392 swap vs 340/416 build

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71duster06

71duster06

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Good evening all, up until recently I have been planning on upgrading my 340 4speed to a 416 stroker and aftermarket 5 or 6 speed transmission. With that said until recently...

I found a couple 392 Hemis with 6 speed for a relatively if not less cost than the 416 approach. I have not spent much time yet looking into this swap but I wanted to get everyone's thoughts on pros/cons.

Thanks all in advance!

Kyle
 
One huge advantage?
Smooth idle.
Another?
Double the fuel economy.
 
Start adding up fuel system, engine control, exhaust, cooling, and swap mounts, plus fab work. Other than the Passion 5 speed no 5 or 6 speed it s drop in, the tunnel will need to be opened up. I'd like to to do it someday but I need to get my first 340 going before I move on....
 
if your into doing / trouble shooting the electronics, cool.
 
It’s not cheap but you will be glad you did it! 392 with 6 speed

2A740A4B-9457-4B54-B228-608510C1F257.jpeg
 
Mine was roughly $4500 minus motor and trans. Probably closer to $5500 with all the little pieces I needed. Harness headers, fuel system, oil pan, cooling fan, radiator, gas pedal, shifter, drive shaft, gauges to name a few. I enjoy it a lot. I paid 2500 for my 5.7 and 545rfe trans. But that was in 2009. No problems after all these years. I drive it all the time. I’ve put around 60,000 miles on it. Oh and the big ticket was the Altekation suspension that is not included in that was another $4500. Open your wallet. That was 10 years ago
 
71duster06 said:
Million dollar question, based on what you experienced is the a general dollar amount your build came in at?
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I would say Logan is pretty close on dollar amount minus drivetrain. Of course it depends on what parts you use. I went with an aftermarket k-member which made it a lot easier but a lot more expensive.
 
69Dartguy said:
I would say Logan is pretty close on dollar amount minus drivetrain. Of course it depends on what parts you use. I went with an aftermarket k-member which made it a lot easier but a lot more expensive.
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Got it, it's nice to have that guage at least. I was around 11k for the 416 build and aftermarket transmission. I would like to keep it comparable "if" the 392 is a better all around rout . With these swaps getting more common I'm looking for a good thread that outlines the parts/steps needed to perform this swap.

Kyle
 
I have a question for you. Would that 11 grand get that 416 to a reliable, every day driven, no issue 485 plus horsepower? Actually, that question is directed at the naysayers that can't move out of the 60's. I grew up with the old school big blocks and small blocks. Have huge respect, that's what got me and kept me in the hobby. And now my livelyhood. Go with the Hemi, you'll be so glad you did.
 
I drive the hell out of my car. Everybody has told me the early hemis had valve problems (which there are a lot of). But I have had no problems with it since the first day I turned the key on it. It starts up every time. I have ran it at the track and auto cross race it. Every Sunday the wife and I go for about a 4 hour cruise (when the weather is under 85). No AC yet but in the process of installing it. Just waiting on the $75 dollar compressor adapters (which you will have to buy if you add AC. If you have the cash it’s well worth the time and energy spent.
Most guys around here can’t make car shows and cruises because their stuff won’t run half the time. I’ve done the Power Tour twice. Driven from San Antonio Tx to Las Vegas, San Francisco, Carlisle PA, and Louisiana-that’s my annual short trip to New Orlean it’s an 8 hour drive. Cruising at 80mph and if I need pass someone it’s like slicing butter with a hot knife.
 
If you have to ask then 392 Hemi and keep the SB Mopars for us who can't let go of the. :thumbsup:
 
408 swinger said:
I have a question for you. Would that 11 grand get that 416 to a reliable, every day driven, no issue 485 plus horsepower? Actually, that question is directed at the naysayers that can't move out of the 60's. I grew up with the old school big blocks and small blocks. Have huge respect, that's what got me and kept me in the hobby. And now my livelyhood. Go with the Hemi, you'll be so glad you did.
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You make an excellant point. My current 340 runs awesome but the more I modify, the more side effects show up as well regarding drivability and temperament. Since I'm 90% street and 10% track that has been one of my biggest concerns. I finally get the performance but at what cost.

I will begin looking more into the entire build process of the 392 hemi/6 speed route. Other than ebay, does anyone have reputable sources that sell modern powertrains like this? I'm all ears and looking forward to this build
 
71duster0 [QUOTE="71duster06 said:
You make an excellant point. My current 340 runs awesome but the more I modify, the more side effects show up as well regarding drivability and temperament. Since I'm 90% street and 10% track that has been one of my biggest concerns. I finally get the performance but at what cost.

I will begin looking more into the entire build process of the 392 hemi/6 speed route. Other than ebay, does anyone have reputable sources that sell modern powertrains like this? I'm all ears and looking forward to this build
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Cleveland Performance sells used setups. They come on a pallet so can put a battery and oil in the engine and start it up. They have all the accessories on them too. Some stuff you will use and a lot of stuff you won’t. I didn’t use the harness. I used A Hotwire Harness. Not sure what they cost now. I purchased mine 3 or 4 years ago.
 
if i were to do our dart over today it would no doubt have a modern hemi in it. i had most of the small block stuff laying around so thats the rout i went. in hind sight i should have just spent the money and went modern hemi.
 
loganscuda said:
You beat me to it I was looking for that thread to post on here. Pretty good price. I would put the 545rfe auto behind use 2005 ECM and Hotwire harness and be done. I like automatic trans. My knees are shot.
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Good to know. I still plan on the 6 speed while my knees still allow. :)
 
71duster06 said:
Good to know. I still plan on the 6 speed while my knees still allow. :)
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Trimec makes a floor/firewall kit for the swap in A bodies I saw it at Carlisle last year pretty neat setup. They may even make the transmission cross member. If no one makes it yet you will have to fab your own.
 
@Tjfly4pay makes a crossmember for the T56 that’s strong enough to allow you to run torsion bars, he has a thread here or you can PM him. It works great, and takes all the guesswork out of the fabrication. You just need to do the tunnel around the new crossmember. Then you just need engine mounts for the stock K and can knock a few grand off your total that you’d spend for the tubular K and coilovers. There are headers that fit with the torsion bars.

The hardest fabrication work is for the transmission, and the crossmember takes care of most of that. I love the T56 in my car. I have the T56 install in my build thread My "new" '74 Duster- or why I need a project like a hole in the head

CE9F2B09-3A15-480E-ABC3-C2336F4458D1.jpeg


I really enjoy the 340 as well, but I’m considering fuel injection going forward. And if I added up my costs between building my 340 and doing everything necessary for the fuel injection I wouldn’t be far off going to a Gen III Hemi. I spent over $6k building my 340, and have more money in it since then. It runs great and puts out a little over 400 hp, but for a daily driver it’s a little high strung. And gets 13mpg around town even with the 6 speed. Adding the cost of fuel injection to that and I know I could be under that total cost with a Gen III, especially if you leave the transmission out (like you would if you’re going T56 either way).

I like the simplicity of just having a 750 double pumper on the car, but, for a daily fuel injection will be so much nicer for drive-ability. And with FI you need a computer, so, if you’re already doing that the Gen III isn’t that much more computer junk.
 
What's wrong with a 360HO?
I had one iteration that spun 295s to well over 60 mph, broke the 295s loose at 45mph in second gear (m/t car),went 106 in the quarter and pulled down unbelievable fuel mileage. I drove that car for 4 years like that, then upsized the cam to the next bigger, and she went 93 in the Eighth.(The Wallace calculator translates that to 115 in the quarter,IIRC.)
I think that engine now has ~100,000 trouble-free miles on it.
If there was a road to China, and I had reason to go there, I would not be afraid to get on it.

Passing power? You want passing power?
I have pulled even with back bumper of a car going 60, slammed it into 3rd and was doing over 85 when eyeballing the other driver, lol. I love doing this! Yeah ok I concede that I need third gear with my 3.55s,lol.
 
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There's a guy on Facebook gen 3 hemi swap that has a Non MDS complete with clutch zero mile 392 for 6 thousand.
 
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