LT4 F45

Gear 4.10 4.30 or 4.56?

--------------------------------------------------------------------------------

So, i have plan on going for 4.10 gears on my 96 LT4 but the specialist that i when to recommend me to go for 4.56 since i have a 6 speed...
I im now in a dead end on what to do since all what i read on the forum goes toward 4.10's but it is true that 4.30 or 4.56 will only do better on the first 4th and we do have a 65 speed limit here that is highly looked at and costly over 75 so for a 1300$ investment i want to do the right choice on the first time... In my own idea i was going for 4.10 but now i need your opinions and experience on this to close the deal.

I dont drag race the car but i want to get the feel of power every time i need to...
I will not do any long trip with it.
The car is not a daily driver, i will only do like 3K miles a year and it will spin 2K rpm at 75 so still pretty good if i compare this to my 79 that was doing 3100 at 60!...
I also have 2003 Z06 wheels with 295 18'S/265 17's Potenza RE760's so that might change the calculation too!
Thanks!

WVZR-1

You need to remember you're dealing with a D44 (Super or HD). I believe there's a .56 in the after-market but NOT Dana/Spicer, I don't recall a .30 ratio. Dana/Spicer "branded" the ratios are .73, .91 and 4.10. I do believe there's Isuzu in a .10, .30 and .56 which would be Dana/Spicer that were available but I believe they might have been built for a 4 series case. Am I sure? NO! They would likely also be expensive! There's a couple Jeep that would work but Jeep changed the ring gear bolt diameter first to 7/16 and then to 1/2! Nissan I don't believe offered anything in the 4+ ratios.

Vettete/Viper gear sets are done for a 3 series. Now if you don't mind a "sleeve" on the pinion and using a "lesser splined" pinion flange the ratio availability changes. All conventional D44 ratios would be available for use with the "sleeve"!

The .30 gear sounds interesting!

ddahlgren

Sounds like the old if a little is good more is always better thing. If you can't hook it up what does it matter? Usually more gear is coupled with much better tires and if funds permit in real race cars different ratios in the transmission to pack them closer together. Endlessly smoking the tires is fun for about a weekend then it gets old. With a stock engine and street tires running to much rear gear can get as tiring as the exhaust drone. I would find someone that has run the 4.56 setup on a car similar to yours and uses it like you plan to and get their opinion or better a ride in the car.
Dave

hgh pwr

the 4.10 is the best ratio for the 6 speed cars,the other gears are too steep in my opinion.

There are a lot of guys that have 4.10 and just love it,you will feel the power.

Your engine will be reving too high with the steeper gears.

miker2

i have the 3:90 in my 90 and it drives great.

shakedown067

Do the 3:90s or 4:10s and call it a day. I think you'd be disappointed with anything taller and the lack of rear grip unless you are running drag radials or dot track tires. And if you are running super sticky tires, that's when you start breaking other stuff.

cv67

unless you feel the need for a 28 or 30 in tall tire because you cant hook forget about anything lowe than 4.11

Yours is probably 26 in tall, a 4.11 is plenty low enough to pull hard and 6th is just workable. Especially if your motor is stock dont want to go through the torque band too fast or a well driven car with a 3.45 will walk right past you.

If you got a cam with say 260@.050 duration then lower gears (4.56) youll need Too much is as bad as too little. Doesnt hurt to ask though.