V1 John S's Full Cage Goblin - 07 SS/SC Donor

[JohnS]

Hey all, I'm finally getting started on my build and I figured I'd share it here to help keep me on track.

My main uses will be track days and autocross. This will replace my current car for these things (2014 Camaro SS, so this should be an infinite improvement)

Donor
I spotted a good deal on a donor on Facebook Marketplace last June for a 2007 Cobalt SS/SC. He was having issues with the ABS and AC he couldn't get cleared up and wanted it gone. Bought it, towed it home, stuck it in the garage and put it on the to-do list. It's pretty high mileage at 285k, so I figure the engine will probably need some refresh work, but it runs and drives well. ABS and AC issues obviously don't matter for this, so no concerns there.

Timeline so far
Ordered my kit in July, and discussing it with DF, we decided to take a little longer to get the large stage 3 items ready also so I could pick them all up at once.
Life gets in the way and kept me in a holding pattern until beginning of this month, when I started the process of stripping it down, and finally got out to Red Oak to collect the Phase 1 and Phase 3 parts.

The chassis is currently at Diamond Powder Coating in Austin, estimate came in at $1500, should be getting it back next week some time.
Tearing down the donor has proven pretty easy so far (the videos and this forum are a massive help), but I'm sure I'm going to find harder steps ahead. Hoping to get the subframe dropped and the powertrain out this week.

I'll try to stay diligent updating this when I make any progress.

-John

Donor still mostly intact


Donor as of 2/24/25


Chassis fits well enough in a 5x9 UHaul Trailer


Dropping it off for powder coating

 

[Rauq]

Can I be the first to say, make sure you save your parking brake tubes? Looks good, nice to see another LSJ build!

 

[Markm]

The forum is awesome. There’s a wealth of knowledge here. Don’t be afraid to ask questions and be sure to try out the search. The search bar took me a little bit to find what I was looking for but eventually I’d find something. Welcome to the group.

 

[Desert Sasqwatch]

John, welcome to the community. Looks like you have a good start going already. Take your time to label and take pics of EVERYTHING - you cannot have too many references to how things looked before taking them apart. Keep posting your progress and don't be afraid to ask ANY question, I'm certain that at least someone active on the forum has seen it before and has an answer.

 

[Ark :D]

Hello and welcome.

 

[Rttoys]

Can I be the first to say, make sure you save your parking brake tubes? Looks good, nice to see another LSJ build!

No no no. You have to wait for the right time to say that. You can’t just jump ahead

another Texan. Sweet.

 

[Doug Rostad]

Welcome John! As Desert Sasquatch said ,,,,,, Label everything!!! when the videos say cut this wire,,,,,, leave a few inches from the plug and keep every wire until the engine fires up in your Goblin. especially the brown and black and brown and white wires ! When you get the upper and lower control arms , chase the threads ! The cost of the tap will out weight the frustration of tight threads. I spent many frustrating weeks wondering why I could not get the car to start, after changing my clutch switch , another complete wiring harness about 6 ECU'S 5 BCM'S , 2 fuse blocks. I took it to a dealer and had them plug the test tool into the car and teach the BCM to see the clutch was engaged. 15 minutes later the technician had it starting with a $100.00 tip in his hand, at that point it was well worth the $209.00 and renting a trailer for them to do the job. The average DIY'ER can't buy the scan tool, (like I did) and pay GM $49.00 for the VIN code privilege to do it your self. You have to be a dealer. Put a few extra screws / rivenuts , pop rivets on the tunnel cover near the shifter. Spend the 10 hours to use the factory seat brackets. Yes there are about 12 Rivets to drill out. No they are not the easiest to remove! But, Mounted to after market racing seats they are amazingly easy to adjust the seats. I got my seats on E-Bay for $299.00 they look great! Safety harnesses from Race Quip.

 

[JohnS]

Thanks for the warm welcome and advice y'all!

Update: I was a little chaotic on my approach last night. Continued on the suspension components, the instructional video went into draining the transmission next but ADHD kicked in and I decided to start extracting the harnesses.

- Knuckles and hubs removed
- Fusebox removed
- Harnesses mostly freed from under the hood
- Coolant drained (to a nice spot on the floor right next to the pan I was aiming for)
- Some AC hoses removed

I have never been happier to spend money on the harness service than I am looking at the chaos that is this harness. Tonight I'm going to continue harness extraction, I'd like to get it in the mail to DF to get the ball rolling on that while I work on other stuff.

Next week I'll be recovering from surgery so won't be able to do much physical labor. I'm hoping to get the subframe and powertrain out this week so next week I can sit next to it and clean it.

-John

Knuckles/hubs removed:


Electrical chaos:

 

[Desert Sasqwatch]

Good luck with the surgery (hope it's nothing serious) and a speedy recovery so you can continue the teardown.

 

[JohnS]

It's fairly minor, just not allowed to do anything strenuous for a week after. Great excuse to make some of my buddies lug the chassis into the garage when I get it back from the powder coater.

 

[JohnS]

I am planning on doing the tubular subframe replacement, but right now the biggest decision I have to make is whether I want to move from the F35 to the F23. Internet opinions seem to favor the F23 for durability, but I have a F35 (with the LSD) that seems to be in fine working order.

I'd like to not have to purchase the whole subframe again if I decide to change later so I'm curious what people think about the two.

 

[Rauq]

I swapped out a working LSD F35 for a used F23 that I put an LSD into. I also installed DFKC's upgraded billet shifter at the same time, so it's not an apples to apples comparison, but in my opinion the best part of the upgrade is the better gearing. There's a noticeably smaller RPM drop on the 1-2 shift with the F23 vs the F35. In addition, with the 3.84 F23, gears 1-4 are all at least slightly shorter, and 5th is slightly longer, meaning better acceleration in 1st through 4th and a slight RPM drop in 5th on the highway. I feel like it shifts better at higher RPMs, as well, but that could just as easily be an imperfect F35 example vs a decent F23 example. It seemed to drive fine in the Cobalt. I agree that it seems consensus is that the F23 is more durable, but I don't know that an M62 LSJ is going to stress an F35.

Again, I only ran the F35 with the donor Cobalt shifter, so I don't know what the shift into reverse would feel like with a shifter without a detent or lockout, but I don't run the billet shifter reverse lockout with the F23, and it feels fine and perfectly safe. Then again, with the lockout collar in the reverse position on the Cobalt shifter and the F35 in the Goblin, getting into reverse was still a pain sometimes. Not sure if that was that particular trans, or shifter cables needing adjustment, or a sloppy Cobalt shifter (or a combination thereof most likely), but that was my experience.

I'm a big fan of the F23 swap, but I also got into it when there were $400 helical LSDs available, which doesn't seem to be the case anymore. But if you're ok with the price of a Quaife, I say go for it. I was able to sell my 4.05 ratio G85 F35 for $900 which was nice. I guess if someone's going to install a replacement trans, the LSJ F35 has more aggressive gearing than the LNF trans, so it's slightly more desirable.

 

[JohnS]

Thanks for the advice. I think I'm sold on the F23 swap. The trans is already going to have to come off the block to replace a leaking seal, and I'm already going to be buying the new subframe.Seems a good time to eat the one time cost of an F23 and a Quaife.

 

[Ross]

And there is a specific thermostat housing needed for the F23 swap. I think it is the base model thermostat... but not 100% sure.

 

[JohnS]

Update for tonight:

Dropped the subframe, and removed the radiator/condenser off the front to make removing wires easier.


Engine appears to be free at this point except for the exhaust, which is taking a bath in PB Blaster for the night.


I also confirmed a previous owner installed an ultra high flow cat:


Getting the powertrain dropped tomorrow is seeming pretty feasible at this point, but when looking for a place to attach chains, I see one real obvious anchor on the passenger side front of the engine, but can't for the life of me find another. Should I just be looping chain under the trans on the driver side?

-John

 

[Rauq]

And there is a specific thermostat housing needed for the F23 swap. I think it is the base model thermostat... but not 100% sure.

You need a base model thermostat housing and two coolant tees to emulate the LNF oil cooler coolant feed setup, link.

 

[TheAnesthetist]

Update for tonight:

Dropped the subframe, and removed the radiator/condenser off the front to make removing wires easier.
View attachment 51139

Engine appears to be free at this point except for the exhaust, which is taking a bath in PB Blaster for the night.
View attachment 51140

I also confirmed a previous owner installed an ultra high flow cat:
View attachment 51138

Getting the powertrain dropped tomorrow is seeming pretty feasible at this point, but when looking for a place to attach chains, I see one real obvious anchor on the passenger side front of the engine, but can't for the life of me find another. Should I just be looping chain under the trans on the driver side?

-John

cut the exhaust. no reason to be gentle with it.
As for getting the engine out, I found it was much easier to lower it onto a furniture dolly and then sawzall the front of the frame. Then you just roll it out.

 

[JohnS]

cut the exhaust. no reason to be gentle with it.
As for getting the engine out, I found it was much easier to lower it onto a furniture dolly and then sawzall the front of the frame. Then you just roll it out.

If the impact can't handle the exhaust bolts quickly, I'll bust out the sawzall.

I already planned on dropping it to a dolly but cutting the frame I hadn't thought about.

Thanks for the tips!

 

[TheAnesthetist]

This is how I did mine. Good luck!

 

[JohnS]

That looks pretty doable, we'll see how it goes tonight!