McLarren Mercedes SLR

Kids! Do your homework!

Rightfully it is considered the GT of supercars. But it is massively flawed by the current philosophy which guides the latest Mercedes designs. Like most of the top brands Mercedes is trying to have performance cars with all the commodities. Unfortunately it looks that their engine team didn’t finished the same universities as the one from BMW, Porsche etc. Therefore they had embraced a less sophisticated way, larger displacement and brute supercharging in order to achieve high performance levels. To an already big engine, at least for V 8’s, 5.5 liters they added a supercharger to raise the numbers to 600+ HP and a useless 800 Nm. It is not that bad but few knows that the charger by itself is eating 100+ HP only for himself. Ok, this is happening only when it is engaged; the engineers knew that you don’t need that power all the time. Still, no points for the design finesse.

How would I do it?

Of course I would start with two turbochargers. But what about the turbo lag? Because the guys from Mercedes have some experience with superchargers it would be a pity to lose it. So why not take a smaller supercharger like the IHI form the AMG 32 engine. It will help the engine up to around 3500 rpm where the turbos will be alive and kicking, ready to take the job. From here you will have the same power will no parasitic loses. Another thing that is just adding weight to the car is the water cooled intercooler. Because you have a two step cooling process (ambient air -> water -> compressed air) the final temperature of the charge will be higher. Some say that there are more parasitic loses in an air to air intercooler because the compressed air path is longer. I just can say that:

• There is a lot of space under the SLR bonnet, and the lateral air fins could do a great job to dump the heat from the intercooler.
• The air to air intercoolers form Porsche 911 Turbo and 911 GT2 are doing a great job.

Therefore my suggestion: Dump them!

Another thing that is killing the mechanical finesse of the car is the lack of a proper gearbox. I wanted to say that automatic gearboxes are not for supercars, but Porsche is showing me that I’m wrong, the 5 speed automatic transmission of the Porsche 911 Type 997 Turbo has better performance in terms of dynamics against the 6 speed manual. But I still consider that a sequential, if not a double clutch gearbox is the way to go. To use the argument that the engine has to much torque is not acceptable. Bugatti did it!

By the way, it's that hard to make a proper progressive ceramic disks brake? Everybody else did it. And what's with that cheap plastic central console?