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Discussion Starter · #1 ·
I have 3.42's on my 4.8L with 255/70's (30")

I want some more "get-up" but I don't want to lose a whole lot of top end.....

Is there a big diff between the 42's and 73's?

Would a new Torque converter help out any?
 

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HOT AIR BALLOON OWNER
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A converter will be WAY better than a set of gears ever could be...a quality converter will increase torque via a higher STR and get you into your powerband quicker.

If you plan a taller/heavier tire later...a 4.10:1 is a wise investment.
 

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Broke
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I disagree, whether one is better then the other depends on the setup. I bet you would be much happier going with 4.10s then if you did a TC swap.
 

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HOT AIR BALLOON OWNER
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Well a 3200rpm Vig w/ a 4.10:1 is too much gear for that much stall with 28-30" tires.

Gears won't help you launch much faster from a dead stop...a converter will.

A converter will help that big split between 1st and 2nd gears also, gears won't.

Unless you're running heavy tires/wheels... gears won't help as much in the 1/4mi either as a stall will.

Gears (4.10:1s) will cause some topend loss as you don't have the power to push them...like being over geared if you will.

I'd take a stock truck with only a Vig 3200 vs your stock truck with only a 4.10:1 and I'll eat you alive on the streets. 0-60mph, kickdowns, upshifts, etc.
 

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Broke
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I. Going to a 4.10 would help you get out-of-the-hole quicker.
II. They won't kill as much top-end as you think.

I don't know which would make you faster, but I know they would both make ya happier and make a big difference. 3.42s aren't that bad, it could be much worse. IDK, maybe because I have daily drove a car with 3.73s (28" tall tire) and 3200 RPM TC. To me it's a little bit high for daily use, but to each their own.
 

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Burning Rubber
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4:10 :imo
 

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HOT AIR BALLOON OWNER
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brodystruck said:
I. Going to a 4.10 would help you get out-of-the-hole quicker.
II. They won't kill as much top-end as you think.

I don't know which would make you faster, but I know they would both make ya happier and make a big difference. 3.42s aren't that bad, it could be much worse. IDK, maybe because I have daily drove a car with 3.73s (28" tall tire) and 3200 RPM TC. To me it's a little bit high for daily use, but to each their own.


You're not going to cut nearly as good of a 60' time with a gear swap to a 4.10:1 from a 3.42:1 with a stock stall ~1800rpm. It's not going to happen as you can't pull from a dead stop. That stall would put a soild truck length on you from the hole...hell even a 2800rpm one would.

With a 4.10:1 you're going to sit down in the 1/4mi with a bolt on truck as you'll shift into 3rd gear and just cruise past the mark. Unless you have heavy tires/wheels you really don't need it unless you're going to pull high RPMs. It's going to hurt when you're running that far.

Also... with a 3.42:1 gear it's going to be able to downshift back into 1st gear at a higher MPH from a roll to beat you instead of being stuck in that flat spot around 3300rpm in 2nd gear. It'll shoot right on by.

I've owned plenty of vehicles over the years...most radical ran 4.10:1 gears, 26" tires, and a 3200rpm Stallion PI converter. The cam was a 282/282 dur with a 110LSA...so I know about lope too.

I'm not saying 4.10:1 gears are bad, but a stall is a better investment for ET reduction/street performance.
 

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yes, i agree with hitman. a TC is a better performance investment than gears. a TC will also give you more rpm on upshifts. but remember, with a higher stall, traction becomes a problem off the line. most guys prefer a 3000 stall. myself, im more than happy with the 2600 i have. i can spin all through 1st, and im not about to run the nitto 555r on the street. too much $$$. if you're 4wd, then traction isnt as much of a problem - get the TT3000 if you tow, or something more aggressive (maybe from PI) in the 3000+ range.

short summary - get a TC first and decide if you still want gears.

that being said, i still want to swap out my factory 3.73 gears and locker for an eaton and 4.10s.
 

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Discussion Starter · #9 ·
SO you guys think a 3200 rpm stall would be too much for my stock truck?

If i go the TC route, I want something that'll be good for my stock setups but also be beneficial when i do upgrade gears and add some bolt ons
 

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HOT AIR BALLOON OWNER
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You'll need a tune with that fat of a stall due to the potential for misfire codes and to control TCC lockup.

3200rpm... depends on what size case, STR, etc. to determine how it's going to drive as well as how much power you are making and how heavy your truck is.

I have an 11" 3000rpm stall, 2.21STR in ~5500lbs Z71. It's fine for a truck like mine, I wouldn't be scared of a 2800-3200rpm PI Vig for a RCSB truck tho'.
 

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Broke
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In what conditions? Test this at the strip? I have had a few vehicles that have gotten gear swaps to lower gears (numerically higher), and I can't say that I have lost top-end.... Gears go quicker but ya just shift into another one, so it's no biggy if I spent less time in each gear.

**I am speaking about speeds under 130mph though.

IDK though i aint too familiar with all this technology and how it plays a role in transmissions and engine characteristics (more used to carbs and built autos and manuals....) :crazy: :pow:
 

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the general rule is if its not a track whore truck....

3.73's = auto
4.10's = manual


i say you compromise and do 3.73's and a 3200 stall. :rocking: :D
 

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HOT AIR BALLOON OWNER
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onyx said:
i have a TT3000 waiting to go in... i cant wait to see how much my 60' drops....


You sound like me. :D

I'm trying to decide 4.10:1 or 4.56:1 for my Z...I'll never run it at the 1/4mi but maybe at an 1/8th. I'm about street performance from 0-90mph or so...
 

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HOT AIR BALLOON OWNER
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Remember I have 33" tires... :think:
 

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HOT AIR BALLOON OWNER
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