While we're talking K frames BB and SB different?

[YY1]

I've heard 73 and up K frames are different due to an inch or so front to back to help with F/R weight distribution.

Schumacher (motor mounts) says they are the same.

But...Schumacher also wants you to trim the top inch off the pass side boss if putting a BB in an SB K.

If they're the same...WTF?

Also if it's true BB K bosses are an inch back, that brings four speed Z bar geometry into play.

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...and one more- are SB/BB spool mouths the same?

Looks like spools are all one piece, where biscuits are two.

I've got a 73 C body biscuit 400 and a 74 spool 318 sitting next to each other and it looks close.

Missing drivers side on 318, though.

When did C body go to spool?

 

[WP29440SE]

no , they are not the same . the drivers side k member boss is about 1 - 1 1/4" too far forward in a small block K member and needs to be fabricated. in order for me to drop a 440 in a 360 k member , (73 and up) without using conversion mounts , I had to do a little creative cutting and bolt the mounts to the block on the front side of the engine bosses. it equates to about 1" or so . otherwise , the transmission would not bolt up. I discovered this by mounting the tailshaft first , and then working the engine into the mounts. it sits at the right height , and I verified this off of an original big block car. the problem is working around the oil pump.

passenger side mock up, this side was not nearly as far off as the drivers side.

drivers side mock up at bottom. I don't have pics of the finished project, but these mounts are as solid as any now. this was just a mock to get an idea of what needed to be done.

 

[DART340H]

While on the subject. I have 69 coronet 440 which came with 318 auto from factory. What do i need to do to drop in 440 auto? Thanks for your input. Sorry don't mean to hijack this thread.

 

[nstyle73]

Schumacher simply shows the difference between a S6 and a V8 on their website and in their catalog. They do not show the difference between the SB and the BB, but if the SB and BB were the same, they would not have a product to sell ( the V8-B/RB mounts). However, it can be done without the conversion mounts, but based on the car I have that was done that way, I would not recommend it. There is a really good thread on here with pictures of the SB and BB side-by-side.

 

[moparmarks]

Just to add the spool mounting brackets are not the same between SB and BB. Bolt spacing where they bolt to the block is larger on BB.
73-8 K-frame frames are not the same as stated above as they do have separate listings and part numbers in the FPM.

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While on the subject. I have 69 coronet 440 which came with 318 auto from factory. What do i need to do to drop in 440 auto? Thanks for your input. Sorry don't mean to hijack this thread.

Mainly need 66-72B 70-1E 66-72C BB mounting brackets and a BB tranny. Probably need a BB radiator too.

 

[runnin74]

You might want to check out this thread.
http://www.forbbodiesonly.com/mopar...Identification-of-SB-vs-BB-K-Member-for-73-74

 

[Bruzilla]

Probably need a BB radiator too.

BB Radiator is a MUST. I learned that the hard way.