Chevrolet Camaro SS STS Turbo System Install - Bookin' By The Book, Part 6 - Tech
Buttoning Up The Install Of Our LS1 Camaro SS Project Car's 50-State-Legal STS Turbo System
From the November, 2010 issue of GM High-Tech Performance
By Chris Werner
Photography by Chris Werner, Gary Werner
Leaving you halfway through the installation of an STS turbocharger system on Project CT ("Bookin' by the Book, Part 5," Sept. '10) probably annoyed some of you. You were likely itching for the results and didn't want to wait another month to hear about them. I, Chris Werner, hereby personally express my deepest apologies for keeping you in limbo, as well as making you go back to skim through last issue's story. (As an expression of my gratitude for your patience, allow me to at least save you the time of looking at the table of contents: the story begins on page 58. If you can't find the previous issue, check the bathroom.)
Drafting multi-part story series also creates more work for an author because it necessitates writing a recap of past story segments; it's a bit of a mental chore to compose the same thing slightly differently each time. So here's the same recap from last month, with a subtle change or two that the detail-oriented reader might pick out. The May 2009 issue featured an introduction to the project along with a GM LS7 clutch and B&M shifter swap, and this was followed with CARB-legal K&N intake and Edelbrock exhaust upgrades (July 2009) purple monkey dishwasher. In last November's issue, a full corner-carving suspension treatment complete with Spohn hard parts, AFCO shocks, and aggressive Nitto rubber was had. Penultimately, the January 2010 issue showcased a totally awesome, badass AFR cylinder head/GM LS6 cam and intake manifold swap. This was, of course, followed by the first half of the turbo system install last issue, bringing us to the present day.
The installation of this kit represents the capstone for what has been a 50-state emissions-legal build in keeping with the strict emissions-related requirements of the California EPA's Air Resources Board. Today we answer the question of how much power can be had from an LS1 while staying within the bounds of the most comprehensive pollution-curbing regulations in the land, and since things would start to get dirty were we to try and feed our mill a heftier diet of unpressurized atmosphere (i.e., remain naturally aspirated), there is no arguing that forced induction must be involved in any such quest.
We mentioned last time that while the installation of an STS remote-mount turbocharger system is a straightforward affair, there are a lot of bits and pieces involved; it's just the nature of the beast. As you probably noticed, little modification is needed to the stock exhaust system. But the kit requires a good amount of intake pipe running from the turbo in the rear, to the intercooler up front, and finally to the engine. (Worried that that's a lot of tubing to pressurize? STS says its total volume is not that much different from conventional turbo setups, and that the company's systems compress the intake tubing in about 0.05 seconds!) Follow along as we install said piping and remark on some of the other features that set an STS remote-mount turbocharger kit apart. Check out the FAQ page on STS's website for a more comprehensive discussion than is possible here, explaining answers to questions spanning "If water hits the hot turbo, will it crack?" to "Doesn't heat create the velocity in the exhaust gasses to spool the turbo?," and everything in between.
At close of business last...
At close of business last time, we had just finished welding the turbocharger assembly to the stock exhaust's over-axle pipe, right where the OE muffler used to reside. There is no need for a muffler with this system because the turbo does a darn good job of cutting down on excess noise, resulting in a tone not unlike your typical performance exhaust system.
Continuing onward, the turbine...
Continuing onward, the turbine and compressor housing bolts are loosened to allow the turbo's centersection to be clocked so that its oil outlet points straight down. After retightening the bolts, the oil return hose is run over the axle along (and zip-tied to) Pipe 1, which is the intake pipe immediately downstream of the compressor outlet. The oil return hose is then attached to the oil outlet's brass fitting as shown; note that the stainless oil supply hose can't be connected quite yet. Also at this time, the V-clamp on the turbo exhaust outlet is tightened.
Time to start running the...
Time to start running the rest of the piping that will carry pressurized air toward the front of the car. Two sturdy black plates with threaded holes are inserted into gaps in the subframe and lined up with existing holes; these will help secure Pipe 3, which the author is seen test fitting here (this pipe doubles as the driver-side subframe connector; wasn't it strange when we only installed a passenger side connector back in the November '09 issue?). Getting the pipe completely in position requires some tweaking of the factory body seam you see hanging just to the left of the pipe. After doing so, the rear driver side lift point is repositioned and the front LCA bolt disconnected.
Pipe 3 is first held with...
Pipe 3 is first held with the factory "wavy plate" bolts. The LCA bolt goes in to help locate the pipe, and a screw jack comes in handy as well. Thankfully, there are not one, but two, forward mounting holes for Pipe 3, so one of them can be used as a pry point to get the other lined up (shown). Even after this, the heavy plate inserted inside the subframe likely won't be fully lined up, so more fun is in store. Patience! Once Pipe 3 is in, we reposition the rear lift point back ahead of the LCA, as it is pretty much the safest place to lift from.
This so-called "8mm bolt with...
This so-called "8mm bolt with wire attached" gets inserted into the subframe and, via careful manipulation grasping the end of the wire, it is positioned sticking out of an existing hole that would be impossible to access via human hands alone. Nifty huh? It will be used to help hold Pipe 2 in place.
Getting a 2.25x3-inch silicone...
Getting a 2.25x3-inch silicone coupler onto the inlet of Pipe 3 proved to be a challenge, thanks to tight clearances between Pipe 3 and the factory body seam. (And no, it can't be put on before the pipe is up, smart guy - we tried that). The solution turned out to be jamming a sturdy pry bar between the body seam and the pipe, after which Pipe 2 can slide into this coupler as shown. Its other end (which we find could have used a bit more length) goes to another silicone coupler that is placed on the end of Pipe 1. A nut and lockwasher/fender washer are then tightened onto the aforementioned "8mm bolt with wire attached" you see sticking through the frame here, just to the left of the fuel filter.
Pipe 4, which negotiates the...
Pipe 4, which negotiates the precarious space below the front subframe, goes on the front of Pipe 3. Its bracket is held by the lower A-arm nut. Since the tightening site of this nut affects wheel alignment (the stud it attaches to sits in a slot), its position needs to be marked before removal. With Pipe 4's bracket in place, a pry bar is used to help line the A-arm back up, and the nut re-tightened.
The STS blowoff valve (a.k.a....
The STS blowoff valve (a.k.a. BOV, red anodized) is installed into Pipe IC1 (the IC stands for intercooler), which is then put in place using a hanger onto one of the passenger-side anti-roll bar bracket bolts. On non-intercooled systems, this pipe would be replaced with one that simply heads up to the engine. To get everything properly aligned, we end up having to egg out the hole in Pipe 4's bracket, allowing the outlet of Pipe 4 to move toward the passenger side a bit. The BOV reference hose, which will give a signal for when the throttle has closed and the system needs to depressurize, is then routed down from up top and connected to the fitting on the BOV.
Time to mount the intercooler,...
Time to mount the intercooler, which is recommended for best performance with all STS Turbo kits, and is basically mandatory on systems running over 7 psi of boost. The front clip is taken off along with the air dam; STS provides a good diagram of exactly which bolts need to be removed to accomplish this. Most are underneath, but there are five plastic clips underhood as well. The black, foam bumper cover (visible here just behind the front clip) comes off via five plastic pop rivets; it will not be going back on as it sits right where the intercooler needs to be.