Who here has had a gear swap?

[99silveradoSS]

I see there is few of people from the LS1Tech.com site here.

If you have had a gear swap, could you tell a big difference? Any 1/4 mile times?

I've got 3.42s and was thinking about going to 3.73s later on this year.

[Tiburon]

You will probably see a 2/10th reduction in the 1/4 ml going from 3.42 to 3.73. Make sure you put an Eaton posi in there while it's open.

[99silveradoSS]

I plan on it, thanks ;)

I might do the 2600 Yank Converter first...time will only tell, especially the way I am! So with the 3.73s and 2600 stall, I'm thinking .5 - .6 off of my 1/4 on street tires, right? IF I were to go with 3.90 gears, .6 - .7 off, right? Then after the headwork, maybe another .2 - .3 and then, after some drag radials, I should be in the high 13s. At least that's what I'm thinking.

[onyx silverado]

i have the 4.10s.... but i threw 20's on so i didnt see any difference in track times... heheh.

[BigKID]

We threw some 3.73 in a buddys ext cab and he said it was much more responsive than with the 3.42. Havent gotten any track times yet though.

[gremlin]

I went from 3.42s to 3.73s on my truck, and I could tell a slight difference in acceleration. If I were you I'd put some 4.10s on it. Definitely put the stall in first... It's much more fun :D

[ANIDOTE 00]

If you put the stall in before you do the gear change, when you do your gear change you will loose some of your flash stall espiecially if you go to 3.90 or 4.10! So in my opinion I would do the gear first and when you get your stall you will see more of a gain with it and you won't double dip your self! ;) I see that you live in Bossier, we need to hit the track up one night! :drive: Your truck is the Burgandy and Sandstone right? If so, I heard it the other day and it sounded DAMN GOOD! :thumbup:

Later,
Cole

[01Thunder]

I went from 3.42's to 3.73's and also installed a posi at the same time.
truck became very much more responsive
i love it. i went with the 3.73's instead of the 4,10's because of the highway driving that i do.
not about 2 weeks later i installed a vig 2800, which flashes up to 3200.
and lets just say "holy crap batman!"
I drop almost a full second off my 1/4 mile times with this a some tuning.

[99silveradoSS]

ANIDOTE 00: My truck is Burgandy and light grey, it has some performance stickers on the back and a FMS sticker on my eyebrow. Was it me? I heard yours at a gas station a while back and it sounded awesome! Yeah, we'll have to hit the track up in a month or two, after another mod or two!

Gremlin5.3: Do you like the 3.73s?

BigKid: Did your buddy feel a difference all over the powerband or just off the line?

Thanks for the info Guys!

[ANIDOTE 00]

Yea true dat, true dat! :thumbup: It was you I seen. I also forgot to mention that if your runnin a 26" tall tire with a 3.73 gear it's like runnin a 3.90 ratio. I have 3.73s and a 26" tall tire and I like it! If your just looking for 1/4 mile runnin I would go with 3.90 or 4.10, depending on how much highway drivin you do. ;)

[99silveradoSS]

Thanks for the compliment!:D I'm running a 265/70/16 tire size and that's suppose to be a 30.6" tire, I've tried to measure it and got a little bigger. I did a tire/gear calculator thing on the internet awhile back and it said my gear ratio was a 3.3x because of the bigger tire.

Do ya'll think I should go 3.90s? I just want to be able to puch it around 60-70mph and haul ass!

[ANIDOTE 00]

If you're going to keep that tall tire I would run a 3.90 ratio. You will fell that all the way through the power band! Now I've heard that when you do a gear change that you loose hp on the dyno but get quicker in the 1/4 mile! :D So don't be disapointed when you go to the dyno after the change.

[BigKID]

You should get the benifit of gears throughout the power band and gear range.
I have 3.73 and really wish I had just a little more gear. I think 3.90 would be a happy medium betweend the highway economy of 3.73 and the haul ass factor of 4.10. If I ever change mine out it will be with 4.10.

[McRat]

I put 4.10's and a posi in my Ford (stock 3.55) with 245/75-16's, and it actually got BETTER mileage on the freeway by 1mpg. Why? Even on slight grades it would down shift into 3rd. With the 4.10's it doesn't "hunt" as much.

Don't know if that applies to GM, but 4.10's are good truck gears. Excellent for towing and stoplight warfare.

[gremlin]

Do you like the 3.73s?
Yeah I like my 3.73s. They are a definite improvement over the 3.42s. But like I said earlier, if I had to do it over again, I'd go with 4.10s for a little more umphh.