Turbocharging the 4G64
Preface
Let's start with the basic theory behind this transformation. Spyder GS owners were cursed with a motor different from every other Eclipse on the road... the 4G64. If you go looking for performance parts for the Spyder GS, you will likely find NONE. While at first this seems like a horrible situation, it turns out to be a happy ending. The 4G64 is nearly identical to the 4G63 in many respects. Thus, many of the performance parts made for the Eclipse turbo will fit the Spyder GS as well.
BEWARE: Often performance shops will list parts for sale with simply "Non-Turbo Eclipse" listed as a description of the car it will fit. These parts will most likely NOT WORK on the Spyder GS, since they were likely designed for the non-turbo 420a Chrysler engine.
To gain the extra .4l displacement, the 4G64 has a very slightly larger bore (4G63 is 3.347" (85.0mm), 4G64 is 3.4055"(86.5mm)), but more importantly, a much longer stroke (4G63 is 3.46" (88mm), while the 4G64 is 3.94"(100mm)). However, the 4G64 shares the same rods with the 2G 4G63T. Thus, the deck on the 4G64 is 6mm higher to compensate for the longer stroke. This is the major difference in the block. A deeper stroke means less balance at higher rpms. The 4g63 has a close ratio between bore and stroke meaning higher revs without damage. However, the 4G64 will produce more torque at the same RPM.
Since the exhaust manifold of the 4G63T has the same bolt pattern as the 4G64, there is a very easy and cost effective way to add a turbo to your existing car.... Buy a used exhaust manifold & other parts, and bolt everything on!
Warning:
Turbo charging or any other vehicle modifications can result in
personal injury, severe engine damage, or vehicle damage if not done properly.
Please use this web page as a guide only. I do not and will not assume any
responsibility for damage that may occur to you, your car, or anything else.