Will adding the pulleys require a change in tune? I wouldn't think so but it's always better to ask the question.

 

Nope.

 

+1 ^

 

Everyone says pullies. Is that plural? I only ever see one for purchase on any given website. What do you get from SLP or Steeda.....?

 

Thanks.

 

Had mine on for a month now, no charging issues, not cooling issues and .5-.6 better mileage, revs quicker and runs smoother

 

Next question is on the belt - does the tensioner take up the slack on the stock belt when you change pulleys? Also, if you go S/C down the road will the new belt work with either the stock pulleys or the UDP's?

Just trying to plan a little for future mods.....

Thanks.

 

yes it does take up the slack. and when you go S/C down the road, you can no longer use the UD pullies, you will have to put your stock pullies back on.

 

Thanks, that is good info to have. getting excited about reading about the Whipple S/C and just wanted to start gathering info if I go that route.

 

The alternator on the 'vic was probably not a large as the Mustang, as the stang has a lot more electronic stuff to run, not to mention a 1000 watt stereo option to run. Larger alternator means underdrives don't affect it as much.

 

I would say that 95% of the people use the Steeda UDP's. The Steeda set comes with a new crank pulley and water pump pulley.

 

How hard are UDP's to install? What all is involved? Is it soemthing I can do easily or will it require me taking the front end off to do it..(j/K) but seriously what do I need to do to change them out?

Thanks

Jeff

 

Besides basic hand tools, you only need a torque wrench and a set of pully pullers- I rented the pullers from Autozone. If you search, there are lots of install threads for pullies here on the site.

 

My steeda UDPs and Meziere water pump killed my battery which killed my $700 alternator. If you use this combo be proactive and get an optima yellow top battery

 

Dustin,
How did your pullies kill your battery? Provide proof please. If you pullies would not charge your stock battery they would not charge your Optima yellow. Right?? I think you had some other problem. I have run the same set up for 14 months and it was 8 degs. here this morning and she started right up.
Scott

 

had steedas for almost 2 yrs. 30k miles of nyc driving. no problems at all. they are a good mod.

 

Ok, How about Cross Country Driving? I travel for work and Drove from DE to NorCal. Would it affect that type of driving?

 

Thanks for the info. I'm getting them for Christmas. As soon as the holidays are over several guys in our car club are going to help me put them on. One guy has a garage with all the tools I'll need. I look forward to those extra 10 or so horses. Next is Kooks and a catted x-pipe.

 

Just some thoughts..

Generaly the electrical system design is such that the alternator can, at idle, satisfy all likely-concurrent loads: lights, a/c, stereo (at a subset of max output), ECU, etc.

Underdrive pulleys are a two-edged sword: spin the belt and/or driven devices slower (alt, compressor, etc) and you WILL experience:
-reduced accessory losses (a few more HP, especially at higher rpm)
-reduced accessory output

If you have a tune on the car, you can use the programmer to set the idle higher to compensate for some of the pulley reduction. This is a good idea since it will not give back any of the power gains at but will keep the battery better conditioned.

If you're lucky, running underdrive pulleys will just shorten battery life (can be considerably shorter -- from 6-8 years to 1-3 years DEPENDING ON YOUR DRIVING SITUATION.

If you have a Shaker 1000 and like it LOUD and BASSY, drive in stop and go traffic for much of your commute in pre-dawn hours in Phoenix, don't be surprised if your batter life is even shorter than 1-year.

If your daily driving is typically a freeway commute with little or no dead-stopidling, your battery life may not be affected much at all, even with heavy accessory use: a/c, lights, stereo...

Most people think of a battery kinda like a jug of water, you drain it down and the alternator fills it up, and as long as it doesn't run out (you get ahead of the alternator for too long a period) you're ok.

But that analogy is not entirely a good one. Battteries are generally only elastic in the top 10% of their capacity -- the deeper you dip beyond that starts to shorten their life by more and more (disproportionately). Once you get to the point where you're discharging up to 40% or so (depends on the quality and design of the battery), life span is greatly reduced, especially if it sits in the reduced state overnight (as opposed to being recharged before shut-off. However, DEEP cycling of even a quality automotive battery beyond its design-point even with a 'full' recharge will greatly reduce its life (a deep-cycled impaired battery will never reach full capacity again). Marine batteries are designed for deeper cycling but give up some other capabilities in the trade (marine batts are not recommeded for cars).

A severe service battery (e.g. optima yellow/red-top) will prevent spills and take much more vibration, but will not last any longer than a conventional battery of similar capacity and cycle-design.

So the net is, IMO, asking others if pulleys worked ok for them is not usefull in predicting how pulleys will work for you. The specifics of the car (alternator capacity at idle), the climate, the battery design/capacity, the actual daily driving conditions and the actual habits of the driver ALL INTERACT UNIQUELY to determine if the battery is operating [too] deeply into its reserves or not on a regular basis.

To the extent it is, is to the extent your battery WILL fail prematurely, and how prematurely.

The engineers who designed the car took great pains to assure that you don't inadvertantly, and on a regular basis, dip into that reserve deeper than the modelled use scenarios of the car and working design parameters of the total electrical system permit.

When you change pulleys you fundamentally change those relationships: some under most conditions, but mostly under idle/slow-speed conditions. Depending on the above use factors, two identical cars can experience vastly different lifespans and failure rates for various electrical components with altered pulleys. Fortunately most will only see a shortened battery life and some will see almost no change, but others can and will see battery and component failure ---

---IT ALL DEPENDS...

 

So what should the idle be set to for the UDPs?