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6.4 392 Hemi/8 speed trans swap into 69 Charger

Colby

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Hey guys, I'm new to this forum and I'm sure the answer to my questions are out there somewhere in the forum.

I have a 69 Charger. It has a '66 440 with a 4 speed trans. I'm thinking about doing a 6.4 392 Hemi/8 speed trans swap.
  1. Some of the threads mentioned the trans tunnel would need to be reshaped, would that be the case for a 69 Charger and is there a different trans cross member that I would need to buy?
  2. Would I be able to bolt my 4 speed trans and bellhousing up to the 6.4 engine block?
  3. Are there certain years of the 6.4 that are better to use than others?
  4. Is there a book or list out there that details out what is involved in doing a saw like this?
  5. Is there a place that sells swap kit that comes with everything that is needed?
 
Greetings.....I only know that the bellhousing on the small block is the same pattern as the new hemi's bolt pattern. You would need to figure out input shaft length and assess how to tackle the bearing on the crank side. The Tunnel will need to be reshaped, as that trans is alot larger than the original automatic. Others will chime in that know a lot more on this, but those are the tid bits I can offer. If you do use an old style automatic on the newer hemi, you will need to buy the conversion flex plate that has the teeth on it for the starter, as the original style flex plates had no teeth on them and had the teeth on the convertor itself.
 
The conversion cars that I have were done before much was available. I your going with the automatic, yes the tunnel will have to be fabricated as well as the crossmember. Transmission will also need something done, because you will have to have a slip yoke for the driveshaft. As mentioned a small block bell housing will work on the engine, but input shaft length will have to be measured and taken into consideration when doing this as well as the clutch arrangement. Chrysler can say plug and play, but any conversion is going to require custom work to get everything functioning correctly.
One of cars uses a TKO 5-speed and has a small block bell housing, adapter plate, and changed to a hydraulic clutch. This transmission fits, but is extremely tight. The crossmember still has to be fabricated.
The other car had the Gen III engine and a reworked small block 727. It also requires an adapter plate, so the torque converter is in proper position.
 
Look at Hotwire for info on the 8 speed trans and Us Cartool for the crossmember and trans tunnel it can be done if you have a fat wallet. Bouchillon performance also a good source.
 
I'm doing a 5.7 8hp70 swap in a 1969 Coronet right now. The engine swap isn't that bad. They make a lot of the stuff for it especially for our cars. You'll need some type of engine control system. I'm going to alter the factory harness following information on diyhemi.com. You'll need a mid sump oil pan like the Milodon setup. For exhaust you are looking at either SRT Jeep manifolds or headers from TTI. Then of course the engine mounts. I bought the ones from TTI. It seems straight forward. The transmission however is NOT!

The tunnel needs raised a good 3 inches. The torsion bar cross member needs cut as well. The mount needs to have the transmission sitting lower. I emailed US Cartool and they said they should have some ready to ship around mid April. The mount will probably be around $300. If that falls through I'll fab my own. That's just what it takes to fit it in the car. You still have to connect it.

The transmission runs on input signals from the wheel speed sensors and various other sensors in modern cars. You will need some type of transmission control setup. I purchased the one from Sound German automotive for $1000.

These transmissions have a flange on the back of them. You will need to convert that to a yoke somehow to get a driveshaft connected. I'm using the one from Sonnax. Part no T35-ALFY-08. It's about $200 from summit. Then I'll have to get a drive shaft made with a slip joint in it. I'm told that will be a couple hundred more. I am connecting this to an 8 3/4 rear.

You'll also need a shifter. I want to keep my bench seat and I actually really like the dial shifter so I'll be purchasing one of those and mounting it in the dash. They can typically be had used for about $60.

It's not cheap but I'm building mine as a daily driver and it's worth it to me.
 
I'm looking to do a similar swap for my 65 Coronet. I would like to get a wrecked Hellcat and just swap everything over. (engine trans-wiring harness). I want the 8 speed trans. It seem the only issue is the rear axle tone rings that give signals to the 8 speed. I plan to machine a steel ring and put it on the 8-3/4 output yoke (in place of the dust shield). then put one tone ring on it. I will fabricate a bracket to mount the 2 sensors using the pinion snubbed bolt holes. This should eliminate the need for a special trans controller. Does this sound right?
 
FYI, the 8spd is 9" tall back at the rear mount. It's a very different shape than a 727.
 
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