CK5
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73 K20....crossmember time

I finally found a cab for the truck. It's a pretty clean 73 gmc. I think it's a k20. It's got the entire interior, including pedals and a gun rack lol. It's baby shit brown with a mucus yellow stripe on the doors.... $150 with a pink and plates!
 
I gotta jump in here, I have lots of firsthand experience with the LS and the SBC..
I am on the fence like you, I love my sbc mainly because they're simple and dirt cheap to fix, bringing me to my first point, LS motors are not cheap to repair.. simple, I can get a waterpump for a sbc for 40$ new.. an ls 150-200.. i could go on about injectors gaskets, etc.. they're cheap to buy but are not cheap to maintain.. now they do not break nearly as much. So there is that, I would say they break 30% less, that's a guess..
all the trucks you have been in have torque management, any 6.0 truck has no power enrichment turned on, these two things make them embarrassing to be in.. its really a joke to let the rest of the drivetrain live.. if you knew that a lq9 was literally a cam and some other small parts away from being an ls2 you might think I am kidding, figure this, a lq4 makes roughly 320hp, an ls2 makes 400, the truck intake is better, the cam is smalller the exhaust is crap.. etc.. i can go on and on.. if you take a 6.0, stick an ebay ls2 or ls6 cam, tune it, disable tq mgmt, enable power enrichment, simply they kick ass.. then add a stroker, make it 416 ci, bigger cam, ported heads etc, they are ground pouders.. every bit as healthy as a 400..

Now, you just spent 3-5 grand making that engine happy and it isn't even in the truck yet.. I digress, I still think in my own warped way that is less work to put aluminum heads, cam, and maybe EFI(choose flavor) than swapping to LS.. 400hp is 400hp.. and to justify swapping you would have to drive the damn thing everyday.. aside the power potential and some of the reliability.. pound for pound I still think for under 500hp you cant go wrong either way, but if you have a fresh motor already in the truck or the parts to do it you might as well stick with the sbc..
 
Good input there! I definitely think youre right about the pcm over controlling the truck motors.

The importance of fuel injection has had me looking into LS motors more. I think for what i do i would want something with more torque...achieved through stroking!

My dad is building an LS7 right now so ive been watching him go through the motions.

After quite a bit of research ive arrived at what i would like to build IF the current motor is done. By the time i get my tax return i may just build a motor anyway...

I think to keep things somewhat reasonable as far as price goes i would get a new Lq9 block-$800
Keep the 4" bore and stroke it to 402. 408 is obviously more popular but engine shop machine work is expensive...probably another 6 or 7 hundred bucks...not worth the 6 cubes unless the block youre starting with is jacked. This also leaves room down the road...

Seems like a rotating assembly would be about $1200 max....

I would do the clearancing myself, with dads help of course for my first motor build. Not sure on heads but i dont need anything crazy. Im thinking i could arrive at 3 grand for the whole thing said and done minus the comp and some other stuff. The numbers are impressive on the 402/408 motors. Seems pretty easy to make a bit more than 400 hp.
 
Yes that would be a stout combo if you consider a stock ls3 makes 420+ I've seen them make 480-500 with a mild cam and porting. Texas speed has some nice combos you might check out.
 
yeah certainly impressive numbers! The torque of the stroker is what does it for me! I was just reading a NA 402 with a bunch of goodies and a good size cam...530rwhp

If i hit 400 id be way happy. It looks like people are making 300ftlbs at 1800 rpm...which is sweet!

Cab pics are attached! No real rust spots. Got some interior pics to upload...

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Hydraulic pedals did not come around till 1985.

Anyone who would go through the work of swapping out a set of mechanical pedals to hydraulic pedals, would know what they had, and would have advertised that.

I guarantee it has mechanical pedals.

Martin
 
Well I picked up the cab this weekend. I ended up taking the k20 frame with it just because it had 56s on it, it made it easier to load onto the trailer and it was free. Ive been thinking a lot lately about the blazer vs single cab body and what my needs are. As much as I really love the openness of the blazer it has some drawbacks to it. I think to suit my needs better I may go with the trazer style truck....single cab on k5 frame with a tube bed.

The one thing I cant do easily with the k5 is leave it outside. The massive ferral cat population would commandeer it over night. I really hate putting the top on and my garage really doesnt suit a pulley system so I can easily put it on and take it off...which means I have to rally people together to move it around. Itd be nice to just lock a truck up and keep it outside when im not working on it so I can maintain my other vehicles. Changing brakes outside on a steep hill isnt exactly fun...

Still thinking it over some.








This picture has me thinking...

 
I don't regret one bit doing the Trazer swap so far... obviously I haven't driven it yet but its been very straightforward. If you need measurements or anything, let me know.
 
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