Inline 6 to 350 SBC Swap - 1968 GMC

[@wrfarms9741]

Nice work! Looking great. That will be a nice truck to enjoy and used for utilitarian purposes. I believe I saw a 10 bolt rear axle out back. You might want to start looking for a 12 bolt positive traction rear axle for when that 10 bolt axle gives up the ghost. If and when you replace the rear axle, that will be a great time to do a disc brake conversion. Maybe an M-20, M-21, or M-22 four speed conversion in the future IF you can find one that someone missed in the junk yard. They are not cheap.

[@Challenged1]

You have a keen eye sir. That is a dana 44 out back. I'm not pushing too many horse puppies, so I have a feeling it may live. This truck is starting to come together!!!

[@richdetlaff-5983]

Wiring the same????

[@buddygotcha]

I’m currently doing the same thing in my 81 gmc the ole 250 is just tired and ready for an overhaul and I found a 350 sbc to replace it. I wonder if the same mounts and placements would work the same or did they change it up later down the road.

[@tannerwilcox8942]

I can tell you've lost weight. Keep it up

[@TylerSmith-gx4hs]

Great looking truck man. Im thinking about doing a 350 swap in a 1966 chevy c10 with an I6 and a 3 on the tree. Would it basically be the same procedure as yours?

[@Challenged1]

I believe so

[@joeclark9042]

Good video brother I know this is a long shot and I know it's about a year old but you still have that inline 6 by any chance

[@Challenged1]

I scrapped it.

[@joeclark9042]

@@Challenged1 dam ok thanks

[@ZackFrancik]

which headers did you use and did you have to modify the clutch linkage?

[@Challenged1]

I had to shorten the z-bar about a 1/2" and get the correct z-bar ball for the block. I used Flowtech 31000FLT Block Hugger Headers

[@ZackFrancik]

this is exactly what I needed. I just did my swap and can't find headers that fit without having to do any crazy mods to the clutch linkage. I shortened mine and did the ball, but didn't want to have to bend or cut anything else to get to work. Did that thrush exhaust basically bolt right up to the shorties?@@Challenged1

[@Challenged1]

@@ZackFrancik If you have a 3 on the tree, the linkage rod will interfere with the #7 exhaust tube. A little hammer persuasion makes it work fine though. The thrush exhaust worked well. I did also purchase the Flowtech 10010FLT Block Hugger tubes to connect to the headers and extend back to the exhaust.

[@ZackFrancik]

I've got the 4 speed sm465. I am assuming I will run into the same issue. I appreciate the help. This is the last piece to the puzzle for me to get this thing fired up.@@Challenged1

[@ZackFrancik]

One last question… I’m waiting on the headers to be delivered. Does the z bar go above the #7 headed pipe or below? I ask because I have .5” raised exhaust ports which could change clearance

[@jasonspeas5089]

Why wouldn’t the 292 engine mounts work

[@Challenged1]

The driver side perch is the same, but the passenger side is completely different.

[@AMV12S]

Things I would never do it... The 250 is much more stronger and resistant than the 350, some folks are taking 2000-2500hp from it.

[@Jarad-i6y]

350 has more torque And HP for half the price it would take to get a 250 like that

[@Diane-m2j]

Did you know that the engine mounts for the inline 6 will work if you move it forward to the next hole

[@Diane-m2j]

No three inch spacers needed for your fan .if you look at the engine mount where it sits for inline 6 cylinder there are holes right in front of the mount and that's where you want to mount.

[@Diane-m2j]

Slide mount forward to next hole and that's were v-8 mounts..

[@Challenged1]

You are correct. However, I would have to move the transmission forward and have a new driveshaft made.

[@Diane-m2j]

Your driveshaft should give you the distance you need.

[@Challenged1]

@@Diane-m2j It can't magically grow