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Early B Body Gen 3 HEMI swap. Who has done it?

Kustombuilder

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Hello everyone. I have been searching off and on for several weeks trying to find any information that I can on swapping a GEN 3 HEMI into a 63 Belvedere. Holley and several other companies make pretty much everything for this swap on a 66 and newer B body, but absolutely nothing is listed for the earlier B bodies (except for an oil pan). Can anyone shed some light on why that is? What is different? What problems might we run into? We are by no means inexperienced in this field, but I'd like to know what obstacles we might encounter before we dive head first into uncharted water.

Thank you for any help or information that you can share.
 
Don't do it. Just ruins another perfect classic car. However, it is your car you can do what you want to it.
My buddy wants to do this very same thing to his 63 Sport Fury. I told him, I am not helping.... lol. i think classic cars should be left classic.
 
We have a forum about it. I just moved this thread there. New Hemi engine swaps. Read till your eyes bleed.
 
Hello everyone. I have been searching off and on for several weeks trying to find any information that I can on swapping a GEN 3 HEMI into a 63 Belvedere. Holley and several other companies make pretty much everything for this swap on a 66 and newer B body, but absolutely nothing is listed for the earlier B bodies (except for an oil pan). Can anyone shed some light on why that is? What is different? What problems might we run into? We are by no means inexperienced in this field, but I'd like to know what obstacles we might encounter before we dive head first into uncharted water.

Thank you for any help or information that you can share.
I am in the slow process of building a 65 coronet convertible with a gen III hemi. I am doing it because I want a road trip car that is dependable and fuel efficient. Granted I like preserving the classics, my car is a plain jane 440 trim that had a 273, no air and no options but power steering. If I would fix it up stock it would not turn many heads. But do the hemi right and it will turn a lot of heads plus be much more enjoyable. Having done some conversions, my experience is they all require lots of fabrication, I have the tools and experience to do that. If you don't have a well-equipped shop and wanting to do something basically bolt together not only, is it more expensive it may be problematic if parts are not available. The main thing I can stress is taking the time to fix all the little bugs that will crop up to make it a smooth running and driving vehicle. The other thing is especially in the wiring use connectors and solder connections, so the harness is durable and can be removed for service. For example, many aftermarket wiring harnesses don't come with a bulkhead connector. I usually dry assemble the vehicle and then take it back apart to paint, how do you do that if you have a bundle of wires going through the firewall with no way to unhook them?
 
We have a forum about it. I just moved this thread there. New Hemi engine swaps. Read till your eyes bleed.
My eyes ARE bleeding and my back sore from sitting in front of this screen. I haven't found any useful information (on the early B bodies) yet.
 
Use the search function and type in….

late model Hemi into early b body

That’s my thread for a Gen 3 Hemi into my 64 Polara 500.
 
I am in the slow process of building a 65 coronet convertible with a gen III hemi. I am doing it because I want a road trip car that is dependable and fuel efficient. Granted I like preserving the classics, my car is a plain jane 440 trim that had a 273, no air and no options but power steering. If I would fix it up stock it would not turn many heads. But do the hemi right and it will turn a lot of heads plus be much more enjoyable. Having done some conversions, my experience is they all require lots of fabrication, I have the tools and experience to do that. If you don't have a well-equipped shop and wanting to do something basically bolt together not only, is it more expensive it may be problematic if parts are not available. The main thing I can stress is taking the time to fix all the little bugs that will crop up to make it a smooth running and driving vehicle. The other thing is especially in the wiring use connectors and solder connections, so the harness is durable and can be removed for service. For example, many aftermarket wiring harnesses don't come with a bulkhead connector. I usually dry assemble the vehicle and then take it back apart to paint, how do you do that if you have a bundle of wires going through the firewall with no way to unhook them?
All very good advice. We actually do own and operate a well equipped hot rod shop outside of Detroit. We've done a lot of late model swaps in all sorts of classic vehicles, but this is our first Gen 3 HEMI in an early B body. I'm quite familiar with what needs to be done in a later 66-72 B body HEMI swap, but not being very familiar with the earlier B bodies, and how they differ from the later ones leaves me with a lot of questions. I'm not one to start a project like this without doing my homework first. Especially when it's someone else's money, since this is a customer car. That is also why it makes more sense to use as many aftermarket parts as possible. We could fabricate anything and everything necessary, but I can't build a one-off set of motor mounts, or fabricate a custom set of headers for less than someone could buy mass produced units from an aftermarket supplier. We're all about giving our customers the best quality work at the lowest price possible. That doesn't mean it will be cheap, but if we can save them a few hundred here and a few hundred there by using proven aftermarket parts, rather than making them, then we will.
 
Use the search function and type in….

late model Hemi into early b body

That’s my thread for a Gen 3 Hemi into my 64 Polara 500.
I did exactly that and got a million completely unrelated posts. But thank you for the heads up. I'll look for your post specifically.
 
I found it for ya!

 
Use the search function and type in….

late model Hemi into early b body

That’s my thread for a Gen 3 Hemi into my 64 Polara 500.
I copied and pasted "late model Hemi into early b body" and the only things coming up are the dozen or so times you pointed someone to your post, but the post itself is not coming up. Could you possibly share a link?
 
Gen III conversion is a great deal, especially with a modern trans to get all the spread-out ratios. A 6.4 with headers and a air-filter change, will get you over 500hp. A little tuning will get even more. Great doing 2K at 85mph and getting mid 20's mpg.....with A/C.
There are plenty of old cars around, so I'd do as I liked.
 
Gen III conversion is a great deal, especially with a modern trans to get all the spread-out ratios. A 6.4 with headers and a air-filter change, will get you over 500hp. A little tuning will get even more. Great doing 2K at 85mph and getting mid 20's mpg.....with A/C.
There are plenty of old cars around, so I'd do as I liked.
Love the Orwell quote... I'm aware of all of the advantages of this swap. Do you happen to have any personal experience with a conversion of this nature in an early (65 and older) B-body?
 
I haven't done the swap, but the difference in years is the early cars have the drivetrain further ahead in the car, about 1 1/2-2". And I believe the tunnel is subsequently a bit smaller. It's the same k member, but with different mounts moved further ahead. I can only assume, the motor mounts aren't made.
But at the same time, you'll be fabricating a trans mount anyway, so you can adjust the drivetrain in the car however it fits best. Possibility of header clearance issues at the steering box as well
 
I haven't done the swap, but the difference in years is the early cars have the drivetrain further ahead in the car, about 1 1/2-2". And I believe the tunnel is subsequently a bit smaller. It's the same k member, but with different mounts moved further ahead. I can only assume, the motor mounts aren't made.
But at the same time, you'll be fabricating a trans mount anyway, so you can adjust the drivetrain in the car however it fits best. Possibility of header clearance issues at the steering box as well
I'm worried about trans tunnel clearance. It is a beautiful car with a finished interior. Really don't want to start cutting the floor up and building a new tunnel.
Holley makes headers, motors mounts, trans mounts and even a full exhaust that all fits very well in the later B bodies. It would be great if we could use all of that stuff on this car. A lot cheaper for our customer to buy parts than for us to make one-off units.
Based on some of my reading I am wondering if putting the newer K-member into the older car would make any difference? Like I said, the less parts we have to fabricate, the less hours the customer has to pay us. We like to look out for our customers, but we still have to get paid for our hours.
 
I'm worried about trans tunnel clearance. It is a beautiful car with a finished interior. Really don't want to start cutting the floor up and building a new tunnel.
Holley makes headers, motors mounts, trans mounts and even a full exhaust that all fits very well in the later B bodies. It would be great if we could use all of that stuff on this car. A lot cheaper for our customer to buy parts than for us to make one-off units.
Based on some of my reading I am wondering if putting the newer K-member into the older car would make any difference? Like I said, the less parts we have to fabricate, the less hours the customer has to pay us. We like to look out for our customers, but we still have to get paid for our hours.
To me, (assuming the 8sp is larger) there will have to be tunnel reconstruction.
The new k will only push it back and make it worse.
If the customer wants unobtainium, then it costs unobtainium dollars?
 
To me, (assuming the 8sp is larger) there will have to be tunnel reconstruction.
The new k will only push it back and make it worse.
If the customer wants unobtainium, then it costs unobtainium dollars?
It is larger than the 727 currently in the car. The 8HP70 fits in the 66 and up B bodies with a little minor trimming to some of the bosses on the transmission case (nothing structural). Only minor trimming of the floor brace above the transmission tail housing is necessary. I'd like know conclusively that it will fit the early cars just as well. Or to know conclusively that it won't, so that I can pursue other options. We are problem solvers after all. I'm just trying to flesh out as many problems as possible before the build begins. This ensures a smoother process once the build starts and keeps me from having a half assembled project cluttering up the shop while we sort through the inevitable problems on the fly. We are known for getting projects done quickly and with a high level of quality, and that is due to proper research and planning. It is something we are quite proud of.
 
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