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Wanting to swap four speed for c-4 help!!!!

  • Thread starter Thread starter krallman
  • Start date Start date Jan 13, 2007
K

krallman

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Mar 3, 2006
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Hurricane, WV
Jan 13, 2007
#1
  • Jan 13, 2007
  • #1
Okay im wanting to swap in a c-4 into 66 289. It has the 6 bolt bell housing pattern. Can i use a 70's and later model c-4 with a special torque converter. I was thinking about getting one from summit but it has the 26 spline input shaft. If so where can i get the torque converter. Also what bellhousing will i need. Or would it just be better to find a c-4 from a 65-69. I have looked for info a long while on this and any help would be appreciated.
 

SHIFTY101EASY

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Feb 24, 2006
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Jan 13, 2007
#2
  • Jan 13, 2007
  • #2
not to rain on your parade or anything...but your crazy to swap a manual for an auto....especially a 4 spd. top loader for a run of the mill C4......not only the time and effort, but i'd say your probably effectively lowering the value of your car doing that...and probably performance....but i guess to each his own
 

1965stangcoupe

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Sep 7, 2006
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Mount Vernon Washington
Jan 13, 2007
#3
  • Jan 13, 2007
  • #3
I'll take the pedals off your hands! have been looking for them for my swap to a t-5! But I agree why switch to a auto? oh well its your car. I do have a c4 but it came with my car and has been out of it for five years so I dont know if it needs a rebuild or what. good luck!
 
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D.Hearne

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Sep 29, 2000
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south louisiana
Jan 14, 2007
#4
  • Jan 14, 2007
  • #4
SHIFTY101EASY said:
not to rain on your parade or anything...but your crazy to swap a manual for an auto....especially a 4 spd. top loader for a run of the mill C4......not only the time and effort, but i'd say your probably effectively lowering the value of your car doing that...and probably performance....but i guess to each his own
Click to expand...

I whole heartedly agree. Even if the 4 speed was a Borg Warner T10 (these were used in many of the earlier Stangs) and not a Toploader, I still would never trade performance and (more importantly) durability for an automatic, much less a C-4. You also might need to swap the front yoke of the driveshaft for a 28 spline if the 4 speed had a 25 spline output. On the input of C-4's Ford switched from a 24 spline to a 26 in 1970. The C-4 you'll want will be a "case fill" C-4, these have a smaller bell that uses a 157 tooth flexplate. The "pan fill" C-4 was a heavier duty transmission that also used a larger torque converter and 164 tooth flexplate
 

DarkoStoj

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Sep 4, 2002
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Detroit
Jan 22, 2007
#5
  • Jan 22, 2007
  • #5
i got a complete 65 with c4 and everything you would need to switch over. Let me konw if you want to swap
 

ratio411

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Apr 21, 2002
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Pensacola FL
Jan 22, 2007
#6
  • Jan 22, 2007
  • #6
If you do the swap, make sure you just push your clutch pedal to the floor and maybe tuck it under the carpet. Keep all the linkage, tranny, and parts so you have it to put back later. The more you keep, the more of the value of the car you keep.
The later, early 70s C4s are a little stronger.
Stick with the case fill type though.
The pan fill tranny is what they call a C5 and was never used in a car.
It was a truck only tranny and uses a larger bell and such.
You are going to make more work for yourself going that route because the bell and relocated tube take up more room. Also has a larger, as in deeper, pan.
The tranny crossmember and driveshaft should swap fine. Always have for me.
You may need to replace the speedo cable. The C4 cable goes into the opposite side of the tranny compared to the Toploader.
Good luck
Dave

Edit: You will have to replace your starter!
The C4 uses the same starter, only the nose is a slight bit longer.
 

ratio411

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Apr 21, 2002
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Jan 22, 2007
#7
  • Jan 22, 2007
  • #7
If you are around WV, I know where a FREE 71 C4 is.

http://mmb.maverick.to/showthread.php?p=296970#post296970
 

Z06killinSBF

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Apr 25, 2005
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McKinney, TX
Jan 22, 2007
#8
  • Jan 22, 2007
  • #8
I have everything you could ask for to do a C-4 swap. I have a GER ProStreet manual/auto valve body, an 1800 stall and a 2200 stall converters, B&M ProStick, new starter, driveshaft, flexplate, motor plate, cross member, EVERYTHING. And I'll swap it for you 4 speed set-up.
 

Jsprint68

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Sep 10, 2003
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NJ
Jan 22, 2007
#9
  • Jan 22, 2007
  • #9
ratio411 said:
The later, early 70s C4s are a little stronger.
Click to expand...
 

Ogre

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Sep 24, 2003
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NC
Jan 22, 2007
#10
  • Jan 22, 2007
  • #10
Can someone shed some light on "case filled" and "pan filled" C-4s. I am thinking that the case filled C-4 has the dipstick tube that goes into the case and a pan filled tube goes in to the pan. I have a C-4 and the dipstick tube goes right down towards the pan. Is mine a pan filled then? The tube does go into the tranny case right above where the pan mounts underneath. I think it came out of a 75 Mustang with a 302.
 
D

D.Hearne

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Jan 23, 2007
#11
  • Jan 23, 2007
  • #11
You've got a case fill if it goes into the case. Pan fill goes directly into the pan. If yours was from a 75 Stang II, then it would be the unique, 147 tooth bellhousing model. These only came in the Mustang II's w/a V8. The bellhousing is much smaller than the others.
 
K

krallman

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Mar 3, 2006
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Hurricane, WV
Jan 23, 2007
#12
  • Jan 23, 2007
  • #12
well the car started off as a six cylinder with a c-4. so its completely opposite of what it was, but to tell you the truth it is all gonna go in my 85'. I am wanting to put an auto in there because im gonna be racing circle track, but i might just stick with the four speed. I dont think i have ever seen a fox with a 289 and a 4speed. I dont think it should be too hard. But, Then the 302 is gonna get built along with a t-5 and go back into the 65'.
 
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GNN60GT500

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Jun 18, 2002
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5 car lengths in front of you!
Jan 23, 2007
#13
  • Jan 23, 2007
  • #13
Now it makes sense-

Your putting a 5 speed back in the classic-


OK heart beat going down-

That would be crazy to switch a 4 speed to an auto-
 
F

fast4cheap

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Jan 22, 2007
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north carolina
Jan 23, 2007
#14
  • Jan 23, 2007
  • #14
its all the same

Either c-4 will work as long as you match the right year converter to the trans c-4 came in either pan or case fill, pan fill is more common to larger automobiles,the only difference in a c-4 and c-5 is the c-5 used a lockup style converter and had different valving in the valve body, a smaller 157 tooth bellhousing would leave more room,they also require a smaller bolt pattern on the torque converter,bolt spacing is 10inches or so on smaller 157 bellhousings and 11 and quater inches on the 164,this is the only thing you really have to worry about, and dont worry a c-4 is plenty tuff and the internals are light enough where performance will not really suffer.
 
D

D.Hearne

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south louisiana
Jan 23, 2007
#15
  • Jan 23, 2007
  • #15
Y'all are confusing the C-5's here. There were actually two different C-5's. One is the 80's Lockup version, the other, the 70's "Heavy Duty" C-4, I've also seen it refrred to somewhere as the C-5.
 
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