When I was originally planning Project Super VIII, my intention was to keep it on the stock turbo and push it to its maximum horsepower output. However, if you're a regular reader of this magazine, you know things never go as planned. The last time the Evo saw a dyno was when it received intake and exhaust bolt-ons and a retune.
The peak numbers were 273 whp and 288 lb-ft-not great. Mike Welch at Road Race Engineering said this motor might be a little fatigued, hence the low numbers. He also mentioned that it was showing high knock counts, more so than other similarly modified Evos he's seen.
Perhaps my gamble of buying a high-mileage but completely stock Evo hadn't paid off. I was hoping that since it had been kept 100 percent stock, the motor had lived an easy life, but maybe I was wrong. So when you're not happy with the output of your turbocharged four-cylinder, what do you do? You upgrade the turbo and hope it all holds together.
Since I'd be running the car on 91-octane California pump gas, going with a large-frame turbo was out of the question and wouldn't make any sense. Sure, a big turbo could push 30-plus psi without sneezing, but what good is it when the gas that's being injected can't handle it? I needed a turbo that would flow significantly better, with stocklike spool characteristics, and it needed to fit the Tomei exhaust parts without modification.
Let me introduce you to the CBRD BBK Lite. This turbo starts life as a factory Evo IX turbocharger. CBRD machines the compressor cover to accept a new, larger, billet forger impeller wheel, and then it receives upgraded internals, machining, and a complete balance of the CHRA assembly. The end result is a 100 percent bolt-on, stock-appearing turbo with improved flow capability. CBRD has made well over 400 whp on this turbo on pump gas.
I wouldn't net nearly close to those numbers because, as I mentioned, California 91-octane gas is pretty much the worst in the country-basically piss water for an engine.
Since I'm running an VIII turbo, I needed to purchase an OEM Evo IX turbo outlet pipe and coolant hard pipes, as the compressor cover on the Evo IX turbo is larger in diameter than the Evo VIII. If you're replacing a IX turbo, then you're already good to go.
Installing this snail isn't difficult; anyone with decent mechanical skills should give it a try. Heck, if you're completely clueless, buy your mechanically inclined friends some beers and have 'em show you the ropes. Since everything is OEM spec, there's no need for custom work. Bolt in and go!
With the CBRD Lite in place, a visit back to Road Race Engineering was a must. If you're in the lower California region, then there's no one better at tuning Evos than RRE. It's a great (and relieving) feeling to have complete confidence in your tuner, and that's what RRE delivers. Not to mention that Mike is great at communicating exactly what is going on during the tuning.
That's where I was able to find out that despite the CBRD Lite boosting power output by almost 70 whp, my engine is tired. It's late to spool the turbo and still has high knock counts anytime more aggressive timing is thrown at it. Looks like a rebuild is in order in the not so distant future.
But let's forget about peak numbers and concentrate on the improvement in the powerband. I chose the CBRD Lite because it provided a serious bump in horsepower and torque and only lost about 300 rpm in spool compared with its stock counterpart, which, since it's an Evo VIII turbo, is actually smaller. The Lite will spool as quick or even sooner than a stock IX turbo.
The final peak dyno numbers came in at 339 whp and 323 lb-ft of torque at a mere 23 psi. You could normally run a CBRD Lite safely at 28 psi, but not with this engine and gas. We thought about making a glory run and seeing its true potential, but I wanted to keep this motor in one piece, so common sense won out.
On the street, the CBRD Lite is awesome. Its fast spool-up provides loads of mid-range torque, and unlike the stock VIII turbo that starts wheezing at redline, the Lite just keeps providing ample amounts of jam. Furthermore, it's a great everyday turbo; it doesn't surge or require an aggressive driving style to get around in everyday traffic. The Evo's character isn't lost with this turbo, as it remains the same animal it was before but with plenty more oomph on tap.
How does it fair on the track? Well you'll have to wait for the next installment to find out as I head to Buttonwillow raceway to see what this car is capable of.