The project started by assessing the
feasibility of turbocharging the MI16.
The major issue was the compression ratio of 10.2:1. This issue was
addressed by using modified pistons, increased cylinder head chamber
volume, and pocketed valve heads and a 1.7mm head gasket. This resulted in
a compression ratio of 8.5:1.
I used my favoured twin 45DCOE's for
induction, coupled with a tubular tuned exhaust manifold and
a Garret T3 0.48 55trim turbocharger. Ignition system is a JME mappable
system incorporating a 3 bar map sensor to enable the ignition curve to be
mapped for positive manifold pressures as well as vacuum, throttle
position, water temperature, and air charge temperature (ACT's).
The MI16 cylinder heads are simply excellent. As std they use 34.7mm inlet valves. The valve seats in the head are however big enough to take 36mm inlets whilst I advise leaving the exhaust valves standard. The head was ported, the valve seats modified, valves reprofiled and of course the ports matched to both manifolds.
Cam selection is similar to a Cosworth
BD14 profile with 262Deg duration and
9mm of lift. Cam timing is achieved by the use of verniers and is different to
standard, essential due to the increased exhaust back pressure
turbocharged engines exhibit.
Intercooling is again achieved via my
NMS Cosworth "special" but has required a smaller radiator in
order to fit the boost hoses around either side of the radiator.
The intended maximum power output is around the 300bhp mark, but has yet to go on the rollers. The car has been mapped and setup live on the road and is currently running 14psi of boost giving around 250bhp.
Suspension consists of coil overs on the front and uprated torsion bars and adjustable dampers on the rear. The car runs discs all round the front being based on a 306Gti6 setup whilst the rear remains std 1.9gti in size.
The latest ongoing development has seen the interior removed and a 6 point cage fitted complete with Kevlar buckets. Now the car is in full working order expect to see it around at Santa Pod and numerous Peugeot meets throughout 2004!
