Going to 17" tires is a good idea from a performance view because it broadens your selection of available high performance tires and the reduced side wall width which helps bump up the performance of your car even though the 50 series tires which is an upgrade from the 55 series tires that were on the 4th gen Prelude are pretty close to optimum on your car.Unfortunately reducing your side wall width, will slightly reduce your ride quality and increase the chance of damaging your rim from impacts along the road.
I would not advise lowering your car for the following reasons.
1: The car has already been lowered 2" relative to the original Prelude and 1.2" relative to the 4th gen Prelude. Bottoming out and taken impacts on the road does not make for a comfortable ride.
2:People who lower their cars reduced their cars tendency to bottom out and hit things by installing stiffer springs.Of coarse the stiffer springs reduce the ride quality by having the driver feel each bump hit on the road raised to the second power and cause this strange fore and aft oscillation type motion each time they hit a bump or when accelerating hard which also degrades the ride quality and sometimes looks comical.
Your Prelude's suspension has been thru several revisions as shown in the press release below with the goal of providing Superior braking , cornering and ride compliance. When you install new springs all that engineering work goes out the window.
From a 5th gen Honda press release:
FRONT SUSPENSION
The double wishbone suspension system used on the front of the Prelude has undergone several revisions intended to enhance its stability under braking, its linearity when cornering and ride compliance. The elasticity and resilience of the elastomeric bushing in the end of the leading link has been revised. The bushing functions as a shock absorber for harsh impact energy (the kind that would be transmitted to the suspension if a tire hit a sharp ridge in the pavement). The new material is stiffer, and eliminates any brake judder or shimmy that might occur under heavy braking.
Previously, the pickup points for the upper A-arm were anchored to the body with a ball joint on the body side and brackets on the end of the A-arms straddling the ball joint. The new mounting is similar to the one introduced on the 1996 Civic. The end of the A-arm is hinged in a broad-based bracket (two per arm) attached to the body. The new bracket distributes force over a wider area, and is very resistant to flex and camber, caster and toe distortion.
The Prelude front suspension also has a relatively low roll center: 2.2 inches (58 mm) above the ground. This helps minimize any suspension-jacking effect and track (width) changes. Minimizing suspension jacking improves steering feel and linearity when cornering, and minimizing track changes reduces road sensitivity and tire friction from side forces when traveling over uneven surfaces. When cornering, the inner wheel also remains closer to perpendicular (relative to the ground plane) throughout a greater range of travel, which improves tire adhesion. A hollow 1-inch-diameter stabilizer bar helps minimize body roll.
FYI:Link to the design of the 1st double wishbone suspension used on a Prelude which is the core of the design of the front suspension of 5th gen Prelude in my opinion and demonstrates the extreme level of engineering that goes into their cars thats hard to beat in an overall sense.
http://bluegreenlabs.com/Prelude/3178_001.pdf
Linear Mode
