Project Focus SVT Part III

If editorial stupidity tends to stick in your mind, you probably remember the very specific goal we set for our SVT Focus. Drunk with one too many project car successes, we decided we should try to make our Focus outperform the SVT Cobra Mustang in all our standard performance tests, while keeping the total project bill less than the cost of a Cobra.

Yeah, yeah, we're idiots.
With the stock SVT outbraking and outrunning the Cobra through the slalom, we mostly needed a whole lot more power and a bit more skidpad grip. Last month, we started down the road to power by trying to adapt Performance Turbo and Engine's base ZX3 turbo kit to our SVT. We ran into several snags, all of which we've now solved.

First, we should point out that our kit isn't quite the standard base kit. When we mentioned to PTE that we wanted to beat a Cobra, they slipped a bigger turbo, intercooler and injectors into our kit. Last time we said we were using a Garrett GT28R turbo. Turns out we aren't. The GT28R is good for about 250 hp at the wheels. The GT2871R we actually have is good for close to 400 hp. This is actually the same as the GT28RS Disco Potato turbo in our Silvia (good for about 350 hp) with a bigger, 71mm compressor wheel. The Potato's compressor is 60mm. This means more lag, along with more power potential. Our kit also came with 42 lb/hr (440 cc/min) injectors and an intercooler that's so big, it hangs out under the bumper.

There were three fabrication hurdles and some tuning left to be done after our last installment. Here's where we stand.

GT Fabrications whipped up this gorgeous downpipe that smoothly merges wastage and turbine flow into one happy 2.5-inch exhaust pipe. They also built a second section that goes up, over the cross member to connect to the stock flex joint. We had hoped to use the stock catalytic converter here, but it simply wouldn't fit with the turbo. We'll be adding one downstream of the flex joint soon.

The downpipe
Despite the 400-hp turbo, the kit still came with a laughably small 2.25-inch downpipe and with a flat exhaust flange restricting wastegate flow. When the wastegate is open (which is any time you're making big power) exhaust from the wastegate would slam into that flange, turn 90 degrees, run into the main exhaust flow from the turbine, and turn 90 degrees again to squeeze down the pipe. All this slamming and turning causes backpressure, and backpressure after a turbo is really bad stuff.

Besides, the downpipe designed to fit the ZX3 just didn't fit the SVT.We towed the car over to GT Fabrications in Buena Park, Calif., and asked the guys there to fabricate a downpipe that separates the turbine and wastegate flows until they can be merged smoothly. We also wanted the downpipe to connect to the stock SVT catalytic converter, since it's designed for exceptionally high flow and could probably handle quite a bit of power before it became a serious bottleneck.

Unfortunately, the stock cat was too close to the turbine, so there was no way to connect them. On the bright side, GT Fabrications whipped up a stunning, high-flow downpipe, even including a divider wall that sticks into the turbine housing to keep the two exhaust flows from interfering with each other from the beginning. We had them run the 2.5-inch downpipe to the stock 2.5-inch flex joint for factory reliability and just hooked up the stock exhaust for now.

You'll notice this setup doesn't include a cat at all. The plan is to add a high-flow cat just after the flex joint, but for now we just feel like really bad people.

Installing the downpipe is not trivial, with very little wrench room, but it does come on and off.