Is chip needed when changing to 3.73's?
 

I am definetely going with 3.73's for my first mod. What is the deal with chip/speedometer/odometer issue? My mechanic is telling me that a super chip ($300!)is needed to fix speedo. etc. I hate to buy a stupid chip when I plan on getting a blower at some point and of course the chip would be useless then. If you guys say the chip will help performance for real then maybe I wouldnt feel so bad adding one. Is there any other way to fix speedo problem besides this chip? Is there maybe a better chip for the same price range? What about custom mapping like saleen offers? Also, I'm getting all sorts of warnings about bad bearings being discovered in GT's when rear end is pulled and to expect extra expense. Geesh, maybe I should just get the damn blower. Someone email me $5000, thanks.

I am not sure about the chip, but I did have to replace the carrier bearings in my rear end. They were making a roaring noise. While they had the diff apart, I had them install some 3.73s. If you are not hearing a roaring noise from the rear of your car, you bearings may be ok. The ones that came out of mine were pitted pretty bad.

------------------
'97 Cobra, Rio Red, MAC Cold Air Kit, 3.73s, NGK V-Power
BBK H-pipe w/cats (Coming Soon!!)

You will need a speedo compensator. I know Sean Hyland Motorsports sells one, but there is another place that has them cheaper. Maybe Dallas Mustang?

oop - what year is your car? Newer cars use a speedo compensator, older cars you have to change the speedo gear.

lemme post my sig-while I'm replying-how does gear mod affect warranty?

------------------
Black 2000 GT,5 spd,17" wheels,mach,leather

The rear gears on mine were shot when I took it in to the dealer for a tranny problem. As soon as they heard it, they told me they needed to be replaced (unfortuntely by the time I heard the message they had already put in the same gear ratio and I couldn't have them upgrade them at the same time http://www.mustangworks.com/msgboard/frown.gif ) With the ragtop, I couldn't tell the difference between the gears and road noise... good thing they could.

As for warranty issues, I would think that if you have a dealer put in FMS gears it would be ok, but I would ask them directly just to make sure.

------------------
98 GT Conv: K&N, Pro-5.0

Blue00GT: Thanks for the intro to Dallas Mustang. I had a great talk w/ one of their salesmen who owns the same exact car as me, and his first mod was 4:10 gears! He swears by them and said his buddy has a 99' Trans Am who before the gear mod he could hang with until 3rd, then the T/A would fly by. With the 4:10's he swears he dusts his buddy every time! Also, DM sells an in-house fabricated speedo compensator for $99 (the cheapest I could find elsewhere was $145!). I'm stoked for the savings and am going with 4:10's. I dont get on the highway much and when I do I'm floored in 4th anyway struggling to pass VW busses. I also ordered redline synthetic gear and trans oil. My only worry here is when I go to Dallas and late at night cruise the incredible cop-free 15 mi. long straightaway called "North Dallas Tollway" and run in to the Porsches and BMW's that prowl there and run out of revs at 120 or so! (We used to race up and down this road at 4:00 a.m. at 150+ mph in college, cops have nowhere to park on this road!) Anyway, I'm going for 1/4 mi light to light performance instead of top speed.

Or even scarier, you could run into a yellow SN95 GT that just had a few thousand dollars worth of engine mods put into it.... j/k

STILL waiting to get my car back...

(400 horses at the ground, drag radials, and a taste for rice...)

------------------
"The Yellowjacket"
Ricer 1: What the heck was that!?
Ricer 2: I don't know. It looked kind of like a yellow SN95 Mustang.
Ricer 1: Nah, fast SN95 Mustangs don't exist... Must have been a mirage or something...

I'm not too fimiliar with the speedo's on Mustangs but with the Camaro's, all we need to do is replace the drive and driven gears located behind the tranny. These two small gears cost about $13 (total) and can be installed in about 30 minutes. This applys for both cable and electronic driven Camaro's.

------------------
1992 Z28 TPI.
160' stat, Accel 8mm, Accel Cap & Rotor,
Flowmaster, high-flo cat.
700R4, 3.73s HD Zexel Torsen

Dude I feel your pain man its soo much more money to calibrate the speedo's on the newer breed of Stangs then compared to O.G's (Original gangster, for those of you who don't speak a little ghetto=) )

I found that you can either get a chip burned or you can get an ERA (electronic ratio adaptor) from Abbott assuming that you have a 98 and up. What year is your Stang?

------------------
Yours in SPEED=======
Mandy aka GTGRL00

Am I crazy to decide on 4:10's? I was talked into it, I hope I dont rev too much when on the highway (I drive 15mi each way to work on I35, other than that I dont get on the highway). It seems like most people are into 3:73's. I really dont mind a few extra revs in exchange for decreased (cheap) 1/4 mi time and overall improved response (I hate the stock gearing-way too tall). I havent'installed the 4:10's yet and could easily return them, I'm just looking for some real world input from someone (other than the DM salesman) who has tried both ratios.

------------------
Black 2000 GT,5 spd,17" wheels,mach,leather

I have 3.73s and love them. I have never had 4.10s so I really can't compare, but I can tell you that the 3.73s made a BIG difference, especially noticable down low where the mods need it.

------------------
'97 Cobra, Rio Red, MAC Cold Air Kit, 3.73s, NGK V-Power
BBK H-pipe w/cats (Coming Soon!!)