700R4 in a 1974 C3
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Joined: Dec 2001
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From: Manitouwadge Ontario
700R4 in a 1974 C3
I have acquired a 700R4. I have seen many posts where cars in the 74 range have had these installed. What are the advantages over the TH400 I have now, numbers matching? The TH400 has 96000 miles on it and leaks fluid everywhere and needs to be rebuilt.
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Joined: Apr 2001
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From: Regina Saskatchewan, Canada.
Re: 700R4 in a 1974 C3 (Tired74)
Your obvious advantages are the fact that a 700-R4 has .70 overdrive and a lockup converter. The 3.06 first gear is cool too, but the rpm drop to second gear is not that great. The TH400's are pretty much bullet proof when built right but because all the internals and such are so big and heavy the transmissions tend to rob alot of horsepower. A 700 won't be at such a loss. But because they weren't meant for high amounts of torque to begin with they must be built to last which can cost a bit of cash. Stall convertors for the 700 can get close to $1000 US dollars. I haven't regreted mine though in the couple years i've had it. I just wish the gear spacing was better.
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From: Atlanta Georiga
Re: 700R4 in a 1974 C3 (Stingy74)
Your obvious advantages are the fact that a 700-R4 has .70 overdrive and a lockup converter. The 3.06 first gear is cool too, but the rpm drop to second gear is not that great. The TH400's are pretty much bullet proof when built right but because all the internals and such are so big and heavy the transmissions tend to rob alot of horsepower. A 700 won't be at such a loss. But because they weren't meant for high amounts of torque to begin with they must be built to last which can cost a bit of cash. Stall convertors for the 700 can get close to $1000 US dollars. I haven't regreted mine though in the couple years i've had it. I just wish the gear spacing was better.
(I'm sure they're be more opinions on this one... I've read it many-a-times around here)
Brian
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Joined: Aug 2000
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From: Montrose CA
Re: 700R4 in a 1974 C3 (Brian-74-454)
You say you already have the 700 so you're already in for the long haul... I selected the 200 R4 from Bowtie Overdrives because of the following reasons... lower overdrive ratio 0.67 vs. 0.70, the lower weight reputed to be 30-lbs less, but the ABSOLUTE NUMBER ONE REASON IS...... BOLT IN INSTALLATION! No screwing around with the drive shaft, the cross member, the cooling lines. Even the shifter linkage/starter shutout was a two-hour drill, hacksaw, and bolt install. The TV cable hooked directly to my Rochester carb kickdown cleate. The ease of installation sold me on the smaller tranny... what about power???? Bowtie says they warranty 200's running behind 502 ci engines - thats good enough for me.
Persons on this forum say changing the tranny to an overdrive model is the single most productive change you can make on a C3 - I gotta agree - My 70-mph rpm is about 1850 - now I can go somewhere instead of always thinking about my next fuel stop.
Persons on this forum say changing the tranny to an overdrive model is the single most productive change you can make on a C3 - I gotta agree - My 70-mph rpm is about 1850 - now I can go somewhere instead of always thinking about my next fuel stop.
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Joined: May 1999
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From: Mandeville, Louisiana
Re: 700R4 in a 1974 C3 (Tired74)
I am not as educated on mine as I should be...but I can tell you that 1st and 2nd are much higher gears than the TH400. So you will be quicker off the line. But then 3rd and 4th are pretty low for mileage, and of course then you can lock up the converter and just cruise at high speed while your engine just idles along...the 700R4 give my car a complete different personality than than any other C3 I know of in my club, both on trips, and at the track. You will like it!
