5 spd to auto conversion, what should be expectations be?

[Boost-n-Juice]

I converted from T5 to a SB C6, fully rollerized, reverse manual VB, 4k 9" stall.

 

Now I realize I lost an additional 5-10% rwhp.

 

Here are my questions...

 

It feels like Im losing more than 20-25% between the motor and wheels. and the shift is quick but not harsh. Just guessing, but it fells like a lost 80-100 rwhp.

 

I know a C4 is more efficient but I have a C6 so, that's just the way it worked out. Should the shifts be hard and solid? Should the shifts be Harsh or violent? Is there a way to externally adjust the line pressure on a c6?

 

I'm just very disappointment at his point. My car feels atleast 1 second slower in the 1/4.

[88lx5oh]

oh why in the hell did you do that

 

dont know if this will help out or not,

 

but swapping my 88lx from a aod to a t5

only mods being a full exhaust, 3.73 gear, and CAI

 

i was a sec faster with the t5 in the 1/4 mile

[Dave1647545494]

shift frimness is controlled by the valve body you can adjust it some externally through the vacum modualtor on the side of the trans it should have a very small slot screw inside try giving it a half a turn or so clockwise and then drive it and see how it shifts...

 

you may also want to run a little more gear with the auto

[Tractor]

yeah changing from a 5speed to an auto is a big change. Not sure of the gear ratios of each gear in each transmission since I'm more of a chevy guy, but its pretty likely that you made a 15% change in final gear ratio. Not sure if you thought of that when you swapped or not. So you might have to change your axle gear ratio to compensate. If you gotta change the gears anyway now is a great time to put in a set that will really make you go. What does the car have for gears now anyway? 3.55 to 1? Not familar with to many fords. Another tought to consider is torque multiplication adds around 2.4x the final gear ratio while excelerating. At least thats how it works in the 4x4 world.

 

Evan

[Boost-n-Juice]

It's a Manual Valve body, no modulator. I have not spayed the car to see how that will effect things. It has 373's which is perefect. I think problem is the stall/cam combo. My cam isn't anywhere near as big or aggresive as it should be for this set up. I'm going to get a custom ground cam and slap the blower back on this winter.

[Dave1647545494]

i had good luck with a .600ish lift cam with around 312 deg duration and a 108 lobe center with that stall that was a big block though

 

with that big of a converter the motor needs to spin faster to make full line pressure 4.10 or 4.56 gears and the bigger cam would do wonders by moving your power band up 2000 rpm or so

 

you could also try changing converters go down to a 2800-3200