1970 C4 advice

Hi,
I recently purchased a 1970 maverick with the 170 i6 and auto c4. When purchased I thought I just needed a flex plate. After pulling the trans I learned that the torque converter has a ring gear welded around it. I located one for $250 rebuilt. More than I was planning for this part but not horrible if it meant getting it back on the road. I dropped the transmission pan and found a lot of "grit" that I will upload a picture of.
Question is, is the only way to move forward/is it worth it by rebuilding this trans and buying TC? From what I've read I can get a later C4 and use my current bell housing but I'd still have to purchase the TC or can I also convert to a TC/flexplate?
My plan was to get it on the road and enjoy it with current drivetrain and later on upgrade to either a bigger 6 or small block v8, which is why I'm asking now is it cost effective to put so much into this setup.
Thanks for any advice!
Keaton
 

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bubba22349

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Hi,
I recently purchased a 1970 maverick with the 170 i6 and auto c4. When purchased I thought I just needed a flex plate. After pulling the trans I learned that the torque converter has a ring gear welded around it. I located one for $250 rebuilt. More than I was planning for this part but not horrible if it meant getting it back on the road. I dropped the transmission pan and found a lot of "grit" that I will upload a picture of.
Question is, is the only way to move forward/is it worth it by rebuilding this trans and buying TC? From what I've read I can get a later C4 and use my current bell housing but I'd still have to purchase the TC or can I also convert to a TC/flexplate?
My plan was to get it on the road and enjoy it with current drivetrain and later on upgrade to either a bigger 6 or small block v8, which is why I'm asking now is it cost effective to put so much into this setup.
Thanks for any advice!
Keaton
Hi Keaton, yes you are correct that you could get another C4 and than just bolt it up by using the current 170 / 200 Six Bell Housing as long as the next C4 is also a Case Fill Trans like you have now. Be warned that there are also some bigger C4's that are of the Pan Fill type used in Trucks and Bigger Ford Cars those they will not bolt up with your Bell Housing the case is very different so its best to stay away from them.

As long as you stay with the Smaller Sixes (I.E. a 144, 170, or 200 Six) you can not use the 250 Six or V8 type Flex Plate or their TC with the small bolt pattern Bell Housings used on the Smaller Sixes. If you go looking for another Trans the 1971 to 1982 SBF V8 C4 is in my OPIN the best ones to find and use for most any Performance use they all ready have all of the Ford Factory improvements like the larger and stronger input shafts with 26 Splines on both ends and so there are more Stock and Performance Parts available for them (they will use the same TC number that you have right now since its also the Larger 26 Spline Input Shaft on the Torque Convertor end) also they will have the extra Clutch's and Steel's that a 4 or Six cylinder C4 Trans is missing. The 1970 Trans also a very good but it a one year only Trans and has a strange Input Shaft with different Spline counts 26 on TC end and 24 on the Front Drum End so there is not much aftermarket parts support.

The 1970 C4 is really a decent Trans to use if you want to rebuild it you could do most all of the other factory upgrades of what the later C4 V8 Transmissions will have this is because of the 1970 up share the style Trans Case that can't be changed but it is still a very good one as is I just put in one of the 40-2 TransGo Shift Kits in them and add a small Hayden or other accessory Trans Cooler. You could also easily add a 1972 up V8 Front and Rear Drum to get the extra Clutches and also get the Larger Diameter Input Shaft in the same process then it would handle a built up Big Six or a SBF V8 too. By the way if you look hard you should be able to find a rebuilt TC for a small 170 or 200 six with the Ring Gear for about $150.00 plus Refundable Core charge with an exchange. There are also Street Performance TC available for the small Six at about $500.00 plus core gives you about a 400 to 500 RPM Stall increase. Hope that is helpful for you, good luck. Edited
 
Thanks a lot for the advice, I really appreciate it.
Do you have a lead on a place to get a torque converter or a recommendation on the search? Ive stumbled on a place in Washington for $250 but never heard back from them when I asked to confirm it would fit. A local place has one for 250 I might pull the trigger on or have mine rebuilt just double the commuting time.
Again I appreciate your time
Keaton
 

bubba22349

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Hi Keaton, I have been working on finding Performance parts for an older 1965 C4 lately and had seen a stock Torque Convertor (TC) for the 1964 to 1969 C4's for $148.00 plus core, I though that I had saved the link. I did find the other one for the later model C4's like yours with a 26 Spine Count TC. Its a little more at $185.00 and you would sure want to send them your TC Core to save the $150.00 core charge but with your core its going be a little lower price than those $250.00 ones you found, here's the link for it. One other way you can go if you think the TC is still in good working order is that some Transmission shop have a TC Cleaner to flush them out I don't know how well that works as I have always went with a Rebuilt for a freshly rebuilt Trans.

https://www.ebay.com/itm/172730864756?_trkparms=amclksrc=ITM&aid=1110006&algo=HOMESPLICE.SIM&ao=1&asc=20200818143230&meid=02693863fb7f4e6fba1e9aa592d97a73&pid=101224&rk=5&rkt=5&sd=252570227483&itm=172730864756&pmt=0&noa=1&pg=2047675&algv=DefaultOrganicWeb&brand=TC&_trksid=p2047675.c101224.m-1#vi-desc-maincntr

I also wanted let you know that I made a couple mistakes on the years of the parts for the C4's that your 1970 Trans would use in my above post so I have corrected them just now. I was off by one year and yours is a very good one about as good as any of the later C4's plus it has the Bigger input shaft already. The Dividing Line for the Better C4's is the 1970 and up and the two older versions are the 1964 to 1966 Duel Range C4's and then the next group was a major improvement with the debut of the 1967 to 1969 "Select Shift" C4's. Best of luck
 
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