Ah my long suffering civic
Ok well I’ll give you the full story, I've owned the car from new for almost 4yrs and as you might imagine given my field of work it's had all manner of different parts bolted on to it and taken off again in that time.
Although the engine was previously quite modified the only power related modifications now are an enlarged throttle body, an after market and much bigger exhaust B'pipe and a completely re-designed intake manifold separated from the cylinder head by nylon spacer (I was trying out a pressure wave tuning calculation based around the Helmholtz tuning method, it worked!) the last time I checked the car measured just under 190bhp at the hubs on our Rototest chassis dyno.
The chassis it’s self is fitted with stiff engine and gearbox mountings, uprated brakes, a Tein type Flex coilover suspension system and a very experimental front trackrod end solution.
With regards to the chassis dynamics, it was immediately apparent to me that Honda had compromised heavily in the suspension design on the UK EP3 Civic Type-R choosing to run with almost no static geometry at all and using softer linear rate springs than they had chosen for the Jap model. They had tried to address the cars intrusive natural under steer departure with the anti-roll bar rates. Whilst this meant the car was very capable at the grip limit in a steady state turn condition on a dry surface, the transient movements (before the anti roll bars loaded) were seriously unnerving and in the wet when you're almost totally unable to load the anti-roll bars the under steer was horrible.
The Tein type Flex kit has much stiffer spring rates which appear to be pretty well developed straight out of the box. Taking a portion of the tyre load control away from the anti-roll bars means that the difference in balance from dry to wet weather is reduced and the car feels much more predictable and linear in response through all transient situations.
After fitting the type Flex and lowering the ride height considerably over that of the standard civic, the car developed an annoying bump steer habit, obviously Honda had built in a “tow out on bump” characteristic to the front suspension which is by design “rising rate” in nature and I was now operating in the top end of that scale. The answer seemed simple, change the height of the TRE in relation to the rack, in reality deciding exactly what height I’d like that “new” height to be has been fairly tricky but I think I’m pretty close now.
I’m by no means finished playing with it yet, at present the car feels very balanced at full throttle but actually quite loose at steady throttle. I want to balance out this aspect next
