I have a question and I was wondering if anybody could help me. I did a 5 speed conversion on a 86 turbo 4runner. I got all the parts off of a 85 4runner(4 cyl). My question is are the gear ratio's the same in the turbo auto trans vs the 5spd manual trans? The truck feel's kinda in need of more power. Should I swap out the rear end as well?

 

Well, it's kinda hard to compare the two because the torque converter makes auto gearing "variable" depending on RPM.

Generally, autos have lower rear end ratios to accomodate the power loss in the tranny and the HUGE overdrive.

What rear end ratio and tire size do you have?

When you say it's in need of more power, are you referring to acceleration or top end?

Nice thing about turbos...power is only a wastegate adjustment away! LOL

 

I believe the gear ratios are the same they are 4.10s. I wouldn't expect too much acceleration out of these old trucks.

 

This link may help:

http://www.off-road.com/toyota/tech/other/4_dts.html

Scroll down for tranny gearing. Most of the 5 speed manuals have an approximate 15 to 20 percent over drive. The A340 series auto trannys have about a 30% overdrive.

Mike in AR

 

You can check what gears you have manually. Jack up the rear. Put a mark on a tire. Put a mark on the drive shaft. Have one person spin the tire exactly twice, while you watch how many times the drive shaft goes around. Take that number and divide it by 2. That is your gear ratio.
8 1/4 rotations = 4.10 gears
a little over 9 = 4.56
a little over 10 1/2 = 5.29
etc.