New Gear?

Is gettin a new gear a good investment...if so what kind is the best to get for example 3.73 or 4.10? i dont know much about them just that they up your low end torque. i have a 98 TA with just exhuast so far, give me some info...

What are you trying to accomplish by changing the ratio? Do you need more acceleration? Changing the ratio is not simply bolting in a new ratio - there may be adjustments and shims to install - not inexpensive.

Some things to consider: Is your car a manual or automatic? If manual, changing the axle ratio will not impact mileage as much as it would the automatic, because of the two overdrives in the manual. How are you going to recalibrate the speedometer? Will the computer need to be told about the change?

Assuming you have the 5.7L engine, can you spin the wheels on a start (I would hope so)? Maybe adding wider tires (but keeping the same circumference) or softer tread would be better than changing the axle ratio.

my TA is 5.7L and i have automatic transmissiom im lookin for more low end torque...

gears dont give you any torque at all they only up your rpms so you hit your peak power quicker see this RPM calculator : to see the diff RPM at diff speeds http://www.chevellestuff.com/generic/rpm_calculator.htm

put in your info and then find out which would be a better choice to go with the 3.73 or the 4.10s

right off the bat the 3.73's are your best bet or even 3.55's so that way you can still do some highway driving easily

if you want more torque get some bolt ons or even geta new intake manifold

gears will give you accelaration not power

I'd go with a 3.73 setup myself (and plan to hopefully this spring). 4.11's in an Auto would be pushing it.

And when it comes to torque, you do in fact increase the torque output when switching to a lower and shorter (numerically higher) gear ratio.

It is actually a mathematical equation - you are literally multiplying the torque with shorter gears.

I put 3.73 rear gears and an Eaton Posi in my '96 last turkey day. I had the PCM tuned to recalibrate the speedometer. Not a big deal. The whole thing cost about $900. My gas mileage sucks now... but I have instant power at highway speeds. Rather than wait for the RPMs to build when I had my 2.73 stock rear gears. Plus, I have a 2800 stall converter. If my car had wings it would fly when I punch it highway speeds! My advice, go with the 3.73, but remember you'll lose top end speed by as much as 10-15mph, but you'll gain power thru the RPM range.

would i need a new posi? and how much is the PCM tune and where would i get it?

If you go with significantly bigger gears than what you currently have you might have to get a bigger posi. For instance, my '96 Formula came with teeny-tiny 2.73 gears and I jumped up to 3.73. The stock posi is a series 2 and the posi that acepts larger gears is a series 3 I believe. Someone correct me if I'm wrong. On your '98 TA you might have 3.23 rear gears. You're vehicle codes will tell you that if you don't know. If you do have 3.23 or higher gears you might not have to get a diff posi. At any rate... You'll also want to get stock GM gears... the Chevy S-10 pickup came with an optional 3.73 gears. Find a set of used gears from the S-10. Don't go with Richmond or any aftermarket supplier unless you don't care about gear whine. It's the added nickel they used in the casting of these aftermarket gears that cause vibration and "whine". I've heard a bunch of people say they didn't like their aftermarket gears... but plenty others don't care. I think the added nickel actually makes them stronger than stock, but you sacrifice a little noise. So that's up to you. Stock 3.73 will hold up just fine in my opinion. I bought my ring & pinion off of Ebay for $60. I went with an Eaton posi differential which costs about $350, plus the incidentals such as seals, shims, fluid, etc... not to mention labor. But this is one of the BEST mods I've done so far. I've done a ton of crap to my car the best mods I've done are headers, 2800 stall, and 3.73 gears. All those "free" mods aren't worth crap for what you ultimately want to do. As for PCM tuning check out www.madz28.com or www.pcmforless.com I've dealt with both and have had much success and happiness with both. You actually send them your PCM and tell them what you want. This kind of off-the-dyno style tuning is very easy. I just wouldn't have them mess around with my air-fuel-ratio, but they say they can do that as well. For that, I stick with a shop that has a dyno and can tune the car on the dyno as every car is different. I believe Hypertech also makes an inline sensor you install on the trans case at the vehicle speed sensor that tricks your PCM into thinking it still has your stock gears but recalibrates your speedo so it's correct. Don't know the pice on that, but worth a check if you want.

Its most likely that the carrier is a 2 series - although I'm not sure if he does in fact have the 3.23 axle upgrade (that could be a 3 series - most 2 series aftermarket differentials can fit 3.08 or lower gears, some say 3.20something or lower).

Most cases us guys with autos always had to change to a 3 series carrier. I happen to have found 3.73's (and others) that fit 2 series carriers. They're made by Strange. Here is a link:

http://www.thunderracing.com/index.cfm?fuseaction=subcategory&subcategoryid=1062

Whether or not to replace the differential? Depends on how much you've beat the shit out of the stock one. I would definitely recommend a bearing change. Most reputable shops I know will not reuse the bearings unless the car is new.

Eh LT4, which Eaton posi did you get and why? I'm looking into aftermarket diff's and can't make up my mind.....

I went with Eaton P/N 19599-1. I looked at the Auburn diffs, but kept hearing great reviews and satisfied f-body owners that bought the Eaton. Talked with a couple of local F-body speed shops and they recommended I go with Eaton. I even talked with some suppliers that carry the whole range of diffs and the supplier even recommended I buy Eaton. The cheapest place I found on the web was www.nationaldrivetrain.com They list as $354.95 for the EATON POSI GM CAR & TRUCK 10 BOLT 7 5/8" with 2.73 & UP gears for a 28 splined axle for 1988 to present vehicle. However, I actually bought the posi from the Ring & Pinion shop that installed the gears/ posi becuz they had the posi in stock. They charged me $350 for the posi... so I guess I saved a few pennies on shipping/ handling had I bought it mail order. I decided against a 12 bolt, becuz I couldn't justify the added expense just to run slicks/ stickies on the weekend. Besides the Eaton is rebuildable anyway. But I'll slap on some BMR boxed lower rear control arms and a set of HAL QA1 adjustable shocks and preload the hell out of it when I want a better launch. Perhaps in the future I'll upgrade to a 12-bolt, but for now I'll stay away from drag radials, and stickies.

so ur sayin in order for me to get a 3.73 gear i may need a new posi, ring and pinion?...how much will all that cost me?

and how much would this take off my quarter mile/0-60 time?

As for cost... that depends on if you buy new ring and pinion or used. Like I said before, I bought a set of genuine GM 3.73 ring & pinion from Ebay for $60.00. If you buy them used and want to confirm they're really 3.73 gears, just count the # of toothed-ridges on the ring and divide by the number of toothed-ridges on the pinion... or vice versa, but you'll know for certain once the math reveals itself. If you buy new, a ring and pinion can cost you upwards of $225+. The Eaton posi I bought cost me $350 and the shims, bearings, seals and fluids/ additives was probably another $100. I also bought a brand new OEM cover and spray painted it with high temp chrome ceramic paint. Can't see it when I'm driving, but when I'm under the car I sure notice it. The cover was an additional $50. Altogether with parts and labor I spent roughly $800. Make sure you find a good Ring & Pinion mechanic shop. I've heard MANY scare stories of improperly installed gears. Not really sure what I expected with the finished product, but I was amazed at how much faster my RPMs spun. Before I had them installed, I probably cruised on the highway around 2000RPM, now I cruise close to 3000RPM. I was a bit shocked by that at first, but soon learned that I had instant power when I whomped on the go pedal. I didn't have to wait for my RPM's to build and when cruising I'm never far from my 2800 stall lock up feature and when that hits, I'm OUTTA there. Can't speak on times cuz I haven't been to the track since I had it installed as I had it installed around last Thanksgiving. I imagine my 60' times will absolutely suck until I learn to feather the gas and not torque brake so much, but my ET will definitely improve. Just messin' around on the street, I lost to a ZO6 becuz I couldn't hook at the light. He pulled on me from the line while I spun my tires. As soon as I let off the gas and hooked he could pull on me anymore, but he had two car lengths on me from the start. I imagine a better rear suspension (stiffer) (IE. lower control arms and adjustable shocks) will help me plant my tires more firmly. Good luck! You will DEFINATELY be pleased with the results!

so just from addin a new gear with other necessary parts, you dropped about a second off your 0-60? and what is a 2800 stall lock up?

Whoa!!! I never said it would drop a full seconf off me E/T. BTW- the 0-60' time is how fast you travel the first 60' in seconds. A respectable 60' time is under 2 seconds. (Ie. 1.8 or so) It's not the entire quarter mile. The 60' is a gauge of how well you hook off the line. Like I said in my previous email, I imagine since I got beefier gears but still have the stock 10 bolt design that I'll have to really feather the gas, otherwise I'll just spin my tires, cuz I have so much torque feedin' into them.

As for the 2800... I'm talkin' about a torque converter. It installs in the automatic tranny and you can do it yourself if you have the time, patient and dilegence.

well i meant how fast you travel from 0-60 mph...and what cold air inductions of these two would you suggest.....
http://www.lmperformance.com/2909/1.html
http://www.lmperformance.com/3041/1.html

OH- I've never timed that.... go figure. But that would be nice to know, you're right. As for which CAI system, I'm all about functionality. Make that awesome hood of yours work for you. The Volant system scoops air in thru the snorkler hood design while the SLP version uses the bottom air dam to feed air into the air filter. I've seen people with both. And personally I think the Volant system just looks more "trick" under the hood.... in my opinion.