66 GMC Long to Short LS Swap

[Duncan K]

I've been plugging away on the frame lately. Really pushing to get all the new cross members done and everything welded up so I can get this thing blasted and lay down some paint. I am really tired of rust, just can't wait to have at least one piece of this truck cleaned up and looking like new! Its been a bit like Christmas for me with boxes of shiny parts showing up at my door. Headers came in as well as my Grand Slam kit from CPP. Got my power steering kit from POL as well.

Finished up the notches for both sides and got them welded in. I'll probably box in the insides for good measure.



Ground the welds flat on the inside of the frame rails where I shortened the frame. Made up some fish plates and welded them in.



Fabbed up a new cross member to replace the twisted and bent one up front. Decided to get a little Tig practice in. Slowly getting better at it.



Mounted up the new PS box and plates and welded them in along with the finished cross member up front.



Just one cross member left to build and that is for the transmission. Got to work setting the motor and trans in. Had to move the stock V8 perches up to the front mounting holes. Bolted up the Speed Engineering LS swap motor mounts and put the old rubber mounts in the rear hole locations to set the motor as far forward as possible and dropped the motor in. As it sits right now the oil pan is sitting on the the front clip and the rubber mounts aren't quite fully seated on the perches so it looks like I will have to shim the perches up a little. I took a quick measurement and the motor is going to be really close to the fire wall, I'll have to throw the cab on to see just how close.
Headers are from Speed Engineering as well. They bolted in and fit like a glove inside the frame rails. I'll have to trim one little piece on the bell housing on the passenger side to make them work.





I am hoping to get the position of the motor finalized tomorrow and start building the trans cross member. Gotta do some homework on setting the driveline angle. Plan is to use a magnetic angle gauge on the end output shaft of the trans. From the reading I've done I need to match the angle of the output on the diff. Should I zero the gauge out on the frame rail before measuring the angle of the diff?

[Rusty63]

very nice,and nice welds,i tried tig 30 yrs ago stuck with stick and mig LOL,nice job on crossmember!

[tinydb84]

Originally Posted by Duncan K

I am hoping to get the position of the motor finalized tomorrow and start building the trans cross member. Gotta do some homework on setting the driveline angle. Plan is to use a magnetic angle gauge on the end output shaft of the trans. From the reading I've done I need to match the angle of the output on the diff. Should I zero the gauge out on the frame rail before measuring the angle of the diff?

I set the frame at 0 degrees, put the motor and trans around 3 degrees down using the trans crossmember, and then set the rear end to 3 degrees up.

Its not very hard once you are there doing it.

[1enick72]

Nice work, following.

[Duncan K]

Well I got the motor and trans in their final position. Had the motor in and out several times to change the position of the mounts and the perches to get everything to clear. Haven't had a chance to put the cab back on to check firewall clearance. Judging by the measurements I took its gonna be close.

Got to work building the trans mount. I quiet often draw everything out on my welding table and use that to lay out the parts.



Tig welded the parts up



Centred and squared it up, then drilled it for a couple 1/2" bolts



Right now the transmission is set at 5 degrees but will be easy to shim if needed. I jacked the frame up level and checked the angle of the differential. It is sitting at 10 degrees up. I'm hoping that will decrease a bit when I put the lowering springs in. Then I guess I'll have to shim it the rest of the way to match the transmission.

I'll be getting to work stripping the suspension off and get everything sandblasted. Getting closer to paint and shiny new parts!!!

[tinydb84]

Id make the center of the lower section of your trans crossmember thicker. Strength is gained by the height of steel not the thickness.

[Notch1988]

Originally Posted by tinydb84

Id make the center of the lower section of your trans crossmember thicker. Strength is gained by the height of steel not the thickness.

I would bet that crossmember could handle the weight of the entire truck with little to no deflection.

[Duncan K]

Originally Posted by tinydb84

Id make the center of the lower section of your trans crossmember thicker. Strength is gained by the height of steel not the thickness.

I thought about beefing up the bottom a bit more but decided the 3/8 flat bar was enough. After getting it welded up it is pretty stout, the frame rail its mounted to will bend before it does.

Got my Boyd's tank from UPS today. Man is this thing pretty!! Welds are a thing of beauty, it will be a real shame to hide this thing under the bed. I really like that it came complete with in tank pump and sending unit.



Started working on getting the front suspension off. Couple hours with a torch, big hammer, pickle fork and a lot of swearing got the job done.



Found both springs were broken when I pulled them out.

[Duncan K]

Finished removing the rest of the suspension. Old ball joints are out, trailing arms off. Ready to get everything sandblasted.



Hoping to get everything painted, reassembled and back as a full roller in the next few weeks.

[Nanook]

Nice build thread.
Currently working in the Calgary area so maybe will get to see the build when completed!

[Duncan K]

First round of blasting got done this afternoon. Took the suspension parts down to try out a DIY sandblasting place. Best money I have spent in a while!! Endless high pressure air supply, no waiting, no clean up. Feels so good to have a few parts without rust and 50 years of grime on them. Hoping to head back there with the frame and the rear end in the morning. Supposed to snow for the next 4 days starting mid morning so I have to get this done quick.

[slimjim66]

That’s awesome man, a DIY blasting place is a great idea. Never heard of that before. Build is looking good

[Captainfab]

Ha, I've never heard of a DIY blast place. What sort of blast media is used?

Excellent job blasting. That's how the blasted parts should look, 100% white metal. Be careful doing any sheetmetal.

[Duncan K]

Yeah this place is great. The media is a medium grit sand. Took care of the rust and grime really quick but didn't seem to dig into the metal. It sits on 5 acres and has 6-7 stations big enough to bring a large trailer.

I loaded up the frame and rear end and tried to beat the snow storm this morning. Got half way to the blasting place and the storm hit. Looks like I will be waiting another week before I can get the frame blasted. Will probably tear down the LS and see what kind of shape its in. Plan is to send it off to be hot tanked and honed. Hoping I can reuse the pistons and just re-ring them. I'll be replacing all the seals and gaskets.

Not sure what I want to do for a cam. I want something that will work with the stock motor for now and L92 heads in the future.

[Notch1988]

Do they charge by the hour? How much is it?

[Duncan K]

Originally Posted by Notch1988

Do they charge by the hour? How much is it?

$150/hr, took me 40 min to do the suspension parts

[Captainfab]

Wow! My blaster charges $60 hr and he does the work.

Originally Posted by Duncan K

$150/hr, took me 40 min to do the suspension parts

[SkinnyG]

Canada. Ain't nothing cheap up here

[mongocanfly]

diy blasting...new one on me to...and that does sound high at 150/hr....like you said..Canada $$...what can you do...

[Duncan K]

Caught a break in the weather today. Frame and rear end are blasted.

[Notch1988]

Everything looks great. What's the plan for paint?

[Duncan K]

Originally Posted by Notch1988

Everything looks great. What's the plan for paint?

Semi gloss black on the frame and suspension parts. Got a start on it yesterday.

[Notch1988]

Brush on POR15?

[Duncan K]

Originally Posted by Notch1988

Brush on POR15?

Used Tremclad. I might bag this truck in the future which would require mods to the frame and arms. I've read that once you put Por15 on the metal doesn't weld very well even after grinding it off. I also like the idea of easy spray can touch ups.

My kids came out to help me paint the frame today. The extra hands made short work of it. Hope to get it flipped over and the other side painted tomorrow.

[northern 85]

Looks fantastic! Its great to see kids smiling while working!!