XR-1.7 | Ali Allage (SPT) - Online Marketer, Serial Entrepreneur, Writer, Automotive Enthusiast, Web Developer

Mar 25th, 09

Lancer Evolution 8.5 Part I – Engine Build and Turbo

Whenever you are looking to build a monster of a car, you have to start with the heart. The heart is the center of any project build and in our case our heart is a 2.2 liter balance of performance and reliability. More specifically, a GSC Power-Division 2.2L XR-1.7 4G63T short block. Thanks to Westboro Mitsubishi, we were able to obtain a brand new 4G63 MIVEC motor to hand over to the master mind behind GSC’s XR-1.7 motor package, Greg Caloudas, to begin over evolution of 8 to 8.5.

GSC’s motor package isn’t a basic bolt on power upgrade. This is a complete package offered to serious owner’s looking to get the most out of the 4G63 without compromises. Specific features include:

New Mitsubishi OEM 4G63 Short Block and piston squirters.
Power-Division 4340 Billet Crankshaft (31 pounds, 94mm Stroke) knife edged and balanced
Power-Division Custom Forged I-Beam Connecting Rods for 1.7 Rod Ratio
CP Pistons 85.5mm Bore, 9310 Wrist Pins, (10.0:1, 9.5:1, 8.5:1 Compression). We went with 9:5:1.
Clevite Tri Metal Main Rod and Thrust Bearings
Power-Division Race Balance Shaft kit
Power-Division Race Main Stud Kit

A nice drool list for a bottom end, which means we couldn’t skimp out on the head. Starting off with a stock Evolution 9 MIVEC head, we added GSC’s S2 cams and a complete valve train upgrade from Supertech. A conservative head for a great motor build.

With the motor sorted out, it was time to match a new turbo kit with the performance capability of the XR-1.7. Cue in Boost Logic’s SC 61 turbo kit. Boost Logic is new to the Evolution world, but have a big reputation for making gobs of power in the Supra market. Their SC 61 turbo kit shows right away the proof in the power making pudding, especially with features that compare to what the more expensive kits have for less money. Features include:

Ceramic Heat Coated SS304 Tubular Manifold w/ true merge collector(1/2″ Thick flanges)
Tial 44mm Wastegate
SS304 Dump Tube
PTE SC50 T04E DBB Turbo w/ vband outlet
Boost Logic Water Line Kit(assembled with Aeroquip pushlock fittings)
3″ SS304 Vband Downpipe
3″ SS304 Vband Midpipe w/ flex joint(Bolts to stock catalytic converter)
3″ Aluminum Intake Pipe 3″ K&N Filter
2.5″ Mandrel Bent Aluminum Intercooler Pipe
3 Ply Silicone Hoses and SS Hose Clamps
Boost Logic Oil Feed and Return Kit(Assembled with high quality SS line and AN fittings)
All nuts and bolts needed for installation
10″ High Flow Fan

Installation of the entire setup was complex and will require professional help. With our lack of wrenching skills we opted to go with pros to get everything installed correctly. Atlantic Motorsports was the shop we went with to get the final installation done. Being a MIVEC conversion, we had to grab a spare Evolution 9 main harness (engine harness) in order to get it all plugged up with our AEM EMS (we had to purchase a new unit to control MIVEC). The conversion isn’t rocket science but does require a large portion of time to make sure all the details are taken care of.

With the basic installation out of the way, the proper motor break-in procedure needed to be performed: 2 heat cycles, then an oil change, then a low boost break-in, 200 miles of driving, and finally another oil change. Atlantic Motorsports then put their focus on tuning the beast. With a few clicks on the laptop and a ton of dyno pulls, the car was ready for action. Final Power Output: 498 whp & 399.3 ft-lb @ 23psi.

Street Test
Of course street testing is fairly limited when testing peak performance. Our intentions for this test was to bring out any reliability issues, lower rpm performance issues, or anything else worth mentioning that impact everyday use. After our 3 days of street testing, a couple of items did come up:

Noticeable turbo lag with larger turbo vs. stock. Full boost came on closer to 4,000 rpm. The motor definitely helped reduce turbo lag, but when you are using a larger turbo, lag is a common issue that is difficult to combat. A smaller turbo will definitely cure this issue, which Boost Logic can provide within their SC 50 kit.
Maintaining speed limit and traction under boost. The power is tremendous enough to break loose the tires, which requires a bit of driving skill to keep under control.
With the S2 cams, idle is a little rough but tolerable. More time spent on the tune could smooth things out more.

With this amount of power at our control, the thought of being able to over take anything on the road was empowering.

Track Test
Our favorite place to test. On track, we were able to start pushing the envelope of power to see how fast this new package was. With a set of Nitto NT-01’s mounted and at full temp, we loosened the leash and hammered down the throttle. At full throttle the car pushed our stomachs towards the back of our brains as we reached our 8,000 rpm limit. Going through each gear, the once mild manor Evolution 8 was no more. Full attention was needed to keep the car inline with counter steer and throttle input. This beast was serious and we needed to respect it. Entry and apex of each turn proved to be easy compared to the exit. As soon as throttle was introduced into the party, the dam breaking surge of power would be too much for the level of grip and our abilities as drivers. On long straight-aways the immense power propelled the Evo into supercar like state of top speed uncovering issues within our aero package (we had none!). Realizing the insanity of the situation, the most logical step would have been to dial back boost and possibly switch to a smaller turbo size. With each lap clicking by, the once logical idea slowly slipped further out of memoryville.

Our track day ended with grin’s on our faces, bbq’d front abs sensors, blown rear shocks, and an appreciation for having a chance to drive such a car on track.

Conclusion
Did we have to do this modification? No. Was it worth it? Yes! The XR-1.7 engine package is a phenomenal modification through and through. We have logged in over 5,000 miles of abuse without fail. With more time spent on the tune and possibly a smaller turbo, the car could be more useable for street and track use. Until then we will continue to suffer with the epic amount of power and god like command of the street and of course, the track.

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