Help convince me to go BB in my Duster?

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So, I have a '74 Duster, who through a friend of a friend, can get a pretty solid 318, which would get built to 300-350, which would of been fine, but now I think it wouldn't be as enjoyable, or I'd always want faster?

I was looking into a 440 swap but everyone I know is telling me that it won't work, too much fabrication, front end will sag. Also is this too adventurous for a first-time motor swap? (i'd probably try to find one one CL that comes with trans, motor, msd, etc etc)

What all do I need for going BB?

I know through just common sense, I would need at least an 8 1/4 rear end, and from watching that one episode of Roadkill, I know I'll have some problems with the headers.

Is there a lot of fabrication into bracing the front end? Or would it just be heavy duty torsion bars? Do I need to mess with the trans tunnel?

My checklist so far (regardless of BB or SB):
- Schumacher Motor Mounts
- Heavy Duty Torsion Bars
- 8 1/4 rear end
- Some fabrication for the Headers
- MSD or some other ecu?
- disc brake conversion


Thanks for the help guys!
 
I was looking into a 440 swap but everyone I know is telling me that it won't work, too much fabrication, front end will sag. Also is this too adventurous for a first-time motor swap? (i'd probably try to find one one CL that comes with trans, motor, msd, etc et
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People you are talking to are idiots.

A big block is a bolt in deal. Biggest decision will be in the header dept.

I'd go with a .920 torsion bar if it's mainly a street car.

I know you can build big cube small blocks and all and a small block is lighter but there is nothing like a big block abody.
 
Convince you? Naaaa, you'll do it because you want it and the extra ceiling of power available to the engine, not to mention the cool looks, comments and on lookers asking the questions your happy to answer to increase there awe.

You don't need to be convince. Your already on the diving board! Dive in, the water is GREAT!

Fabrication is almost a zero. Schmaucher (sp?) mounts, headers/exhaust, wire shortening/lengthening, driveshaft shortening & probably a radiator size increase. OH! And a rear end swap. Do your springs at the same time.

Sagging front? NOPE! My /6 bars are fine.
Headers a pain? What else is new? I used Hedman "B" body headers. Instructions in the tech section of Big Block Dart .com.

Go for it and don't let anyone tell you it can't be done.
 
abodyjoe said:
People you are talking to are idiots.

A big block is a bolt in deal. Biggest decision will be in the header dept.

I'd go with a .920 torsion bar if it's mainly a street car.

I know you can build big cube small blocks and all and a small block is lighter but there is nothing like a big block abody.
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Haha, is it still a bolt in if the car is a /6 auto-tragic? I'd be trying to swap to BB/autotragic.

Is the "'73 & Up A,B,C,F,M,J-Body S6 to B/RB Conversion Kit" all i would need in terms of mounting it? Do I need tranny mounts?

rumblefish360 said:
Convince you? Naaaa, you'll do it because you want it and the extra ceiling of power available to the engine, not to mention the cool looks, comments and on lookers asking the questions your happy to answer to increase there awe.

You don't need to be convince. Your already on the diving board! Dive in, the water is GREAT!

Fabrication is almost a zero.
Click to expand...

This is really reassuring, how much (depending on what I can get the 440/trans for) can this swap be done for? I found some running 440/trans for $600 - 800, mounts and headers will also be around $600, can this realistically be done for under 3-4k?
 
I used the scumacher kit and headers. PSRT 1.03 torsion bars and my 8 1/4 is holding up. I just blew my tranny though, so beef it up.
 
halifaxhops said:
I used the scumacher kit and headers. PSRT 1.03 torsion bars and my 8 1/4 is holding up. I just blew my tranny though, so beef it up.
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What trans was it? Was your 440 modified? Were you racing / beating on it? I'd be running a 727, with a close to stock 440.
 
One of the many reasons I like the BB option is that you can build more power than is milder mannered and more reliable.

Again, it's a bolt in deal. Only fab work is getting the driveshaft cut.
 
Moded 440, prob 450hp. I used a 727 that I picked up and changed the valve body and 2200 stall. Yes I was beating on it hard to check out the carb mods. Let the line locks off and it shredded the trans! LOL
 
For you a 8 1/4 rear should be fine with a stock 440. Mine is holding up as a one wheel peel and 3.23 gears. I have a track loc with 3.55 that will go in over the winter.
 
Whats the best set up in the engine bay for it?

Power steering/Manual brakes? or vice versa? Can I run my stock K-Frame?

halifaxhops said:
For you a 8 1/4 rear should be fine with a stock 440. Mine is holding up as a one wheel peel and 3.23 gears. I have a track loc with 3.55 that will go in over the winter.
Click to expand...

Oops, just realized I've been saying 8 3/4, I did mean 8 1/4 haha
 
I have the /6 k frame, the trans just fit, ps/ and pb. Some people have problems with the valve cover hitting the blower motor but I used a low cover and have about 1/4" clearance. I will find a few pics. I still have the colum shift and had to mess with the z bar a bit, cut it down about 1/2". It is in a 74 dart se 4 door. Frame connectors are a good thing with all the torque.
 
here are some
 

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You will need a new radiator also. I got one off e bay for 250 and works fine so far. And the summit 2.5 exhaust is great for around 250
 
Hoppy, I would ixnay that air filter. If for some reason you should get a backfire that foam in the can melt and get sucked in.
 
Only thing that fit so far. I am molding a hood with two pop up scoops on either side so it looks stock until I hit it. Then it will go by bye! Trying to make it look like an old mans car.
 
Here
 

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Great, thanks for the help everyone! Hopefully sometime this winter season I can come back and say I now have a 440 duster!
 
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