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Back in 2021 I picked up my cobalt, it had a few performance upgrades at the time. GM stage 2 pulley, ZZP exhaust, ZZP s3 front mount heat exchanger, and an injen CAI. The car had 84k miles and wasn't in too bad of shape overall. Pretty much stock as far as suspension/interior goes. ZZP lowering springs and some aftermarket wheels that actually suit the car very well! My plan was to just keep this car as a fun daily driver, and not do too much else to it. But that went out the window quickly lol. I ordered a 2.8 pulley, ZZP 3in CAI, new coupler and oil for the supercharger, dual pass endplate, and option B kit. Right before installing these parts, I noticed a leak from the trans, between the bellhousing and block, leaking slave/tob. So a new GMPP clutch kit also got ordered. I do not have any pictures of the engine bay after doing all of this, but I do have a before photo from when I picked the car up! Next post I'll detail how the turbo swap came about.
Last edited by schmitty_z; Nov 9, 2023 at 09:36 AM.
*I've included some more photos/info from the previous phase of the build* The car came with both the low rise and high rise wings. I can't stand the low rise look, so I immediately swapped that out. I also hate a dirty engine bay, so I took the time to wipe down whatever I could and gave some new life to the supercharger and intake manifold after the coupler/oil change, I also replaced the o-rings in the manifold while it was out. Really wish I had a photo of when it was all back together before the turbo swap, but oh well! Right when I thought I was "done" with wrenching on this thing, a buddy hit me up with a deal I couldn't turn down. A full Hahn turbo swap kit, turbo needed rebuilt, for $300. Every pipe, coupler, clamp, even new oil feed/return lines! Thanks to YouTube, I was able to rebuild the turbo myself for about $160 and a couple hours of time. Powder coated the compressor housing too! Lots of pics throughout this process. Supercharged goodies Blower maintenance ft Tyler from ZZP! Brand new again Turbo parts pile Damage to turbine Powder coat time Not bad for a YouTube mechanic lol
Last edited by schmitty_z; Nov 9, 2023 at 10:22 AM.
Now I'll deep dive into the turbo install stuff! A few things I had to do during this time: inspect timing chain, replace valve cover gasket, one step colder plugs, and while the VC was off, I had it powdercoated as well! Yes, that means removing the baffles, tapping some holes afterwards, all that fun stuff lol but worth it! Installing the exhaust manifold was straight forward, and plenty of room to work with having the VC off. The intake manifold put up a fight with me. Not really sure why, but it just did not want to sit flush and line up. Eventually I did get it on, though! The LSJ alternator has to be swapped out also, did I mention the same friend that sold me the kit, also gave me the alternator I needed as well?! There will be more from that guy later... Lol. Alternator pigtail was different so spliced that in, very easy process. Quick trip to the junkyard for belt tensioner and the accessory system is all good to go! Used the 1 less rib belt from base model with no issues. On to intercooler and piping, the Hahn kit has a very unique routing compared to most other LSJ turbo kits. Piecing this together with essentially no reference was a little confusing but it all came together nice. Next I dropped the oil pan, and tapped it for the oil return fitting. Oil feed line screwed right into back side of block, tight space but once you get a wrench on it, no problem. Then the fun part.. getting the turbo bolted to the manifold. Feel like I turned that turbo every angle possible for so long until finally it slipped up through. Thought I was gonna have to pull the axle out for clearance! Haha. Definitely not looking forward to pulling that out when it's time to go bigger. Downpipe/exhaust went on very easy, fitment was great. I really like the kit itself, just wish it was external wastegate! Timing chain looked great! Also can see where my valve cover leak was. Color reminds me of the "shock yellow" on the new Camaros. Manifold and turbo finally together! And yes, I removed that firewall shielding lol Old supercharged exhaust, vs new turbo exhaust If you ever wondered what a 90k LSJ looks like inside Simple, effective Oh yeah, that's a drain line alright. Started to get really excited at this point! And basically done at this point! That turbo intake pipe is a bit odd and tight to fit but, it works
This post should wrap up the turbo install. Couple pics that should've been included with last post. So with any boosted engine it's always been my preference to run a catch can. Just makes me feel better lol. I don't have any detailed images of the can itself or where I mounted it, but I can describe how I ran my set up. Port from VC to vented can. Oil cap AN fitting (LS style, works like a charm) also to vented can. I mounted the can in front of my radiator fan below the intake manifold. Easily drained from underneath the car during oil change! And man do those new headlights look 100000x better than the yellowed old style! Also, I forgot to mention originally, the car already had 60lb injectors when I got it. Was a nice surprise. After ensuring there were no leaks, I was able to get a base tune on the car. Spent the next month sending logs back and forth with my tuner Eric King and got it dialed in running strong on gate pressure 93octane. Once again, thanks to my buddy for loaning me his HPTuners interface for going on half a year now lol! No power numbers, but if I had to guess, low-mid 300s whp. But of course, I did not stop there. In order to run more than 17.5psi on these cars, you have to do a fuel system overhaul! So that was my next project. Alternator pigtail splicing Looks factory again! Catch can installed New headlights The odd hot-side pipe routing of the hahn kit. Headlights mounted and bumper on!
Last edited by schmitty_z; Nov 9, 2023 at 12:25 PM.
Fuel system time! OTTP rail + FuelLab regulator (thanks Joel!), AEM 320 pump, Aeromotive fuel filter, and a bunch of -10AN braided fuel hose. Also, since there is no E85 close to me, on my boosted builds I run methanol injection. So also installed a Snow Performance kit with the VC-30 progressive controller. I refreshed some of the front suspension too, as it was well past it's good days. New KYB struts, top hats, wheel bearings, and sway bar end links. Not many photos of the fuel system install, since I was involved in a motorcycle accident during that time and couldn't do most of the work myself, I had a friend handle dropping the tank, installing fuel pump, and running the return hose. He also threw in my ZZP coolant hoses I've had laying around for a while. And of course, to make all of this worth while, a TurboSmart manual boost controller. Rear brakes needed serviced so knocked those out. Thanks to the Hahn intercooler piping, I was able to run a strut bar also! Threw some stickers on too, it was too plain under there. New rear pads/rotors Not winning any show car awards but, it certainly works! Wideband AFR gauge and peep the electronic boost/methanol display Controller hidden nicely behind the lower dash panel Suspension goodies
Fuel stuffs This is how she currently sits!
Last edited by schmitty_z; Nov 9, 2023 at 12:30 PM.
Isn't it amazing how our plans to do just 1 thing or 2 leads to being an addiction to performance modifications, simply because of a deal that can't be turned down. I totally understand all of your upgrades and I hope that you enjoy your newly found power and handling. I love what you did to your 'new to you' Cobalt. I hope you have fun with your Cobalt. Do you plan to track your car at all or is it just to enjoy the new get up and go as well as sticking to the corners better on your regular drives?
Isn't it amazing how our plans to do just 1 thing or 2 leads to being an addiction to performance modifications, simply because of a deal that can't be turned down. I totally understand all of your upgrades and I hope that you enjoy your newly found power and handling. I love what you did to your 'new to you' Cobalt. I hope you have fun with your Cobalt. Do you plan to track your car at all or is it just to enjoy the new get up and go as well as sticking to the corners better on your regular drives?
The car is an absolute blast to drive now. It was fun before, but it’s really fun now that it can outrun most of the newer muscle cars around the area haha. It’s my daily driver so I don’t plan on tracking it, but I definitely don’t back down from some highway pulls when the opportunity presents itself! I may take it down the drag strip just to see what it will do, but that’s about it.
The car is an absolute blast to drive now. It was fun before, but it’s really fun now that it can outrun most of the newer muscle cars around the area haha. It’s my daily driver so I don’t plan on tracking it, but I definitely don’t back down from some highway pulls when the opportunity presents itself! I may take it down the drag strip just to see what it will do, but that’s about it.
These are definitely fun cars to drive and they surprise many other drivers with the power Cobalts have. Even with a few mods, like you have done, these cars are so much fun to drive. I really wish GM hadn't discontinued the Cobalt but many of us have continued to really have a blast showing other drivers what these cars are capable of. I hope you have fun driving your Cobalt for any years to come.
Been a while, nothing too exciting has happened but suppose I’ll throw an update in. I put the car on a dyno a couple of months ago, on ~18psi but with a boost leak, tapering off to about 16 at redline, it put down 302whp 347tq. I was okay with that! I found a hole in my hot side pipe where at some point it rubbed against my axle. Had a friend weld a bracket to the pipe so I could ensure it wouldn’t happen again. Also found a split hose at the T fitting for my FPR/meth map. I’ve since turned the boost up to 20psi and it’s been solid! I also grabbed a set of 80lb injectors, and I’m hoping to pick up a cortex EBC as well. Maybe a larger turbo after I max the 20g out! Got super lucky and snagged a carbon fiber c7 style hood (painted flat black) for a killer deal, $350! Had a buddy wrap it with a forged carbon pattern. Turned out pretty decent! Had the center part of the wing done to match.
