Install 392 (Gen 1)Hemi

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STR-14

STR-14

I put the hoar in hoarder
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I've researched this site and found a couple of useful comments, but no real details. Has anybody got any direct info on installing a 392 Chrysler hemi into an A body? I have the info from MoParts, but finer details are lacking. I'm curious mostly about fitment. I've seen a few installs here and there on other sites, but no fine details. Clearly it will take some fabrication skills and some pre-planning. Some of my questions are more like what is being used for exhaust (what actually works), how is the clearance for the transmission tunnel, what are the best transmission options (there are a lot), starter options, engine mounting (biggie), and rad clearance. In short, what works best. I'm considering an install in a '70 Dart and don't want to re-invent the wheel. I suspect this is going to be not so simple or even cheap. Thanks in advance for any advice.
 
It isn't cheap at all but it's been made pretty easy since it's become so common. The 392 is the same as the 5.7 for the most part, so just look to see what the 5.7 guys are using. There are headers, mounts, etc for the setup.

What are you planning on doing for an engine management system? Do you have the stock stuff or are you going aftermarket?

There are adapters to put 727s and 833s behind a gen 3 hemi.

It's all a pretty common swap these days and that 392 won't be any easier or harder than a 345 or 370.
 
Or maybe you're talking about an early hemi, in which case I look like an asshole.

In that case I'm useless.
 
Nope, you're not an asshole, but all your questions are why I'm not doing a Gen 3. I'm not so good with that type of wiring and fuel systems management. Some guys on here are absolute geniuses when it come to electronics, etc - me, not so much.
 
If I'm not mistaken the 392 is wider than the 426.
I have never done the 392 swap in an A body for any
real help or tips but I would say your suspicions of it not being simple are correct.
I would start with a width measurement of the 392
at its widest point across the valve covers compared to the available space in your A body. I believe the steering colume will be your biggest interference.
 
The transmission bell housing pattern is the same as the small block with the exception that the dowels are in different locations, so the transmission tunnel should require little to no modification. There are a couple of members who've done the swap. Maybe they will chime in.

Also, I would lose the 392 heads. They are inferior to the 54 and up 331 and 354 heads. The intake ports are much longer and curve downward in the port floor. Rather than cast different intakes to make up the difference with the tall deck 392, Chrysler made the heads wider at the intake ports.

By installing the 392 size valves in the 331 or 354 heads, you end up with a much better flowing head. This of course does not include the 51-53 small round exhaust port 331 heads. They are doorstops.
 
There's a member here on FABO who installed a Gen I 354 Hemi in a 65 Valiant. Your 70 Dart is wider in the engine compartment so it should be somewhat easier. IIRC the 62-66 poly engine mounts will bolt to the early Hemi and should bolt to the 70 K Frame.
 
Run some massive torsion bars as that motor is heavy.
 
I looked into putting a 354 Hemi into our 67 Barracuda. I decided to go with a Desoto 341 Hemi instead. Same mounting ears and spacing as a small block Chrysler. The mounting ears are farther apart on the Chrysler Early Hemi's. The Early Hemi's are not as heavy as everyone likes to say they are. After talking to people who had actually done the swap, the 392 and 354 and 331 will fit, maybe a nip and tuck with the inner fender wells. Usually they drop the K frame an inch or two, and make custom mounts. Headers and exhaust are custom of course. Hot Heads (Hot Heads Research & Racing Early Chrysler Hemi Home) are a source for Aluminum heads, updated front ends, oil pumps and distributor adapters, transmission adapters, as well as general rebuilding parts. Early Hemi's are expensive but they are good for about 1,000 horsepower, especially the 392, out of the box. Just add a Supercharger.
 
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