Gauging interest: Crankshaft Underdrive Pulleys

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I am considering designing a new part for the Mirage, an underdrive crankshaft pulley. I've designed one of these in the past for another car and did a group buy on it. The picture above is what was made. It went quite well and the buyers were very happy with the product. We still get inquiries for these every now and again and that was many years ago.


What is an underdrive crankshaft pulley?
An underdrive crankshaft pulley replaces your OEM crankshaft pulley. It is a little smaller in diameter and made of aluminum versus steel. This leads to reduction in weight. In the example above, the OEM pulley was 5.5 lbs and the underdrive crankshaft pulley was 1.2 lbs. It also spins your accessories a little slower.


Benefits of an underdrive pulley.
The reduced rotational weight increases throttle response. Spinning the accessories slower reduces their power consumption. This gives you more horsepower to the wheels, and also increases fuel economy (honestly probably not real noticeable). Its a pretty easy item to install. Most places that sell these claim about 1-2 hours.


Drawbacks of an underdrive pulley.
If an underdrive pulley is so great, why doesn't Mitsubishi put one on to begin with? Well, because it spins the accessories slower. This means you don't get quite as much power out of the alternator at low rpm. If you have a huge aftermarket stereo, this maybe isn't the best mod for you. It also means your A/C won't cool off quite as fast in summer. Most people can't notice the difference unless they're in a fairly extreme climate.

How much will it cost?
This is highly dependent on how many people are interested as with any group buy type deal. My best guess is it will be in the $100-175 range. The one you see above sold for $155 shipped within the US. We can ship international, you just have to pay for shipping.


If you're interested, please say so. I'll keep a list of interested people here in the first post.

Interested People:
1) Fit
2)

Interesting but not interested..

I am interested in this. I have a Works Engineering light weight pulley but it doesn't under drive which doesn't make much gains if any.

Great to hear Fit! You've been added to the list.

I am interested in a custom made underdrive pulley. If it will make any difference in increasing fuel economy, then yes!

I'm interested BUT I might be in what's called an extreme climate. People from AZ come to my state and complain about the heat/humidity. That air conditioner is important, but I'm thinking above idle the compressor cycles on and off anyway, which means it could spin slower and still work.

Ugh. What I really need is a lathe. Of course, if I got a lathe, I'd have to get a mill to keep it company. Then I'd want a hemsaw to cut stock. Then I'd want a forklift or crane to load the saw. Then once I had a saw, I'd have to start looking at a plasma for flat stuff. Then I'd want a brake to form what I cut on the laser. Might as well get a roll to keep the brake from getting lonely. Then I have all these machines, but only one of me, so I'd better hire an operator or two. Then I'm going to want a laser to do nice small flat stuff. It would never end. So I can't have a lathe.

Qrush is currently looking into having NST make up some pulleys for the car. His thread is here:

https://mirageforum.com/forum/showth...58-NST-pulleys