Does anything have to be done (retune, flash computer etc.) when installling underdrive pullies to the SN 197s? Or is it just a simple mod?

 

Simple mod, no retune necessary. The only thing you might have to worry about is several people have had issues with their alternator and or battery with the underdrives. It hasn't been widespread though, and appears to be a fairly safe mod for most.

And the chassis designation is S197, not SN 197, but close enough I guess.

 

Yes, fairly simple. The only specialty tool needed is a three finger puller but here are some other tips.
-An impact gun will make it a lot simpler (required for automatics)
-Make a drawing of the belt routing as Ford neglected to include a belt diagram anywhere

 

The pulley puller that you need is the Chrysler model, available at AutoZone for rent, and probably anywhere else you can rent tools from.

I've had the Steeda UDP's on 2 S197's now, with no problems whatsoever.

 

Make sure you have an impact gun with lots of torque! I had a hell of a time getting the harmonic balancer bolt off until I got a 650 ft/lb impact gun.

Pull the electric fan and shroud to do the job. It's only 2 bolts and a bit of finessing to get the fan/shroud out - gives you tons of access and makes the job as easy as pie!

Also, GET A NEW HARMONIC BALANCER BOLT FROM FORD! Do NOT reuse the stock bolt! Steeda says that you can reuse it once but I have read of horror stories of the original bolt shearing off when a second removal was attempted (ie, going back to stock HB for supercharger). A new bolt is a $5 insurance policy that can't be beat!

No issues with battery charging or AC here, and I have the Shaker 1000 as well.

 

Sears has a small 4" torque wrench that's rated at 250 ft-lbs also. I used that and did not have to remove the fan or shroud. That saved a lot of time.

I also found that positioning the three prongs on the puller and keeping them tight was very difficult. I used a rubber band to keep them together and it made the removel really simple.

Autozone will lend you the harmonic puller and the installation tool that aligns the balancer for installation.

The other tip you need to know about is the alternator bolt. It sticks out a bit too far and with the larger waterpump pulley, the bolt will shred the belt. You need to grind or cut that bolt.

I wrote up a set of instructinos with pictures and P/ns for the tools. Here's a link:

http://www.cherod.com/mustang/HowTo/Pulleys.htm

 

Next question would be, can you tell a difference in this upgrade or has anyone dynoed after making the change? In other words does it improve the already awesome performance of the car?

 

Thats a great question...how well do pulleys work?

 

I haven't had mine dynoed, but this time when I added them I hadn't changed anything else, and did notice a difference. The engine spun up a little quicker at full throttle, which made the first on ramp (2 blocks from where I had them installed) a bit more fun.

I take that onramp almost ever day, and hadn't gotten that much tire spin on it before.

 

I didn't feel any real difference... I must admit I was a bit disappointed after the install. While I wasn't expecting a huge new surge of power, the butt-o-meter didn't register more speed, acceleration, etc... Certainly not enough to justify the $200 or so I dropped for the UDPs...

Ah well, at least it looks prettier than the stock harmonic balancer and my A/C and alternator still work.

 

I noticed the engine seemed to spin up a little easier, a little less bogg feeling w/ the UDPs. I have a manual so feelnig the bogg when taking off from a stop may be a little easier than an auto.

 

+1

 

We keep plenty of Steeda's in stock ready to ship same-day!

CR
Tillman Speed

 

I definitely noticed the difference, especially on acceleration. I have a stick also so maybe that makes a difference.

I haven't had mine dynoed but others have said they get about 10 more HP.

 

I put the Steeda UDPs on in March and the car felt like it spun up quicker than before.

Last year I had a best 1/4 mile ET of 13.362 at 106.30 mph. When I ran it again after I installed the UDPs, I managed a 13.257 @ 109.36 mph. How much of that were the pulleys worth and how much was due to other misc variables (weather, etc.?), who knows for sure?

Other mentionable mods include C&L Racer CAI and Brenspeed SCT XCAL 2 93 oct tune.

Steeda supplies a new bolt to replace the long stud and nut combo Ford uses on that atlernator fastener mentioned aboe that would interfere with the belt or water pump pulley. If you just grind the factory stud, you might not be able to easily get it out when necessary.

 

I don't recall the exact #'s but I do remember watching the MM&FF video where they put pullies on (I think Steeda) and after the dyno picked up some decent HP. Enough so that I decided to reconsider about picking some up this year instead of waiting till next year.

 

Cowtown, just don't buy them from RPM outlet...

 

**** RIGHTS!!!! I'll retain the rant for the time being!

 

hey i just picked up a set from rpm outlet, fill me in..i still haven't put them on

 

If you already got them and they are the steeda UDP's, then you are ok. RPM is bad about either never sending them, or sending you something different than you ordered. Consider yourself lucky.