slant 6 to 318 conversion

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banditluda

banditluda

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Hi there! First of all, what transmission came stock in a 74 Duster slant six car? Secondly, with that transmission work with a 318? Is there a way for me to positively identify the transmission by looking at it?

Thanks!
 
rc_brooks said:
It should be a 904.


and yes, it will bolt up to a 318.
Click to expand...

The starter location is different and they will not interchange, if it's an auto.

If it's a manual, yeah you can use it on the 318. I used my slant's 3 speed on my 318 and on my 340. All it took was a new bellhousing, flywheel, clutch and pressure plate. For the most part at least.
 
Ok, so it doesn't matter if its a 904 or 727, but I will need a small block tranny to go with the engine, correct? Also, aside from the standard motor mount changes, is there any differences mounting the small block tranny in place?
 
banditluda said:
Ok, so it doesn't matter if its a 904 or 727, but I will need a small block tranny to go with the engine, correct? Also, aside from the standard motor mount changes, is there any differences mounting the small block tranny in place?
Click to expand...

They mount in the same place, so you shouldn't run into any issues there. You may need to address the driveshaft if there's a difference in the length of the transmission. A 727 also takes a different yoke than a 904. If you stick with a 904 then everything should bolt back up BUT...what rear end do you have? If it's a 7 1/4 then you might blow it up when you drop a V8 in. New rear end = new driveshaft.

All said and done, it's a pretty straight forward swap. Going from a slant to a small block is pretty easy.
 
Lol,... 1st you prob. want the eng. swap forum to be proper, 2nd, no. The trans if it's
auto is definitely an A904(TF6), unless someone swapped in the relatively rare A727 unit
w/the 6 cyl. case. Either way it ain't boltin' up to your small-block. You'd need an A998-
A999 version w/the SB belhousing,and a shorter throttle cable,and the kickdown linkage/
rods,and a different k-frame/schumacher conversion mounts,etc.
If it's a stick, a minimum of bellhousing,flywheel/clutch assy., bellcrank pivots/bracket
and rods..... start searchin' these answers have been given many o' time........
:coffee2:
 
Its an automatic.. just so there's no more confusion about that. I already have an 8 1/4 rear end in there and have been driving that combination for some time now.
 
I also already have a V8 K frame from a 72 that has been refinished and ready to go, but the car is a 73. Am I better off to swap K frames and avoid buying the brackets, or would there be more issues trying to do the k frame swap?
 
banditluda said:
Ok, so it doesn't matter if its a 904 or 727, but I will need a small block tranny to go with the engine, correct? Also, aside from the standard motor mount changes, is there any differences mounting the small block tranny in place?
Click to expand...

Incorrect and correct. It does matter if it's 904 vs 727 slipyoke size and driveshaft
length wise, but yes it must be SB. As mentioned, if you're changing rears to 8.25/8.75
now is the time if you need to change driveshaft length, 8.25 needs approx. 1.6 shorter,
8.75 needs over 2" shorter. If you go 727 you will subtract another 4".
 
banditluda said:
I also already have a V8 K frame from a 72 that has been refinished and ready to go, but the car is a 73. Am I better off to swap K frames and avoid buying the brackets, or would there be more issues trying to do the k frame swap?
Click to expand...

Cool, I would use a built A998/999 then, and '73 /6 had spool mounts? If they have a
conversion mount that worked I'd stay w/the spool mounts....just me. :coffee2:
 
So, in reality, the best thing to do then is to find a donor A body with the drive-train I want to ensure I have the correct parts to do the swap. I'm basically trying to keep my costs as minimal as possible. I've had this /6 in this car for way too many years. It just needs a V8 and my budget is all but non existent lol.
 
banditluda said:
I also already have a V8 K frame from a 72 that has been refinished and ready to go, but the car is a 73. Am I better off to swap K frames and avoid buying the brackets, or would there be more issues trying to do the k frame swap?
Click to expand...

When I swapped I just used Schumacher conversion mounts. It was quick and easy. Everything bolted up like it was supposed to. A K frame swap would be a lot more work. It's up to you though.

Since you're on a budget, your best bet is to find a 318/904 combo that's complete, and then drop it in. The 904 will bolt right up, your driveshaft will work too. You'll need a radiator, mounts, exhaust, and a few other things depending on how complete your donor motor is.

I swapped when I was a freshman in college. AKA when I was on a budget. It's definitely doable and doesn't have to cost a fortune.
 
BlueDream said:
The starter location is different and they will not interchange, if it's an auto.

If it's a manual, yeah you can use it on the 318. I used my slant's 3 speed on my 318 and on my 340. All it took was a new bellhousing, flywheel, clutch and pressure plate. For the most part at least.
Click to expand...

Wow, never realized the auto wouldn't bolt up. Learn something new everyday. I've never owned a /6 but I've pillaged plenty of parts off of them. Well good to know. I have always oriented the /6 in with the 3.9 in my mind.
 
just changed a 6 to a 318, 74 duster,have a 8,25 rear end, didnt want to change k member, used shumacher mounts,requires drivers side motor mount to be shortened, and a 9/16 hole to be drilled,template comes with mounts, used a 904 from small block,drive shaft worked that came with 6 ,,,you add 180 lbs by going 318, but i used a aluminum intake and headers which removed nearly 100 lbs,all they recommend to change is shocks, and according to headers you have to change the steering arm to a v8 car, it has a curve , the 6 cylinder is straight arm
 
So... I'm dry fitting my 318 block to my 72 k frame.... and one things not right. It seems like a weird problem to have. The mounts look like any of the pictures I've seen say they should. But there are seemingly 2 issues. The drivers side mount location on the k frame seems to be oriented further forward than the passenger side, but the mounting locations on the block look to be relatively symmetrical. Also, aside from that, the mounting locations seem to be too wide. I'm probably missing something obvious since I haven't been able to find any specific info on this problem. Does anyone have any insight?
 
Pictures would help.
Do you have the transmission attached and ready to mount as well? The tailshaft when installed can pull it together a little bit.

Are the mounts on the correct sides?
(Block and K frame mounting points?)

What swap kit are you using?
 
20160919_222135.jpg
20160919_222112.jpg

I'm just mocking it up to make sure it would fit. Im essentially just lifting the k frame up to the engine on the stand. I used a second passenger side (from the original Fury mount that came with the engine) and that seemed to fix the alignment issue... but the width. There is a few inches for sure when I put one side in the mount hole.
 
Then there should be no problem save the mounts being crushed/worn.
Being that it is not in the car and being mounted up with the trans in its space, I find it hard to tell (even more so from here) if it is out of wack or not.

Things have a funny way of fitting in nicely when there in the car the way there supposed to be and not outside the car loose and flimsy.

Perhaps someone else knows via the description and pictures.
 
It seems as though if there were mounts at least twice the thickness as what exists in the pictures, it would be closer. Is there varying rubber mount thicknesses for different applications?
 
No, not that I'm aware of. If the engine mounts are from an A body 318, is so no problems.

But from a B or E or F body, there may be a difference in mount thickness and such.
This however, I am not aware of.
 
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