65 Valiant swap 273 to a 360

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Litz

Litz

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I have a chance to buy a 1974 360 and TF trans with 40,000 miles that was pulled from a motor home. The engine is pretty much a bolt in swap but aside from "Massaging" the firewall for clearance will the motor home trans work? Thanks for any replies, Litz
 
Not sure why you would have to massage the firewall?
 
There should be no need to "massage" the firewall for clearance - the 360 is the same outside dimensionally as the 273. Now the motor home transmission, that's another story. For starters I bet it's a 727 which means the pinch weld most likely will need to be flattened. The transmission might have the emergency brake on the tail shaft. A pic of the donor transmission would certainly help.
 
65 Dartman said:
There should be no need to "massage" the firewall for clearance - the 360 is the same outside dimensionally as the 273. Now the motor home transmission, that's another story. For starters I bet it's a 727 which means the pinch weld most likely will need to be flattened. The transmission might have the emergency brake on the tail shaft. A pic of the donor transmission would certainly help.
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Haven't bought the pkg. yet. My concern was the tailshaft length on the TF motorhome trans compaired to a car trans. I've been told that a truck/motorhome trans tailshaft is longer?
 
I suspect it will be B,E,C truck length on the tail shaft. Getting a pic will tell everything!
 
ken5124 said:
I am thinking a 727 will not fit.. I have a 65 valiant with a 904 and it is already snug
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The pinch weld will have to be flattened to make room for the 727. I would like to use my cable shifted 904 from the original 273 engine but I don't think the converter will work with the 360 crank?
 
abodyjoe said:
is it a shortie 727?

personally i'd find a car 904 and use that...
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I would like to us the cable shifted 904 that is behind the original 273 but I don't think the converter will work with the 360 crankshaft. Or if there would be any balance issues. I don't know much about the small blocks so forgive my ignorance. Thx for the reply, Litz
 
Pretty sure you can swap the pump to a newer pump and be able to use a more common converter.

Balance is as easy as just getting a b&m flexplate for a 360.
 
Litz said:
I would like to us the cable shifted 904 that is behind the original 273 but I don't think the converter will work with the 360 crankshaft. Or if there would be any balance issues. I don't know much about the small blocks so forgive my ignorance. Thx for the reply, Litz
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That would be cool but unfortunately you are correct the converter will not work. The early 904's had an 18 spline input shaft and the 67 or so ups had a 27 spline input shaft plus a larger torque converter snout diameter. Your push button also would have a zero balance converter and you will need a balanced one for your 360.
Still, you should be able to find a reputable shop to modify snout and balance your push button trans converter to mate up to a 360.
Of course it will cost $
Pat Blais transmission is a good source for early to late modification
206-365-1966
 
Pat Blais make an annular ring to take up the space so you can use your early converter with the 68 and up motors! You can also have one made by any machine shop, it's really just a spacer that slips in the register on the crank and the torque converter snout fits into! Not much to it really!!
 
cosgig said:
Pat Blais make an annular ring to take up the space so you can use your early converter with the 68 and up motors! You can also have one made by any machine shop, it's really just a spacer that slips in the register on the crank and the torque converter snout fits into! Not much to it really!!
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Wow! Thanks for the info! Like I said in an earlier post I'm new to the small blocks and still learning. (Thanks to guys like you) Thanks again
 
you also have modify the motor mounts, they are different on a 360. it's not that hard I did with washers and spacer and an extra bolt a nut.
 
So I bought the 74 motor home 360 and TF yesterday and am making a list for parts needed for the swap. I need a car oil pan, and pickup for sure but I'm not sure of what I can swap off the 273 onto the 360? I just replaced the fuel pump on the 273. Will that pump work with the 360? Also the timing chain cover will probably need to be swapped but I don't think the 273 cover will work with the 360? Any other help/advice would be appreciated.
 
Your 273 timing cover and water pump will be different and you're right about the oil pan thev360 is different anyway. Everything else should pretty much interchange except for mentioned TF and tq. If the 360 still has a distributor it will most likely be an electronic one, and again you could use th distributor off the 273 if you're still running points.
 
Valkman said:
Your 273 timing cover and water pump will be different and you're right about the oil pan thev360 is different anyway. Everything else should pretty much interchange except for mentioned TF and tq. If the 360 still has a distributor it will most likely be an electronic one, and again you could use th distributor off the 273 if you're still running points.
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Thanks for the info. Yeah I figured I'd use the 273 dist. until I do the electronic up-grade. Pat Blais makes an adapter ring that will enable me to use my 904 trans and converter using a B&M flexplate.
 
The inlet to water pump on the 360 is on the opposite side. If you wish to keep the 273 rad then you will need to swap the entire 273 front end onto the 360; EXCEPT the ballancer which is 360 specific. This means you will need to reindex the ballancer for #1 TDC. This is not a big deal.
But IMO moving the lower rad spigot is a better idea. Then you get to keep the better late-style water pump. If the power steering pump gets to be in the way, then you have two choices: get the late style pump mounts, or back to swapping the frontends. When you start swapping these parts around, you may find that various pulleys don't line up anymore. This is a PITA but it just means getting the matching right stuff.
Personally, I would, and did, change over to the 70up style front end. And just got a matching rad.

The funny thing is, I did this type of swap in about 1975. I put a 69 340 into a 65 V100Wagon(originally a slanty) and used a 65 Valiant 273 tranny. And I don't recall ever installing the special spacer. Then again, I was just 22, so some would say I was stupid, or ignorant. And I probably was,lol. I guess I drove that car about 2 or 3 years that way, before the thing gave up. It sure was fun while it lasted tho!
With an extra 20 cubes and less weight, I bet your 360 will be a blast!!
 
AJ is right about the balancer, I didn't think of that. You always use timing tape on to relocate the mark and then transfer all 273 over to the 360 and keep all your pumps and radiator as they are. Also I bolted a 904 with no spacers with no issues.
 
Litz said:
The pinch weld will have to be flattened to make room for the 727. I would like to use my cable shifted 904 from the original 273 engine but I don't think the converter will work with the 360 crank?
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Hey Liz,
Haven't been on here in quite some time. Hadn't seen this thread before.
On Tuesday, call Wildcat Mopars at 503-668-7786 on Tuesday. For only $20, they always have a few of the machined adapter rings that mate the smaller center torque convertor register of the early 904's to the later, larger crank center registers of the newer engines. Sorry, Right offhand, I don't recall what year that diameter changed, but I guarantee you need it for a '65 904 to a '74 360.
Mike in FL (hopefully soon back in OR)
 
Oldschoolcuda said:
That would be cool but unfortunately you are correct the converter will not work. The early 904's had an 18 spline input shaft and the 67 or so ups had a 27 spline input shaft plus a larger torque converter snout diameter. Your push button also would have a zero balance converter and you will need a balanced one for your 360.
Still, you should be able to find a reputable shop to modify snout and balance your push button trans converter to mate up to a 360.
Of course it will cost $
Pat Blais transmission is a good source for early to late modification
206-365-1966
Click to expand...

And, 2nd issue, since I didn't read the thread all the way through, is that your 273 torque convertor WILL work with the 360. Agreed, the 273 is neutral balance and the 360 is not, all you need to do is buy a 360 spec balance torque convertor plate from Summit, or anywhere else.

Mike (still wishing for OR) in FL
 
dodgedartgt said:
And, 2nd issue, since I didn't read the thread all the way through, is that your 273 torque convertor WILL work with the 360. Agreed, the 273 is neutral balance and the 360 is not, all you need to do is buy a 360 spec balance torque convertor plate from Summit, or anywhere else.

Mike (still wishing for OR) in FL
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Thanks for the info!
 
This is all great info. As usual from FABO.
As stated before in above posts. If your 273 trans is push button unit the early 273 converter will not mate up to the 360 crank correctly without snout modification or a pat blais or other adapter for snout.
Sounds like with snout adapter and balance plate you will be good to go if using early trans, which should be pretty light on your wallet.
 
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