3.08 vs. 3.42

[roddyrod_72]

I have a '98 Camaro with stock 3.08 gear. I'm fixing to put in a 3.42 gear. Has anyone done this before...exactly how much difference does it make on acceleration? I know it seems pretty sluggish right now with the 3.08. I drove a '95 3.4 with 150k on it and it felt stronger than my car! And also, how much trouble is it to get your speedometer recalibrated? I would appreciate any reply...thanks!

[hawgs]

this one is gonna be moved to the drivetrain forum... but yeah going from 3.08s t 3.42s will help, do a search and youll find a ton of info on it [img]smile.gif[/img]

[bu-bye]

moving... [img]graemlins/toto.gif[/img]

[Sean37]

It supposedly makes a big difference in acceleration. I have heard that a stock 3.8 with a gear change from 3.08 to 3.42 will drop the 1/4 mile time from 15.8 to 15.2, so you will gain about a 1/2 second in the 1/4 mile. The speedometer recalibration is not so easy from what I have read here. I've heard that the Jet SCU 2000 can recalibrate the speedometer and shift points for you but I don't know how well it works. I want to do the same gear swap as you some time but I want to be sure that it wont screw up my speedometer.

[Only4U]

ARG! not that these questions piss me off, but i SWEAR TO GOD i answer this question AT LEAST twice a week. ok, if you check the TECHNICAL ARCHIVE, dom posts this info about gear swaps, but i will tell you from personal experience.

the switch from 3.08s to 3.42s is a good solid change. 3.42s are kind of the all-around gears because not only do they have quick off-the-line acceleration, but they have good top end as well. if you are planning to do heavy modding on your car, gears will have to eventually come.

secondly, you CANNOT get the shift points corrected on an a4 UNLESS you get a dealership to recalibrate your pcm--which is technically illegal to do. if a dealership says they will do it for you, you've got to have a VIN from a car of your car's year that carried the y87 package and then your pcm can be reset (or a VIN of a car that came stock with 3.42s). this can cost anywhere around $100 to do. jet scu2000 doesn't do anything but recalibrate the speedo and some people say you can toy around with the tire size settings and such to make the shift points better. i have done the 3.42 to 3.08 swap and have no issues with my shifting. i've also heard that some people that do the same gear swap will sometimes hit the rev limiter at WOT...now how some cars do this and some don't, i couldn't tell you; BUT, you probably won't have a problem with the shifts being to harsh and it will, for the most part, be unoticable. now for god's sake, may a mod please put this in a tech archive or something so that everytime someone asks this question we can direct them here ? :D thx.

[mdchaser]

I just switched form 3.23s to 3.42s. Definately worth it, especially if you have 3.08s. Call up rksport and order the gears and an lsd (only an additonal $100 and well worth it). Good luck!

[ravenp]

Hey Only4U, it wasn't even a month ago that YOU were asking these same questions about gears 2 times a week, so go easy on the guy huh? [img]smile.gif[/img]

Anyways, good luck with the swap.. 3.42's are the way to go if you're a daily driver. They're next on my list [img]smile.gif[/img]

[Only4U]

<blockquote>quote:</font><hr> Hey Only4U, it wasn't even a month ago that YOU were asking these same questions about gears 2 times a week, so go easy on the guy huh? <hr></blockquote>

good point, i'm just saying that i think it would be a wise idea if a mod made a discussion like this in the tech archives as often as it is asked, you know what i mean?

[ravenp]

Yeah i agree... It would be great to have one central 'expert' opinion on this stuff. But that's hard to do when it comes to cars because there isn't one right answer.

In my opinion that's what makes this board so cool is that we have lots of knowledgeable people with lots of experiences to share.

My advice to anyone who is sick of seeing the same posts over and over again is, ignore them, let other answer.

Every day we get new members and in time they get to know thing and can answer those questions for the newer folks. It's an endless cycle : )

Sure, still encourage people to search, but otherwise, just leave them for others to answer.

my 2 cents anyways...

[AMinor65]

I've been toying around with my JETSCU2000, I think that you can get it to work, along with decent, near-stock shifting duration. Not shifting too early anymore, because the speedo is near correct. Basically, what I did was leave the stock and modified gears set to 3.08, stock tires set to 26, and modified tire set to 28. My stock tire size that came with the car was 26.2 (215/60/16) and my modified tire is 25.6 (245/50/16). My speedo is off by around 2 percent, and the cruising rpms in fourth is within limits so I don't set the tranny slippage code (SES light, scary firm shifting). Converter lockup is close to normal. May take the modified tire size to 29 (setting 6) after further testing. Never could get the thing to work right, using the instructions.

Gears are the best investment you'll ever make.

The only reason I kept playing with my scu2000 is because I'd already bought it. I would look for a y87 pcm from a junkyard. People are getting them for 60 to 80 bucks.

[Only4U]

<blockquote>quote:</font><hr> Not shifting too early anymore <hr></blockquote>

if you go higher gears, it shifts later than when it's supposed to. you'd could actually notice your shifts to be different? i usually cannot and have never set off any codes.

[AMinor65]

<blockquote>quote:</font><hr>Originally posted by Only4U:


if you go higher gears, it shifts later than when it's supposed to. you'd could actually notice your shifts to be different? i usually cannot and have never set off any codes.<hr></blockquote>

If you go to numerically higher gears (ie. 3.08 to 3.42) without pcm recalibration, your car will shift sooner because the speedo moves up faster.

If not, then your gears are not numerically higher than what you had.

That's why people complain about their shift points after new gears are installed. ;)