Daily Archives: September 13, 2020

Nothing much new

I’ve been doing some figuring on the intake manifold and cam combination, but TBH this one is not well covered in the public literature and simulations. Except for the Holdener videos this is pretty much terra incognita for published data. And not to be tooting my own horn, one of the things I was really good at was drawing correct conclusions from insufficient data. And right now I’m dealing with way too little data, essentially only 5 data points between the Holdener videos and two other TPI videos, and those two went with the commonly accepted practice of short duration cams with the long runner intakes. Like 240° advertised duration or less short. My theory hypothesis is 270°@0.050″ lift at a minimum and 290°@0.050 preferred, those are considered radical durations that would have terrible idle and low RPM manners if not for the stupid long runners, but even so would not work without the large cross-sectional area of those long runners giving good airflow for the upper RPM ranges.

On other things I’m putting out an ad for someone to make my car work as DLC for GT5 so I can drive it on the gokart tracks I built with the track editor in the game. Translating that to English I’m asking for someone to code the Sprint-T as Down Loadable Content for Gran Turismo 5, so I could make it usable in the game. I could use the free classifieds in Grassroots Motorsports to request submissions. The thing is I have zero idea of what information would be needed for the game version of the Sprint-T. I know the tuning choices give 3 selections each from 3 categories of tire, and some cars have the option for tuning the power output from the engine, to that means a variable with a range for power and also variables for grip and hydroplane resistance in the tires. Now how sophisticated the tire modelling is??? it could be as simple as a simple ratio for grip that is dependent on tire choice or a multi-variable algorithm that takes temperature and depth of standing water along with a bunch of other things into consideration. And there’s nothing I can find on the internet about it. I can find some of what has to be simulated in this formula “Pacejka Magic Formula” Physics Doctorial thesis on the web and simplified formulas for designers and in video format Brian Beckman: The Physics in Games- Real Time Simulation Explained. The biggest thing is the physical limitations of the CPU and GPU as the formulas get to various limits that end up dividing by very small numbers and the answers get larger than the registers in the CPU or GPU. Which has nothing to do with how GT5 stores its car models, just a taste of what’s involved in building that model. And after all that I still don’t know how to get from the piles of parts distributed around the house to driving pixels on my TV screen, which is why I’m thinking about paying someone to do it for me.

And I just face-planted in the keyboard because I’m glazing over at the programming details that don’t apply to this situation, so this is a good place to put this to bed and me shortly after.