before you had finished your research.
 

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God said:
I agree Vishnu. I'm sure the pulley works great! I've always had great luck with underdrive pulleys on Toyotas and Hondas. My beef is with all the paranoia on i-club about it being bad and my question to you is why were you advising against it before you had finished your research.
First of all, not all of the paranoida surrounding underdrive pulleys is unfounded. In certain applications, they can indeed be troublesome. And I have seen this be the case in Miatas and BMWs. This being the case, it would be irresponsible of me to offer (or recommend) them until I conducted sufficient testing, both on the street and on the track (with the USTCC race car). Once satisifed, the next part of the testing was to figure out optimal diameter for the pulley.

And contrary to popular belief, the whole "lightweight" aspect to underdrive pulleys is utter nonsense. Nearly all the gains provided by an UD pulley is through underdriving effects-- not from a reduction in rotational weight. This is easily quantifiable on an intertial dyno. It also makes sense when you look at the raw numbers and consider real physics. So the challenge is to find out the speeds at which individual accessories like to run at (minimal parasitic losses) while still doing their work. Too slow and everything suffers. Weight is not even a consideration.

My 2c,
shiv
 

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"UNDERDRIVE" is a definition in itself. It "underdrives" your accessories that is run by associated pulleys. To a certain point that is... e.g. your alternator. The max voltage/amps would be reached at 2000 RPMs. Where as if one had a UD pulley, it may take 2500-3000 RPMS for maximum charging. This mod would not be recommended for people with high amp stereos.
 

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Shiv said:
... contrary to popular belief, the whole "lightweight" aspect to underdrive pulleys is utter nonsense. Nearly all the gains provided by an UD pulley is through underdriving effects-- not from a reduction in rotational weight ...
So if you made the pulley 20lbs heavier it wouldn't hurt anything? There has to be some logic behind the weight.

From my experience also... what about this example. 40 lb wheels vs 20 lb wheels. Same diameter. Running which set will make your car fastest?

Not trying to argue, but just getting ideas out in the open.
 
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