blue2000Z28

Well I understand that the 60E has a higer first gear that the 80E. FLT has a 2:75 first gear option. When I get the trans, if I dont opt for the gear option(2:75) how much difference is there going to be? If converter size matters then it will be a 4200-4500.

I just dont want the car to be a dog off the line. Thanks

12secSS

iTrader: (30)

Same as the TH400 ...

2.48
1.48
1.00
.75

NO-OPTION-2002

iTrader: (2)

4L60E/4L65E/4L70E/700R4

1st 3.06:1
2nd 1.63:1
3rd 1.00:1
4th 0.70:1

4L80E/4L85E

1st 2.48:1
2nd 1.48:1
3rd 1.00:1
4th 0.75:1

TH400/3L80

1st 2.48:1
2nd 1.48:1
3rd 1.00:1

TH350/TH350C

1st 2.52:1
2nd 1.52:1
3rd 1.00:1

200-4R

1st 2.74:1
2nd 1.57:1
3rd 1.00:1
4th 0.67:1

NO-OPTION-2002

iTrader: (2)

For most people, the taller first gear of the 400's / 80E's help them to not spin out of the hole.

cbrich

Another question is, can you adjust the computer for the lower first and second gear? Or will you have to get a stand alone engine computer and stand alone tranny computer?

joecar

This puts 1st gear closer to 2nd gear, so engine RPM will drop less on the 1-2 shift (higher RPM = more torque to start pulling in 2nd).

2.75:1 is lower than 2.48:1 so you'll still get more pull off the line.

blue2000Z28

ahh. I see. So would it be worth getting? It is a $500 option.

Thanks guys for all the responces and help!

cablebandit

iTrader: (37)

i read (dunno if its right or not) that for some unknown reason, you cant use it with a stock/modified stock pcm...dunno if it throws off the speedo/shifting stuff or what. Who knows what the calibration stuff for the 4l80e has that we dont see. If it can be done, I would only do it for mileage. It does drop your city mileage with the 2.48 1st gear. As far as the track, my car went exactly the same times with the 4l60e vs th-400 (same 1st gear as 80e)...60' the same...330 the same and all...I was surprised. Like i said...research it and do it for mileage only.

joecar

Sorry, confused about which trans is offered with 2.75 first gear.
Is the 2.75 first gear on the 4L60E or the 4L80E...?

cablebandit

iTrader: (37)

2.75 is a 500 dollar option for the th400 and 4l80e. the 200-r4 comes with it stock

cbrich

The 2.75 first gear is great, it helps a lot. I have the lower first in my Camaro but the tranny has its own computer. I would like to add the lower first gear to my truck, but I am not for sure if the oem computer can be programmed for it.