'71-72 K-frames: BB vs SB??

rt-man · Post by **rt-man** » Tue Jan 06, 2009 5:49 pm

Is there really a difference between big block and small block K-frames in '71-72 B-bodies?? I'm getting closer to dropping a 440 into my '72 Sat Seb, which has it's original 318 sitting on a nice K-frame right now. Will that K-frame work? I keep seeing FS ads for BB K-frames for '71s.

Thanks in advance.

http://www.cardomain.com/ride/2648850

landon1 · Post by **landon1** » Tue Jan 06, 2009 6:19 pm

i cannot say 100% for sure, but my 71 satellite was a 318/904 car that was swapped for a 440/727....the power steering pump, hoses, radiator, etc are all 318 parts. i replaceced motor mounts a year or so ago and it doesn't appear that they have been changed either (i ordered 440 mounts), but they sell kits to convert mounts from small to big block....i did not do the swap, but i'm pretty sure that whoever did basically slapped in a 440 and used the accessories off of the old 318 with no other modifications. maybe that helps

rt-man · Post by **rt-man** » Tue Jan 06, 2009 6:44 pm

Thanks for the info, landon, but I was looking for a more focused answer on the K-frame over the accesories.

72RoadRunnerGTX · Post by **72RoadRunnerGTX** » Tue Jan 06, 2009 7:05 pm

Engine mounts on the K-frames are the same for all V8s except the hemi. There are with and without skid plate versions of the V8 k-frame. The 440 cars usually had the skid plate. Reproduction skid plates are for sale on e-bay from time to time, it is a pretty easy mod. With the correct BB motor mount brackets the 440 should drop right in.

landon1 · Post by **landon1** » Tue Jan 06, 2009 7:31 pm

basically that's what i was getting at...everything's the same really...certain people act like it's a HUGE deal swapping the motors, but in a B-body that could have any motor from the factory, it should be a direct bolt-in.

however, the radiator is up in the air....i now have an aluminum radiator, but the top hose is driver's side and the bottom is on the passenger side (small block style), due to the later-style water pump housing...so running a/c would be a problem, unless you use a 73-4 style radiator which has both inlet and outlet on the passenger side (what my plan is whenever i get to add a/c), or using a 71-2 big block radiator and the correct (not later-style) water pump housing.

71440 gtx · Post by **71440 gtx** » Wed Jan 07, 2009 8:09 pm

the 70-74 e body are same as 71-72 b- body

all 71-72 440 4bbl or 440 6bbl has a skid plate on k-frame

the 318 340 383 400 do not have one in 71-72

the bb mounts from a 66- 72 c - body are same ones for b- body if you need some

moparmodeler · Post by **moparmodeler** » Wed Jan 07, 2009 11:05 pm

The 225-B-body for 71-72 K- member has no skid plate and will not except a V-8 and there is no "kit" available to do a swap.

6o4o · Post by **6o4o** » Thu Jan 08, 2009 3:38 am

My 72 RR GTX with number matching engine doesn't have a skid plate on the k-member.. figure out...

moparite · Post by **moparite** » Sun May 03, 2009 12:03 pm

Nobody mentioned the motor mount brackets are different. Also the the torsion bars are thicker in the big block cars. The skid plates where also on the hemi's.

Road Runner Nest

'71-72 K-frames: BB vs SB??

'71-72 K-frames: BB vs SB??

Re: '71-72 K-frames: BB vs SB??

Re: '71-72 K-frames: BB vs SB??

Re: '71-72 K-frames: BB vs SB??

Re: '71-72 K-frames: BB vs SB??

Re: '71-72 K-frames: BB vs SB??

Re: '71-72 K-frames: BB vs SB??

Re: '71-72 K-frames: BB vs SB??

Re: '71-72 K-frames: BB vs SB??