Thinking about going 4r70w in The Coyote Fox Body

svteezy

Member
Established Member
Joined
Apr 7, 2010
Messages
236
Location
Ocean Springs, MS
Well I have been thinking... I have my 86 mustang I just got done with putting the 2011 5.0 in and I went with a built T56 that I had done with all D&D Performance parts. I am starting to consider going auto for the best 1/4 mile times. Im getting aggrivated with the stick because of clutch pedal issues and other little things. Plus running a stick at the track a lot tends to be a little brutal on everything else. I priced a 2011 6 speed auto and $5000.00 without converter is nuts! not to mention the wiring and computer tuning would be pricey. So with that said I have been looking at manual valve body 4r70w w/transbrake and tc lock up. My only concern is the gear ratios in the transmission are no where near as good as the the 2011 6 speed auto. I just wonder if the car is gonna feel slow with the 4r70w. I know these cars perform really well with the new auto but its probably only because it keeps it way up in the rpms the whole time. I've been reading on the termi cobra forums where people go to the 4r70 but the are most of the time a turbo car with tons of torque. Main thing is I dont want to slow the car down... I need opinions!
 

Bad Intention

Member
Established Member
Joined
May 16, 2010
Messages
774
Location
Lafitte LA.
I had Lentech 4R70W in my 04 Cobra. best move i ever made. I got tierd of spending money on the T56 and clutches. One of the guys i race with has my 4R in his 750 HP cobra. and it still working great. I liked having O/D.
 

grnenvy

New Member
Established Member
Joined
Nov 27, 2002
Messages
3,486
Location
From Philly now Tampa, Fl
It would be real nice if u could put the new 6speed auto in this car. The gearing is awesome. I'm not real sure how you would control it unless you could get the computer and harness. Then you would have to find someone that could tune the trans shifts.
 

svteezy

Member
Established Member
Joined
Apr 7, 2010
Messages
236
Location
Ocean Springs, MS
I really wish i could do the 6r80 but it would just be a huge deal to make it all work and it would cost a ton. I can do the 4r70w for about 4 grand I think. I think with the right converter and gear it would keep the car in its power range. Im thinking 4.30 gears and around a 3600-4000 stall. What are you auto guys running with after market torque converters? I know circle D is the company I will use because they are proven to be the best in my opinion.
 

svteezy

Member
Established Member
Joined
Apr 7, 2010
Messages
236
Location
Ocean Springs, MS
I had Lentech 4R70W in my 04 Cobra. best move i ever made. I got tierd of spending money on the T56 and clutches. One of the guys i race with has my 4R in his 750 HP cobra. and it still working great. I liked having O/D.

Who built your 4R? I've been hearing really good things about Darrin Burch at BC Automotive. My friend has one of his in his turbo 3v and his car made around 750hp I believe.
 

Grant808

Active Member
Established Member
Joined
Jul 29, 2008
Messages
1,043
Location
Honolulu -> SoCal
N/A...6 speed
Blower...4R70W

But even N/A and the 4R70W should work well with a tall gear to match your expected trap speed and the right converter to get you going.
 

kevinp

Active Member
Established Member
Joined
Jun 23, 2010
Messages
1,054
Location
East TN
Cant really compare what gears people are using, The 6R80 has a 4.17 1st so you dont need a 4.10 like a 4R70. Plus 2nd gear is pretty much split in half on a 6R80 compared to a 4R70, you have 4 gears before you get near 1:1. That helps more with a stock converter to keep the RPM up..

Problem with the 6R80 is you cant shift it yourself, very expensive to fix and limited on converter choices. If good ETs are your goal a torque converter can make or break the whole thing, its the converters job to keep the RPM where it should be.

Myself I would do the 4R70, add a brake if you are going to be really racing and not just T&T and you are done. Dont get me wrong, I like the 6R80, but thats because its there :) Nothing lasts forever, I always rebuild my own autos and just looking at parts costs these 6R80s wont be cheap to fix/rebuild..
 

D1coyote

New Member
Established Member
Joined
Dec 29, 2011
Messages
113
Location
Alabama
I have my 6R80, stock converter, stock trans cooler w/ cooler lines and Circle D billet converter for sale on Modular Fords. Check it out if you are still interested. User name on Mod Fords is gdyup.

Well I have been thinking... I have my 86 mustang I just got done with putting the 2011 5.0 in and I went with a built T56 that I had done with all D&D Performance parts. I am starting to consider going auto for the best 1/4 mile times. Im getting aggrivated with the stick because of clutch pedal issues and other little things. Plus running a stick at the track a lot tends to be a little brutal on everything else. I priced a 2011 6 speed auto and $5000.00 without converter is nuts! not to mention the wiring and computer tuning would be pricey. So with that said I have been looking at manual valve body 4r70w w/transbrake and tc lock up. My only concern is the gear ratios in the transmission are no where near as good as the the 2011 6 speed auto. I just wonder if the car is gonna feel slow with the 4r70w. I know these cars perform really well with the new auto but its probably only because it keeps it way up in the rpms the whole time. I've been reading on the termi cobra forums where people go to the 4r70 but the are most of the time a turbo car with tons of torque. Main thing is I dont want to slow the car down... I need opinions!
 

DickieFord

New Member
Established Member
Joined
Mar 22, 2012
Messages
29
Location
Gulfport,ms
Well I have been thinking... I have my 86 mustang I just got done with putting the 2011 5.0 in and I went with a built T56 that I had done with all D&D Performance parts. I am starting to consider going auto for the best 1/4 mile times. Im getting aggrivated with the stick because of clutch pedal issues and other little things. Plus running a stick at the track a lot tends to be a little brutal on everything else. I priced a 2011 6 speed auto and $5000.00 without converter is nuts! not to mention the wiring and computer tuning would be pricey. So with that said I have been looking at manual valve body 4r70w w/transbrake and tc lock up. My only concern is the gear ratios in the transmission are no where near as good as the the 2011 6 speed auto. I just wonder if the car is gonna feel slow with the 4r70w. I know these cars perform really well with the new auto but its probably only because it keeps it way up in the rpms the whole time. I've been reading on the termi cobra forums where people go to the 4r70 but the are most of the time a turbo car with tons of torque. Main thing is I dont want to slow the car down... I need opinions!


hey man, I think i know you

well I just bought a lentech VB with trans brake, Im about to install it this week and i will let you know how i like it. I would just do the 4r75w It works really good in my car, I run a ptc custom stall also.
 

fatal1

Member
Established Member
Joined
Jul 20, 2004
Messages
206
Location
Jonesboro AR
Bringing this back from the dead, what did you decide to do? I found a deal on a 5.0 with 6r80 and all harnesses and whatever else I need. Curious if it would even fit without a bunch of modification. I'm a pretty good fabricator. I would like to try the 6r80 if its possible.
Thanks
 

5.0_KenneB

New Member
Established Member
Joined
Jun 9, 2012
Messages
261
Location
Tennessee
Th400 with a manual valve body!!!! Cheap and strong!! I'm actually putting th400 in mine right now for the trans with it rebuilt for 1000hp, converter, and oil cooler and all the others odds and ends stuff right now I'm at a little over 2k.
 

Users who are viewing this thread



Top