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C4 Torque converter

Blasto

New Member
Joined
Sep 17, 2023
Messages
5
I bought a used 1974 c4 that came out of a bronco, I had it rebuilt and the problem I have is I need a torque converter. I have searched all my local automotive stores and had no luck. Where can I get one? And is there a generic or different one that is not listed for a bronco? Please help. My motor is a 302.
 

jeffncs

Contributor
Bronco Guru
Joined
May 4, 2004
Messages
1,894
Loc.
Raleigh, NC
I’ve been there don’t that and about to take same ride again. Local store options are super limited. They may be able to special order one but you’ll either have to order one through a atranmission oarts supplier(local or online) or have to send yours off for rebuild.

Whatever you do, don’t throw a used t/c into a newly built trans. All the garbage that you can’t clean oit will just rush into your clean trans and could have real downside impacts.
 

DirtDonk

Contributor
Bronco Guru
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Nov 3, 2003
Messages
51,618
And make sure to measure your bolt pattern before you order anything.
While the’74 “should” be just the on size, there were two different ones used over the years and many will get it wrong.
And getting the wrong one is not a simple fix. While you can buy torque converters in both patterns, you can’t currently buy flex plates in both patterns. So if you get the wrong torque converter, you can’t necessarily just go out and buy a new flex plate to match.
 

Bajabrewer

Contributor
Bronco Guru
Joined
Jan 28, 2012
Messages
1,673
I went thru this a few years ago & ended up getting a Bully Dog for my C4 & it's been working great. Somewhere along the way I found that Precision of New Hampton(PNH) rebuilds the convertors for Bully Dog(and others) so If I were to get another I would go right to PNH. If you don't see what you want or need in the list there is a phone # at the top of the page.

Hope this helps get the one you need.

https://gopnh.com/Ford-Transmissions/C4
 
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Blasto

New Member
Joined
Sep 17, 2023
Messages
5
My big problem is I have a new crate motor and I bought a 74 bronco transmission I just had rebuilt, but it didn't come with the torque converter. It's pan fill with flared case. I was looking at the bm converters on the Holly site and they say do not use a 10.5 in a flared case. So I guess I need to find a 11.5 and a 164 tooth flex plate does this sound correct?
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
51,618
The 164t part is always correct for a Bronco. As long as whatever bell-housing (or integrated into the trans, as in this case) is designed for the trucks.
Do you know without a doubt what imbalance factor was used for your new engine? A "crate motor" is simply a brand new engine, but that means that very likely it is a 50oz imbalance, where the original engine in any Early Bronco was a 28oz imbalance.
If it's a stroker type engine however, it could also be a "zero" imbalance, due to it being internally balanced instead.

If it does not say anywhere in your paperwork, can you contact the seller to verify?
Is it a standard 302/5.0 with carburetor? Did they say what imbalance factor it is?

Not exactly sure what they mean by not using a "10.5" converter. Is that a bolt-pattern thing? Or an actual size thing? Sounds similar to the bolt-patterns, but since Ford utilized both sizes on Broncos over the years, I'm not making sense of their wording.
 
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Blasto

New Member
Joined
Sep 17, 2023
Messages
5
The crate motor I bought was for a 74 bronco, the listing on power train says 75 to 79 302/5.0. I will have to call them to find out if it's a 28 or 50 oz
 
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Blasto

New Member
Joined
Sep 17, 2023
Messages
5
I just looked at the number on the new motor and it was D20E which is a 72 go figure I ordered fo a 74.
 

DirtDonk

Contributor
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Joined
Nov 3, 2003
Messages
51,618
That’s normal. You won’t always have an engineering number matching your year.
It’s not like they changed the engine every year enough to change the part number. So whatever upgrades that got in 72 to make the difference, probably lasted through at least a couple of years.

And unless you’re paying tens of thousands of dollars for accurate date matching engines for a restoration. No company in their right mind is going to drill down that deep into the numbering system to make sure everybody gets something super accurate. So a 72 engineered block could still be legit for you.
While it’s out though (is it out?) look for the casting date. Down near the starter.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
51,618
But in theory, at least, it should be a 28 ounce motor. However, since any engine builder can easily change that to a 50, you are definitely better off calling them.
Now is the time to be sure, rather than later.
 

Master Chief

Contributor
Bronco Guru
Joined
Nov 24, 2006
Messages
1,311
Once you figure out what you have for a flexplate, I highly recommend ACC Performance. for a torque converter. Complete their form (http://www.accperformance.com/services.html) and email them. In case you have never weighed your Bronco, my 1/2 cab is roughly 3750 lbs on the scale at the local scrap yard.


Toll Free: (888) 267-7464)
Local: (256) 381-1965
Email: techline@accperformance.com

ACC Performance Products Plus
BOSS HOG™ Torque Converters
2817 Avalon Avenue
Muscle Shoals, AL 35661
 
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