I know I’m not alone here, and I believe once anyone starts to modify their car, they get to a certain point where they think, yeah, I need more power. Well, I have reached that point.
I have been pleased, for the most part, with the tune on the stock turbo. I have added a few things, such as the flex-fuel upgrade, intake, downpipe, and exhaust, but I have been itching for more. I knew Brian from Vermont Tuning had been working on a turbo upgrade for his Cruze, so I checked his website to see if he was selling anything for an upgrade. I didn’t see anything, so I hit him up to find out if he had any plans to make upgrades available. Unfortunately, he didn’t, but he was happy to advise me on what I needed to do to upgrade the turbo and tune it for me as well.
The first thing he advised was an upgrade to forged pistons and stiffer valve springs, which I purchased from him. Apparently, the stock cast pistons aren’t that strong and can fracture under higher cylinder pressures (above 21 psi). The forged pistons also have reduced compression at 9.0:1 compared to the stock 9.5:1, which Brian explained was friendlier for high-boost applications. The stiffer valve springs are to prevent valve float. He didn’t mention anything about the rods, but ZZPerformance offers rods for the 1.4L, so I figured why not since the engine was going to be apart anyway.
I’ve never rebuilt an engine before, and I wasn’t going to start with this one, so I contacted Piper Motorsport, the race shop I use for fabrication work, to see if they could recommend a good machine shop. Luckily, there was a machine shop just a few doors down from their shop, Classic Motors. I contacted them, and they were more than happy to help me with this project.
The plan was to have the engine rebuilt and broken in before I started the turbo upgrade. To make it easier and save money, I pulled the engine myself and took it to Classic Motors for the rebuild. I also had them help me with machining an adapter plate for the oil cooler upgrade I wrote about in an earlier post.
Once the engine was rebuilt, I installed it back in the car, finished the oil cooler upgrade, and fired it up. Everything looked and ran well, so the next step is to break the engine in and start planning for a bigger turbo!
DS
