Technical 429 c6 swap from T18 I broke sumpin

Remove the T 18 four-speed granny gear out of the back of a 429, 1968 for 29, old and C6 up to it broken in the ears and the bell housing because the talking burner snout is too deep. So, is this a normal thing to not have a torque converter from a C6 460 fit the back of a 429?

yes I removed the pilot bushing first, but didn’t dry for the converter to the flex plate…. Oops

 

Here’s the converter from the 460

 

Was the converter engaged all the way?
Did you have the converter drain plug in the correct location with the flex plate?

 

This flex plate offers for drain plug openings at each one, so it doesn’t matter where it’s clocked and I did hold it up and it stops right as the threads reach the holes. The snout on this 460 converter is too long. 1984 c6 I believe

 

Yeah, I think that is a later model converter. You need one that is not tapered. Probably same as like a 390, 427,428. I don’t remember the size.

 

Thank you!

 

My crank

 

Is part of the pilot bearing still in there? Can’t really tell. Take the converter and put it up against there and see if it fits.

 

I physically lifted the torque converter up and indexed it two different times even though it’s not necessary because every bolt hole has a pilot hole next to it for the converter drain. And it stops flush with the holes because the snout is hitting inside or at least it seems to be.

 

Here’s my plate

 

The center hole on my crank is 1.241 inches and my snout definitely touches it.

 

There are two different pilot torque converters.
Later models has a much longer smaller od.
Early models had a much shorter larger od.
Early only goes in the outer register in the crank.

You have the later model converter and early crank.

Bill

 

So a simple early converter from day a 73 mustang with a 429 will suffice?

 

Converter needs to be
31 spline
1.848 pilot

Probably a little older than 1973, those were transition years

Go to:
Precision of New Hampton, look up C6. They list all the different converters with photos.

gopnh.com

Bill

 

Thank you bill. My parts guy has a factory 1800 stall converter for 116 bucks plus 18 bucks shipping….. I’m kinda shocked at that price. Online they’re 300-500 bucks

 

Just make sure it has the correct pilot 1.848 dia

 

The center hole in my crank is one point whatever the hell I set up there in the other post a 1.8 is not gonna fit it

 

1.4 across center of hole….

 

There are only two different pilot diameters
1.375" diameter, overall length longer
1.848" diameter, overall length shorter

You need to clean up the back of that crank, it looks like something is still in there from the photo.

Bill

 

Oh OK the 1.8 is the diameter not the depth that makes sense now and it’s all metal. There’s nothing in there except some grease from a previous pilot bearing and yes it will be cleaned out tomorrow.

 

One more question. Could this flex plate be incorrect?
There’s a counterweight welded in, and I was****uming the 429/460 was internally balanced. This is about 3/4” wide by (iirc without removing it) 3” long in a curved shape.
Is this simply to balance the flex plate or a likely improper one for this application?

 

Later engines were externally balanced. (counter weight) Remove the counter weight.

 

This engine is a 68 429. It’s not a whole lot later. The flex plate is from a 94 460.

I’m going to clock it to the flywheel I removed from the 429, mark it, then do a bubble balance test and see if the flywheel has the same balance.

this swap is frustrating because I’m finding it very difficult to font the short snout c6 converter which is pre 73.

 

You’re also missing the flex plate ring. Keeps the flex plate from getting stress cracks around the bolt holes.

 

I didn’t notice that but I also noticed that there is no impression or markings from a previous flex plate ring on this 42,000 mile RV transmission

 

Best I can recall , small block depth is different than big block depth . This could be the issue .

 

There’s no small block anything going on here. Going 68 429 4speed to C6. All c6 after 73 have a longer pilot snout, it hits the crank before the converter bolts can be tightened. 1/2 too deep. Older converters larger diameter snout shallower depth. This is a 94 c6