Build thread for 80 stepside
 

Starting a build thread and I’ll love input and suggestions!

Picked this 1980 gmc step side over the summer for DIRT cheap. 305/th350 with some performance goodies, stock suspension, junk brakes, and rotted floor pans and rockers

Gonna be starting the build here with my girlfriend for the winter as she wants to start building vehicles with me

The PLAN is a simple 5/7 drop, disc brakes, all new lines, fix all the wiring, fix all the rot, and get it running good

First thing to decide on is the engine! Has that 305 in it but I kinda want to put that in a s10 jimmy I’m buying so I’m looking at either a hopped up 350 with 400 or nice 5.3 with around 450 horse ... keeping auto of course ( the plan is a nice street/strip truck in the end

I’ll be posting progress as we do it slowly! Any input on the swap ideas would be awesome as I’m fairly certain on a 5.3 but I love to hear different ideas and pros and cons

Re: Build thread for 80 stepside
 

I would serious consider going for a over drive. My personal favorite is the brand F 4R70 from the crown vic. To which I use a ultra bellfor the conversion. While it is still a wide ratio trans. It is not as bad as the 4L65. Which would be my second choice.

With a overdrive you can have something on the order of 4.33 gears with the OD vs 3.23's with the th400.

That makes even a basic revy 350 dynamite 0-60. Which is where as a street truck you really want the power to the wheels. Which is what most people want.

If you do the 5.3 use the 4L65E, and a Trailblazer torque converter. The converter is almost a 2500rpm stall for about $250 vs the 700+ others can cost, and works good with a basic built engine.

Re: Build thread for 80 stepside
 

If your wanting to upgrade the engine then I'd go for the 5.3 swap...use whatever trans comes with it..most probably a 4l60...just be sure to get it complete...the earlier yrs of production have less headaches to overcome....no DOD or afm....if its dbw be sure to get the gas pedal that matches the engine throttle...
will be a fun project..

Re: Build thread for 80 stepside
 

Yes I plan to get a early 2000s 5.3 with a 4l60 or 4l80

Just deciding whether I want to get a donor car or not as that’ll be a bit more money and I don’t want any more shells on the yard for the winter ... might be easier to just get a swap someone pulled out or maybe my shop teacher has one

Re: Build thread for 80 stepside
 

Where I am you can get used Tahoe/Suburban quite cheap, but still runners.

If you plan to use items out truck it can be a good deal, but if you only want the engine/trans. It can quickly turn it into more work then it's worth. Unless your on a really tight budget, and can sell items to recoup expenses.

One option that maybe a lot of fun is to grab a 4x4, and convert it to awd. Then swap it under your C10, or graft the frames together. Someone did it with a trailblazer, and it didn't look to hard if your decent at fabbing stuff up.

Re: Build thread for 80 stepside
 

I’ll be doing drive by cable, aftermarket harness, and all that so really all I’ll need is the engine, transmission, and computer which is why I’m leaning away from a donor ..

I was looking at awd but not for this truck .. I’ve got a 92 k1500 blazer I have been collecting parts to put a 6.0 into .. I wanna lower it and keep4wd or go awd ... but that won’t happen for a long time as the truck is still in perfect shape and at 300k the original 700r/350 are still kicking amazing

Re: Build thread for 80 stepside
 

Try Car-Part.com they can have good deals. I found them helping my friend look for a engine for his truck.

Re: Build thread for 80 stepside
 

I will try that thank you

Re: Build thread for 80 stepside
 

Thinking about using the “PAINLESS” ( brand ) chassis harness and engine harness to make everything fresh ... the wiring in this truck now is ... well let’s not talk about it .. it makes me sad just looking at how someone is that idiotic

I’ll have to read into them more... I know a couple people have had problems with the engine harness but that’s easy enough to fix... the chassis harness is what I’m more concerned about

Re: Build thread for 80 stepside
 

love the stepper... moving this to the builds section so its easier to track

Re: Build thread for 80 stepside
 

Thank you

I’m new here still so don’t quite fully know where to put stuff

Re: Build thread for 80 stepside
 

Got the box off today... first time for that .. first time owning a pickup actually as I only own a 2wd k5 and 67 panel truck ... so no box’s on those!

Gonna clean up the frame in prep for the c notch and drop

Re: Build thread for 80 stepside
 

Got the 305 out

Gonna clean it up and give it a REALLY good soak

It is supposed to be a bright blue... yikes ...

Gonna do every single seal to it and I have a cam and timing kit laying around I’ll throw in

Gotta figure out where this oil is coming from ... seems like the headgasket ...

Re: Build thread for 80 stepside
 

The two biggest culprits are improperly installed intake manifolds, and old valve cover gaskets.

When you get the valve cover gaskets use the blue rubber versions. They seal so much better. As for the manifold use the good silicone, and let it dry for at least a day.

Re: Build thread for 80 stepside
 

Got the engine cleaned up and now the harmonic balancer is stuck on there! Argh! Pulley won’t do it and slide hammer won’t do it I’m at a loss here

Never had one stuck this bad

Re: Build thread for 80 stepside
 

Ouch

Lots of metal in that oil... not sure it’s worth fixing

Guess I gotta be on the lookout for another engine... just to decide between 350/383 or 5.3

Re: Build thread for 80 stepside
 

Didn’t do anything on the stepside today ... feel a bit defeated with all that went wrong

But I got to move around my 67 gmc panel and try out my new trailer ...

Drag radials on the back of the jimmy DO NOT like that much weight!

Re: Build thread for 80 stepside
 

The things the previous owners did are starting to give me an aneurism ... how do I even fix this ? Like why would someone weld this much on there ?

It’s the shock mounts bolt

Re: Build thread for 80 stepside
 

:uhmk::uhmk::uhmk: I always wonder when I see things like that. I am sure that in my youth some of the things I did to keep things rolling would make peoples head turn. BTW, beautiful looking Jimmy.

Re: Build thread for 80 stepside
 

Thank you!

I’m still quite young ( 17 ) but my dad used to build hot rods so I learned very young that I need to do the right thing the first time instead of the wrong thing ten times

Re: Build thread for 80 stepside
 

Got the cab off today ... very pleased with the frame other than that one shock mount ... very very rust free ( just surface ) for being a northern frame that sat in a field for so long.

Now to clean it up ... I’d like to powdercoat it but I’m not sure it’s in the budget right now if I also want to get a 4 link setup ... so maybe take it down to raw metal, primer, paint, and down the road I’ll get it powdercoated