318\a904 swap in 65 barracuda

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Kody meile

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hi everyone, just curious what it takes to swap in an la318 and an a904 in a 65 barracuda, car car has a slant 6, I know it will need different motor mounts and I already had a driveshaft made for the car with a slip yoke. will probably need a new tunnel shift and a cables too right? for the trans? also are there any aftermarket early abody small block headers available? all advice will be appreciated thanks
 
You’ll need the V8 center link too. Used ones show for sale here and I believe someone is making repops now too.
 
You’ll need the V8 center link too. Used ones show for sale here and I believe someone is making repops now too.
thanks! anything else I should know about? I mean I don't think theres a lot to do but just curious..
 
When Upgrading to the power from a V8, You might consider upgrading your front brakes. The 9 inch slant front brakes were woefully inadequate when new; with modern cars and their disc brakes being able to stop on a dime and give you 9c change, even more so today
 
I’m guessing you also had the dual cable transmission shift linkage previously. If you end up with a 66+ trans, you’ll have to update your shifter too. Mine was a column shift so I eventually being looking for 66 column or maybe go with a universal aftermarket.
 
Not there yet, but will be modifying my cable shift for my later type 904. cant be that difficult.
 
I’m guessing you also had the dual cable transmission shift linkage previously. If you end up with a 66+ trans, you’ll have to update your shifter too. Mine was a column shift so I eventually being looking for 66 column or maybe go with a universal aftermarket.
I don't have that setup anymore, I was going to just put one of those b&m shifters and cables in, tbh I hate the early duel cable ball\trunnion stuff its just straight junk in my opinion..
 
When Upgrading to the power from a V8, You might consider upgrading your front brakes. The 9 inch slant front brakes were woefully inadequate when new; with modern cars and their disc brakes being able to stop on a dime and give you 9c change, even more so today
I have my drum brakes pretty dialed in on the car for now, probably do a bbp disk brake swap down the road..
 
I have my drum brakes pretty dialed in on the car for now, probably do a bbp disk brake swap down the road..
Well if that's true, and your brakes are 9", you better leave the slanty in there. Or leave the 318/904 car in the driveway.
65Dartman was being tactful and kind when he said woefully inadequate.
Those 9inchers are good to 30 mph, in a straight line, with the slanty. The 318 will accelerate probably 4 times as fast, and will be up to the speed limit right smartly, and when you find yourself running up some guys tailpipe, those 9s will not slow you down fast enough. Plus when going into a corner just a little too hot, I have busted the ends right off the spindles, and watched the tire roll across 4 lanes of traffic.
Maybe you'll be luckier.
Maybe not.
Wear a helmet and install a 5-point harness.And keep a seatbelt cutter handy.
Or just keep it under 30 mph; and in a straight line.
 
Well if that's true, and your brakes are 9", you better leave the slanty in there. Or leave the 318/904 car in the driveway.
65Dartman was being tactful and kind when he said woefully inadequate.
Those 9inchers are good to 30 mph, in a straight line, with the slanty. The 318 will accelerate probably 4 times as fast, and will be up to the speed limit right smartly, and when you find yourself running up some guys tailpipe, those 9s will not slow you down fast enough. Plus when going into a corner just a little too hot, I have busted the ends right off the spindles, and watched the tire roll across 4 lanes of traffic.
Maybe you'll be luckier.
Maybe not.
Wear a helmet and install a 5-point harness.And keep a seatbelt cutter handy.
Or just keep it under 30 mph; and in a straight line.
they are the 9 inchers, to be honest the car wont be a racecar or anything but im not going to go around racing the thing, car probably wont see the road for alteast another year anyways..
 
Okay, LOTS of threads on this; search function is your friend. That being said, here's the basics:
ENGINE & TRANS
If you've got the D150 that you're pulling it out of, pull EVERYTHING you can; ie throttle cable, kickdown linkages, ignition and charging system wiring and modules, trans linkages and cooling lines, motor mounts and brackets, solenoids and battery cables, ground straps, the works... you may not end up using it all, but the way these projects go, more often than not you'll be glad you've got it. Don't forget to grab the driveshaft too, you might be able to get it cut down to fit your car; if not, you'll still at least need the transmission yoke.
Parts you'll need to source elsewhere: Passenger car oil pan & pump pickup, early A throttle pedal and cable (although you might be able to adapt the truck ones), and a '70-'76 A body 24" smallblock radiator and shroud and matching fan.
You'll need motor mounts and engine brackets for an early A V8. Or, depending on your abilities and creativity, build your own or modify the truck units to work.
You didn't say if you've got power steering or not; if you do, most truck power steering will hit the early A k frame. You can either source passcar brackets or shorten and redrill the truck brackets (about 1 1/4 in. if memory serves). I prefer to mod the truck brackets, that way I can still use all the original pulleys.
You also need a plan for your exhaust- if you have power steering, you basically have one choice: the early A smallblock manifolds. BUT BEWARE! With your '87 motor, you have air injection ports below the exhaust ports that need to be plugged (search the thread under smallblock motors). After you do that, you'll find that the extended pad beneath the #7 port prevents the manifold from properly seating. A little judicious grinding with a Dremel USUALLY takes care of it, but go SLOWLY! If you take too much, or core shift is really bad, you run the risk of breaking into a coolant passage, and you've got a junk head on your hands (go ahead, ask me how I know...). At a minimum, you'll need the driver's side manifold- the truck manifold can work on the passenger side.
If you have manual steering, that opens up a LOT of other options beside the early A manifolds: ANY standard A manifolds of any year (318, 340, 360), the 340 HP manifolds, or Ram/Dakota magnum manifolds, among others. All these options seem to require cutting back the collar on the steering column (again, use Search to get the whole story) and a little grinding on the manifolds for column clearance. And again, test fit the manifolds- some of these options also require grinding the heads for proper fitment as above.
If you want headers, it's Doug's, TTI, modded shorties (search), Spitfire fenderwell exits, or build your own.
On your trans, some of the truck 904s had cast-in reinforcement ribs that interfere with the extremely narrow transmission tunnel and crossmember in early As. You will have to grind these down to get it to fit.
Your year trans MAY use a speed sensor- if so, it needs to be replaced with a standard cable drive. Use a '66 cable to hook it up to your speedometer.
Reuse the truck cooler lines if they're any good. Just cut to fit and reflare.
Shift linkage is up to you. Aftermarket floor shifter, swap in a '66 non-cable shift column and linkage, or some other column and cobble up the truck linkage to it.

BRAKES and SUSPENSION
As mentioned, 9" brakes ain't gonna cut it in 2020.
If you're really bucks down, at a minimum, you could swap on a set of 10" drums and spindles, lots of guys who have upgraded to discs have these laying around and you can score a good deal. Otherwise, search the braking threads on disc upgrades and pick your poison. Lots of choices out there.
One thing to consider: if that year D150 still has the 4.5" bolt circle, grab the rear drums and backing plates in case you ever upgrade to the large bolt pattern. You'll be glad you did, or you can resell or use for tradebait on something else.
Same goes for suspension. At a minimum get some V8 T-bars in there and some good shocks. New rear leaves have gotten pretty affordable of late, it's not worth messing with saggy 55 year old units. Use Search and pick a vendor.
You may or may not need a different steering center link for the V8. Some slant 6 cars came with the V8 center link. Some guys have pulled off the swap without having to change theirs. Once the motor is in, see what you've got for clearance and make the call.
The rear end is dicey at best- non suregrip 7.25s like to grenade under raised power levels. Plan for a future upgrade. Some guys have lived with them for years, some guys never made it out of the driveway. Make your choice, take your chance.
As far as the driveshaft goes, one from a '66 Barracuda or Valiant
with a 904 should be a bolt in, if you can't find one, have the truck shaft shortened (provided it uses the right size U-joints for your rear). Have a new shaft made when you upgrade your rear.
ELECTRICAL
Use the truck harness to upgrade to electronic ignition and and better alternator and electronic voltage regulator. Search the electrical threads to find the modified wiring diagrams/schematics.

I'm sure I'm forgetting something, but this should be enough to get you started. Besides, my fingers are getting tired.
Tim
 
Last edited:
#1 just to put the engine in the car you need : engine brackets and rubber mounts because /6 are different . #2 you need a v-8 radiator and hoses because /6 are smaller . #3 . Next is a-body left side exhaust manifold , to get around steering . #4 . throttle cable and brackets . that isn't all but others have covered it pretty well . It's not a very difficult swap but it does take some planning . Good luck !
 
they are the 9 inchers, to be honest the car wont be a racecar or anything but im not going to go around racing the thing, car probably wont see the road for alteast another year anyways..
Going from a 225,if that's what you have;to a 318;You're gonna be nearly tripling the torque and doubling the power, at a minimum. So saying yur not gonna race it ............................. well, let's just say;power is addictive.
And anyway, like I said, when the wheel keeps on rolling, while yur car comes crashing down on the pavement, that is not a happy time. It usually takes out the fender on it's way out. And then you still have to pray your wheel doesn't take somebody else out too.
Look, I may not be the unluckiest guy in the world but I have only had three 9" set ups in over 50 years of driving, and only two of 'em broke a spindle. One I broke, and the other I bought broken, and both were slanty cars.
That is a failure rate of 2/6 or 33%. Both of the Barracudas were very low mileage; I acquired one in 77 just before I got married, and the other a year later.
I got lucky in that mine broke at UNDER 30 mph.Just driving down the road minding my own business. I slowed down for a corner, and mid turn, I got the surprise of my life. By the way, when a front drum is not there, the front brakes do not work. But it really doesn't matter that much, cuz the corner that goes down, does a lotta the braking for you.
 
One more thing I forgot to mention in my previous post: Take the stock single pot Master cylinder OFF THAT CAR!! New dual-reservoir units are dirt cheap on Rock Auto (or wherever), just match it to the braking system you're going to use. Losing your brakes (and possibly a lot more) because of having a single reservoir master is no better than AJ's story about losing the wheel...!
 
Okay, LOTS of threads on this; search function is your friend. That being said, here's the basics:
ENGINE & TRANS
If you've got the D150 that you're pulling it out of, pull EVERYTHING you can; ie throttle cable, kickdown linkages, ignition and charging system wiring and modules, trans linkages and cooling lines, motor mounts and brackets, solenoids and battery cables, ground straps, the works... you may not end up using it all, but the way these projects go, more often than not you'll be glad you've got it. Don't forget to grab the driveshaft too, you might be able to get it cut down to fit your car; if not, you'll still at least need the transmission yoke.
Parts you'll need to source elsewhere: Passenger car oil pan & pump pickup, early A throttle pedal and cable (although you might be able to adapt the truck ones), and a '70-'76 A body 24" smallblock radiator and shroud and matching fan.
You'll need motor mounts and engine brackets for an early A V8. Or, depending on your abilities and creativity, build your own or modify the truck units to work.
You didn't say if you've got power steering or not; if you do, most truck power steering will hit the early A k frame. You can either source passcar brackets or shorten and redrill the truck brackets (about 1 1/4 in. if memory serves). I prefer to mod the truck brackets, that way I can still use all the original pulleys.
You also need a plan for your exhaust- if you have power steering, you basically have one choice: the early A smallblock manifolds. BUT BEWARE! With your '87 motor, you have air injection ports below the exhaust ports that need to be plugged (search the thread under smallblock motors). After you do that, you'll find that the extended pad beneath the #7 port prevents the manifold from properly seating. A little judicious grinding with a Dremel USUALLY takes care of it, but go SLOWLY! If you take too much, or core shift is really bad, you run the risk of breaking into a coolant passage, and you've got a junk head on your hands (go ahead, ask me how I know...). At a minimum, you'll need the driver's side manifold- the truck manifold can work on the passenger side.
If you have manual steering, that opens up a LOT of other options beside the early A manifolds: ANY standard A manifolds of any year (318, 340, 360), the 340 HP manifolds, or Ram/Dakota magnum manifolds, among others. All these options seem to require cutting back the collar on the steering column (again, use Search to get the whole story) and a little grinding on the manifolds for column clearance. And again, test fit the manifolds- some of these options also require grinding the heads for proper fitment as above.
If you want headers, it's Doug's, TTI, modded shorties (search), Spitfire fenderwell exits, or build your own.
On your trans, some of the truck 904s had cast-in reinforcement ribs that interfere with the extremely narrow transmission tunnel and crossmember in early As. You will have to grind these down to get it to fit.
Your year trans MAY use a speed sensor- if so, it needs to be replaced with a standard cable drive. Use a '66 cable to hook it up to your speedometer.
Reuse the truck cooler lines if they're any good. Just cut to fit and reflare.
Shift linkage is up to you. Aftermarket floor shifter, swap in a '66 non-cable shift column and linkage, or some other column and cobble up the truck linkage to it.

BRAKES and SUSPENSION
As mentioned, 9" brakes ain't gonna cut it in 2020.
If you're really bucks down, at a minimum, you could swap on a set of 10" drums and spindles, lots of guys who have upgraded to discs have these laying around and you can score a good deal. Otherwise, search the braking threads on disc upgrades and pick your poison. Lots of choices out there.
One thing to consider: if that year D150 still has the 4.5" bolt circle, grab the rear drums and backing plates in case you ever upgrade to the large bolt pattern. You'll be glad you did, or you can resell or use for tradebait on something else.
Same goes for suspension. At a minimum get some V8 T-bars in there and some good shocks. New rear leaves have gotten pretty affordable of late, it's not worth messing with saggy 55 year old units. Use Search and pick a vendor.
You may or may not need a different steering center link for the V8. Some slant 6 cars came with the V8 center link. Some guys have pulled off the swap without having to change theirs. Once the motor is in, see what you've got for clearance and make the call.
The rear end is dicey at best- non suregrip 7.25s like to grenade under raised power levels. Plan for a future upgrade. Some guys have lived with them for years, some guys never made it out of the driveway. Make your choice, take your chance.
As far as the driveshaft goes, one from a '66 Barracuda or Valiant
with a 904 should be a bolt in, if you can't find one, have the truck shaft shortened (provided it uses the right size U-joints for your rear). Have a new shaft made when you upgrade your rear.
ELECTRICAL
Use the truck harness to upgrade to electronic ignition and and better alternator and electronic voltage regulator. Search the electrical threads to find the modified wiring diagrams/schematics.

I'm sure I'm forgetting something, but this should be enough to get you started. Besides, my fingers are getting tired.
Tim
All bases are covered here. Awesome write up.
One tidbit to add, driveshaft can be shortened, and at rear a conversion u-joint can be installed to mate truck u-joint to 7.25 rear end. I have done it.
 
ill probably post more about it when I actually start doing the swap, thanks everyone for your input
 
One more thing I forgot to mention in my previous post: Take the stock single pot Master cylinder OFF THAT CAR!! New dual-reservoir units are dirt cheap on Rock Auto (or wherever), just match it to the braking system you're going to use. Losing your brakes (and possibly a lot more) because of having a single reservoir master is no better than AJ's story about losing the wheel...!

Double, no triple amen to this! Had all four brakes go out on a 66 Belvedere once while driving in DC. Not fun. Busted one stop light and one stop sign before I could get it stopped. Had 5 others in the car with me. All was good in the end but I got lucky.
 
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