Ref Peugeot 205 1.6 GTI I am thinking of creating an extra breather pipe using a split in one of my breather hoses (narrower bore - to throttle housing). I believe that this addition would lead to a cleaner breather system. I note that the breather tubes are thick rubber. I have some thinner rubber, and wonder if this will serve. I assume that the thick rubber is only needed to prevent kinks (am I right). My plan is to create a Y piece (at the split) and connect an extra hose to vent excess gas close to the base of the engine. I think it best to create an extra breather rather than leave this split because the gas may accumulate and leak into the cab. I am in doubt about this though since the engine is exposed to the road, and therefore should allow air to circulate and keep the engine compartment clear. The cab also look isolated to me. Let me know what you think Ps. I note two breather pipes to the oil filler cap, and one hose to the body of the filler cap. Can someone explain the breather circulation process.