Hi Chris,
First of all what an awesome car you have! It would be nice to get an S8C on it
That aside the S8C will at least give you 8 times the data of the M800 but it also comes with many more engine parameters to log, especially if you are still developing the engine package, so the overall gain is perhaps not so big. If you want to log the GPS info for track mapping it is possible but at the moment it's a bit of cludge (IMHO) as you have to assign it as an analogue input to two channels, and then assign these two channels appropriately as long and lat in the data analysis tool.
However if you want to look at all your data in one place, then you should be looking at firing all your relavent data to a datalogger using CANBUS and then you have the freedom to pretty much what you like. So even using a GPS equiped logger isn't out of the question. There are a few loggers that fit the bill for you, including products from AIM Sports, GEMS, Race Technology, Racelogic to name but a few. This give you the option of logging plenty of more engine specific stuff on the S8 and not cluttering up your track data with all of that too.
You can use a Racelogic GPS speed box to output GPS velocity as a 5th speed input into the S8 which will allow you to do some nice things, including accurate track mapping with the addition of a Lateral G sensor, but if you want to be able to look at racing lines on individual laps and compare then with video info, lap time etc, then there are probably better products to use that use a 10Hz GPS setup.
