400 into 65 valiant

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Moremopars4ed

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I don’t see much info about big blocks in older a-bodys. I’m going to attempt it. Anyone else? What do I need to look out for?
/6 about to come out. Have the trans Dapt motor mounts for 67 and up anticipating some fab work, going to see if the stock truck manifolds might work. Otherwise I think the Schumacher tri-y headers should work? Everything the sell is for 67 and up. Thanks
 
It won’t fit with as produced parts from anybody. To put the RB in mine I’m having to:
Notch the K frame.
Fab mounts for the engine and transmission.
Modify the trans cross member.
Modify the trans tunnel on the floor.
Modify the left side inner fender steel to allow more room for headers.
Fabricate headers.

other than that it’s bolt in... lol
 
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It won’t fit with as produced parts from anybody. To put the RB in mine I’m having to:
Notch the K frame.
Fab mounts for the engine and transmission.
Modify the trans cross member.
Modify the trans tunnel on the floor.
Modify the left side inner fender steel to allow more room for headers.
Fabricate headers.

other than that it’s bolt in... lol
you are using automatic ? I was hoping the stock trans mount/ location would at least work. Things lined up fairly easy in my 67 dart. The k frame looks tiny in these things

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I should clarify- im using the ‘65 only big block 727 and the stock floor cable shift, and my goal was to have a taller intake with nitrous plate under the flat hood. Plus there’s some other tricks being built into it. But all that being said- a big block doesn’t fit easily- at least not in ready to run form. Mounts are the easy part. Floor, trans mount, and exhaust are the sticky spots.
 
I was looking on my phone for the pictures but I did mock up a couple years ago. If you search the forums on early a big blocks there’s stuff around on them.
The ‘67 was designed to allow a big block. The early a never was. So with torsions bars and full inner fenders it’s tight. Plus the floor and trans crossmember are not designed for dual exhaust. So if you want bigger pipes you will need to address that too, or leave the right side pipe lower.
 
You manifolds are out. And I’m not sure which pan you have, but the smaller the sump and more central it is, the better. The performance pans have the volume added to the front of the pan. That will hit the K frame without some serious cutting.
 
streetmaster used to (may still have) custom motor mounts for this. I have a set for a future project. i understand that a B will fit with 68-70 HP ex manifolds. Trim the sloped firewall junction protrusion & wouldn't hurt to weld that now flat joint across for strength. also a good plan is to modify the crossmember so you can run dual ex without the one side pipe hanging too low. I ran a 727 with a SB in an early A & the trans just touched the sloped firewall protruding pinch weld joint & I under stand tolerances varied alot & some may clear & some need work. I have a bell to adapt a big block to a 904 which will elim the firewall issues tho the 904 will have to be build up more to handle the BB. this is all the info I've come up with for my way in the future build
 
I think the B manifolds fit the 67-up “later A”. I’ve done that before. I do not believe they will work in the early a although my experiments were with the RB it wasn’t even close where that shorter deck provided the room.
 
streetmaster used to (may still have) custom motor mounts for this. I have a set for a future project. i understand that a B will fit with 68-70 HP ex manifolds. Trim the sloped firewall junction protrusion & wouldn't hurt to weld that now flat joint across for strength. also a good plan is to modify the crossmember so you can run dual ex without the one side pipe hanging too low. I ran a 727 with a SB in an early A & the trans just touched the sloped firewall protruding pinch weld joint & I under stand tolerances varied alot & some may clear & some need work. I have a bell to adapt a big block to a 904 which will elim the firewall issues tho the 904 will have to be build up more to handle the BB. this is all the info I've come up with for my way in the future build
Thanks for the info! Do you have a picture of those motor mounts?
 
My racing buddy has all my stuff in his storage & he just got the virus so it might be awhile. I will post em on this forum when I can get to em. RR
 
easy bolt in deal but not with 67-up parts. i didn't notch the k-frame and didn't modify the crossmember. used an off the shelf chrome oil pan and moroso valve covers cleared the master cyl and blower motor perfectly.. someone used to sell the proper mounts for the swap.. not sure if they still do. no one makes headers for them which is the biggest issue.. to me its not even worth doing if you are choking it down with manifolds.. and schumacher tri y's aren't fitting in there if you can even find a pair.

440 in my old 64.

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That's the way; unhunh, unhunh
Had fenderwells on a 340 in a 65 V100,back in early 70s.
I remember they were extremely expensive compared to the run of the mill $80 headers. Oh man, that was like 47 years ago!, daymn I'm getting old.....
 
That's the way; unhunh, unhunh
Had fenderwells on a 340 in a 65 V100,back in early 70s.
I remember they were extremely expensive compared to the run of the mill $80 headers. Oh man, that was like 47 years ago!, daymn I'm getting old.....

the custom made headers weren't cheap in the early 90's either..:)
 
i put an rb/727 in a 65 dart, /6 trans mount and tunnel were fine. just needed to flatten the tunnel/bulkhead lip. big cutout on the k member for the sump which wasn't the one most use, just a normal pass' car one. i made fenderwell headers and my own mounts. sorry about the old crappy pic'.
neil.

dartful bodger.JPG
 
Found a couple mock-up pictures. Goal as I said was a tall intake, carb, and plate, with a good air cleaner, under the flat hood. Also with custom made under-chassis headers. This picture shows the RH inner fender in stock form. It's been modified now to allow for more pipe clearance as all the steel work is done.

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