Following on from the previous Blog post outlining the reasons the Twin Turbo conversion has been designed and built the way it has, we are now in a position to share some of the first Dyno results of the conversion carried out on the development car!
First and foremost we have to say that this has taken longer than expected, some of our suppliers have been badly affected by the COVID-19 pandemic so we have just had to except this and carry on. We chose the suppliers based on some very strict criteria where quality, performance, accuracy and cost are paramount so we have had to cut them some slack due to the pandemic and adjusting delivery times and expectations due to that.
The car has been in and out of the dyno tuner for almost a month, there has been one issue that meant the car had to come back to us for some mods but on the whole it has gone much smoother that anticipated. We had a target boost pressure in mind but there are so many variables with this sort of thing we spent a bit of time varying the boost level to get a very safe run using pump fuel and luckily we have been getting some very warm weather for the UK these last few weeks so that has been useful for pushing the limits. To cut a long story short we are running between 5 and 6psi peak boost and have absolutely zero detonation and a very nice AFR which gives me no concerns over engine longevity at all. As many of you will know the peak HP numbers are great for gloating at car shows/pubs but in reality a nice power/torque curve make a car fast! That's not to say we are unhappy with the peak numbers, a peak power of 428BHP and peak torque of 430Nm is right where we hoped to be but just have a look at the torque curve on the dyno graph below!!
Another important factor that is a high priority to MRN is boost response, this is both how early the boost builds in the rev range and also the lag that is so often talked about. Now most people that complain about turbo lag remember driving an early 90's turbo car and how bad turbo lag can be, in reality modern turbo design and a properly sized/specified turbo (or two) are not even comparable to those cars. Nevertheless it needs to be covered! Boost build and lag often go hand in hand, a car that starts to make boost at around half max engine speed will probably be a bit laggy but said car is likely to be built for peak power rather than drive-ability. As you can probably work out from the dyno graph above the MRN kit starts making boost at a little over 2000RPM and peak boost is reached just below 3000RPM!! This is honestly a little better that we had calculated/expected but thats fine by us!
We spent a lot of time working out the best option for the turbos for this kit and its one of the most asked questions "what turbos come with the kit". Our standard answer is "they are Genuine Garrett GT roller bearing turbos", sizing a turbo is not rocket science but there is quite a lot involved so we prefer not to give away that information and hope that is understood and no offence is caused.
So just for fun we took the power and torque figures of the stock car that was dyno'd as a baseline prior to fitting our Carbon Plenum kit and made a graph with the results above on it as well. *the figures were manually read from the graphs at 500PRM intervals so please forgive any slight inaccuracy!
So above there is a direct comparison of the same stock car (red traces) and then equipped with the MRN Twin Turbo conversion (Green traces). As you can imagine the car drives superbly and is an absolute pleasure to drive, it really feels like this is the car that Porsche should have made from the factory, and how else can you get into a 400BHP Porsche for this much outlay?
The pricing and availability will follow in the coming weeks but as we have already mentioned on social media the price will be circa £6500, the only extra needed will be engine oil and dyno time.
EDIT:
We have had some requests for a sound clip so......