small block to big block

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73 Shwinger

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I have a 73 Dart with a 360 in it....what will it take to mount a 440 in it's place??
 
Many posts on this, use the Search. Need special motor mounts, different transmission, driveshaft, maybe a different rear end, maybe an aluminum radiator, stiffer torsion bars if a street driver. Headers often need a cutout in the fender wells. If not, the exhaust is choked so much the BB doesn't make much more power than a SB. The result is hard to handle on the street and most people do it to make a drag racing only car.
 
BillGrissom said:
Many posts on this, use the Search. Need special motor mounts, different transmission, driveshaft, maybe a different rear end, maybe an aluminum radiator, stiffer torsion bars if a street driver. Headers often need a cutout in the fender wells. If not, the exhaust is choked so much the BB doesn't make much more power than a SB. The result is hard to handle on the street and most people do it to make a drag racing only car.
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Yikes! well maybe that helped me a bunch sounds like i am building my small block lol......all that extra money for the swap willl be that much more goodies for the sb! thanks for your help / advise Bill! :prayer:
 
It sounds like a lot, but in the end, its costs about the same *IF* youre starting from scratch.
 
BillGrissom said:
Many posts on this, use the Search. Need special motor mounts, different transmission, driveshaft, maybe a different rear end, maybe an aluminum radiator, stiffer torsion bars if a street driver. Headers often need a cutout in the fender wells. If not, the exhaust is choked so much the BB doesn't make much more power than a SB. The result is hard to handle on the street and most people do it to make a drag racing only car.
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it's expensive, but if you get a bolt in front end (hemidenny makes them, or you can buy alterkation from rms) it will handle BETTER than originally, particularly if you build the BB with aluminum heads/intake.

the BB will weigh as much at that point as a stock SB, and the torsion bars are long gone (more weight gone) and you will have a modern suspension.

you will need a big block 727 auto trans or a big block bellhousing/manual trans

as far as power you can bet the BB will attain higher HP levels easier than SB (there is no replacement for displacement)

yes you can built the chit out of a SB, but BB heads flow more and you can put a lot more cubes in a BB (up to 572c.i.). you can get even get 500 to 600HP out of a BB without a stroker kit

so it's actually cheaper to get 500HP or more out of a big block than with a small block in the long run.
 
Spend some time in the tech pages at Big Block Dart, especially:

http://www.bigblockdart.com/techpages/dck.shtml

In my opinion, every suspension/brake mod the car might need, it needs it for any performance build (being a 73 V8 car it should already have discs and possibly a sway bar). So, in the end the biggest expense will be in new exhaust if you go BB.
 
The swap is not as bad as it sounds. Go to Schumacher creative services and get the swap kit with the instrutions for your car. A little trimming and drilling on the K-frame and it will drop in. You can keep the small block torsion bars if you want. The front end will bush more on the turns if you take them fast. For the strip they will work fine. Yes you will need another driveshaft only if you change the rear axle or your 360 has a 904 trans. You can keep the rear axle you have for now if its a 7 1/4, but I would make plans to change to a 8 1/4 or 8 3/4. With the Schumacher headers my 440 make 500 Hp on the dyno and you do not have to cut the fender wells.
 
is it easier to install it from the bottom then the top..i meant bolt it to the k and lower the car down on it????? i am asking as if it is i may just go ahead and paint my dart...but if not i waill wait and paint after the motor is installed in the car..:D

sorry for the hi jack ..i am doing the same swap 6 to big block in 73 dart
 
The hemi guys tend to lower the car down on to the k-frame, so i don't see why you couldn't with a B/RB too.

I'm just going to drop mine in from above (on my '74 Scamp), I've got a '68 440 Mag / 727 short tail combo to cram in that car (with A/C, Power Steering & Power Brakes)

My biggest challenges will be getting the Mickey Thompson valve covers to clear the brake booster & blower motor. And of course the thing every B/RB A-body owner dreads.... tune ups :finga:
 
Dropping the car over the drivetrain is a good way to go. I've done it both ways, but it is always easier with the steering column removed, whether you're coming in from the bottom or top.

Don't automatically choose Schumacher mounts for a 73-76 V8 k-member. Building your own DC k-member is fairly simple and doesn't cost much. Then you can use factory mounts. This is the way I have gone on every big block a-body we have built, plus I've probably built 30-40 k-members for other folks.
 
Schumacher mounts are the way to go, they are made to fit for these engine swaps. You can trim for oil pump clearance and driill for the mounts and drop the motor in place with in an hour. No cutting off old mounts and moving them to reweld. Plus you can always go back to a small block if you get tired of the big block with out cutting and welding.
 
On a 73-76 small block k-member to big block Schumacher kit you CANNOT go back if you decide to. That kit requires shortening the driver side motor mount saddle. Spend your money on Schumacher if you want to. I'll save that money for other parts.
 
Jim Lusk said:
On a 73-76 small block k-member to big block Schumacher kit you CANNOT go back if you decide to. That kit requires shortening the driver side motor mount saddle. Spend your money on Schumacher if you want to. I'll save that money for other parts.
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When you go back, you just weld the piece back on. Its better then trying to move both mounts back to there original position the way you do it. There is nothing wrong with the way you do it. It is just easier to install a big block with Schumacher mounts, even when you decide to change it back to a small block on the 73 -up. On the 68-72 A-bodies, just change the motors mounts and your down. Now for only $160, Schumacher mounts is the way I will always go.
 
Easier is in where you define it. It's easier on my wallet to pay $20 for a k-member and $10 for mounts (maybe a little more now with inflation) and a little more for weld wire and cutoff wheels. That's where I ALWAYS look for easier, on my finances......... Plus, building a DC k-member doesn't take that much time. I'm still pulling the k-member for a dip in my hot tank so that's the same amount of work.
 
BillGrissom said:
Many posts on this, use the Search. Need special motor mounts, different transmission, driveshaft, maybe a different rear end, maybe an aluminum radiator, stiffer torsion bars if a street driver. Headers often need a cutout in the fender wells. If not, the exhaust is choked so much the BB doesn't make much more power than a SB. The result is hard to handle on the street and most people do it to make a drag racing only car.
Click to expand...

I have under chassis headers(CPPA) so no cutouts in the fenderwells. With Hellwig frt and rear sway bars my car handles on the street just fine, that's all it sees! Just make sure you point it straight before:burnout:
Don't be afraid....big block A-bodies are a complete hoot to drive!!
 
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