As the Peugeot 208 GTi becomes less expensive to purchase 2nd hand and many have stepped out from the cold into the warm releasing their cars from extended warranty so the number of owners modfying their pride & joy and has increased dramatically. Over the last 5 years Comkotes has been heavily modyfying their own 208 GTi (2013) becoming a test, development, design and parts manufacturer in the process.
Many owners ask about the technical limits on many aspects of these cars so we would like share them here.
Clutches - this all depends how you drive a car although we have had 1st hand experience of mapping 208 GTi's with as little as 6000 miles on the clock and the stock clutch gives up on the dyno when mapping. It does not matter if the clutch is from a by Peugeot sport model, a 208 thp non bps or a 200thp they all give up around the same point. This is torque related and in general from the many cars we have mapped the stock clutch can hold approx 350nm. We have seen evidence the concentric slave cylinder is mainly at fault here being unable to hold the clutch with enough force against the flywheel. Being able to hold 350nm appears to be no problem yet we can quite literally put in another 15nm and the stock clutch gives up. Nowdays its not unusual for these cars to be running 370nm+ on stage 1 map and 400nm~+ on stage 2. There are many clutches available on the market and choosing the right is important. We should point out higher torque the torque level the clutch is required to hold the amount of pressure required to depress and release the clutch pedal increases. Boiling brake and clutch fluid can be another issue causing poor clutch engagement. Many owners report groaning clutch or difficulty in changing gear which can be 1 of 2 things. A) The clutch is not spinning yet the flywheel is, as the clutch begins to grap the flywheel when operating the clutch the inertia is being asorbed by both the springs on the clutch plate and the flywheel springs, this produces a groan. B) The concentric slave cylinder (a spring inside a piece of plastic) is failing, these can fail by seizing due to heat or get gummed up with oil and debris. the pressure plate design has something to do with this.
Exhaust - Its no secret the stock exhaust manifold has not changed in its design since the 207 gti which has a known restriction of 300hp, simply flowing more than this is nigh on impossible. Some have chosen to port the stock manifold but we thinks its best to throw it away if looking for high 300hp+ figures. Another aspect is the downpipe, In stock form they are quite capable of sub 250hp numbers although things get really hard above this with many switching to 2.5 inch downpipe to help the engine breath. At a certain point 2.5" inches is not enough to flow over 300hp and 3" (76mm) downpipes are used instead.
Injectors - Debated for years the stock injectors on the 200thp and 208thp (also used on the 308 GTi 270 as are the head & valves) have a limit of 300hp, many get 290-295hp with them keeping a safe duty cycle. Its not unusual for these models to run out of fuel between 275-295hp as evidenced on the dyno.
Gearbox - we have heard of gearboxes letting go around the 340hp mark, evidence for this is thin on the ground since only a handful of these cars with that kind of power truly exist.
A quick rundown of many mini engined big builds posted over the years or our own 208 GTi build list its easy for owners to see that most of us use big valve heads, large injectors & custom manifolds to achieve 300hp+. Our own development car is built for 350hp. The reason for this was many within the mini world decided to wedge or sleeve their engine blocks for numbers over 300hp, from research a forum member of a N18 mini engine decided to do this and that became a known standard modification to make. We have not found any issues yet due to core shift including cylinder walls moving on cars around the 320hp mark which are not sleeved, some did not even have the bores skimmed relying on the stock castings as they came from factory. GTi's above this power level are still very rare although the momentum is growing daily as many are finding out for themselves what the limits of the stock injectors and manifold is. It was even quoted in 2016 just a handful of mini's are 400hp+
There are many ways to look at build lists along with photos of engine bays using the above information to determine if the car in question is truly running the power level quoted. We always suggest before building some crazy 270hp+ engine owners seek professional advice some of which I hope we have pointed out in this post.
