Re: [VintageLambo] Re: Jalpa Twin Turbo Project

Hi Laust, I always enjoy reading your writeups - you could also qualify as a damned good tech writer (add that to the resume ;-) ). I read your web site right after you had posted the results of the Espada project and as I remember, you can go six degrees with no penalties and an increase in low end torque. How many "holes" is that in the drilled sprocket? One? I considered trying that when I rebuilt my engine but I got a case of the cowardlies. Anyhow, it is great to have your inputs to the site - many thanks. Jack lgpdk wrote: Hi Fred and Jack, Thanks for the encouraging words and trust in my abilities. The 3 pictures are uploaded to a separate folder titled "Jalpa Twin Turbo" (although only part of the title shows up on my computer). I think it is a good idea to keep this in a folder separate from the regular car photos. That way I can also upload more pictures to the same location in the future. To Fred"s specific questions, yes I am formally a mechanical engineer with a thesis in Underwater Non-Linear Acoustics (just to make my life as difficult as possible), but have taken a number of courses for electrical engineers. As you know they have specialties and sub-specialties as well such as Digital/Analog engineers, various chip design technologies, systems designers, etc. I can handle simple circuit designs and have professionally done some system architecture design in the area of Diagnostic Ultrasound Imaging, additionally I have done some code writing (programming) and performed various simulations. I have taken theoretical courses in fluid mechanics, thermodynamics, journal bearing design, metallurgy… Ups, I think I am showing off now. I have a resume on my web-site in case you wish to probe further. In my opinion most of the engine designs from the big auto manufacturers reflect their internal hierarchy, where each engineer (or subcontractor) gets and defends their narrow task in which case the systems approach and technological progress suffers. As examples, only now are they looking at integrating the starter motor and alternator into one unit in place of the flywheel. By proper electronic control it can then be used as a torsional vibration dampener and power booster (small parallel hybrid engine). BMW is now designing their engines with fully variable valves (timing and lift). Direct fuel injection (into the combustion chambers) and gasoline compression ignition (knocking is eliminated by excessive EGR) are other obvious beneficial technologies. There is very little up front analysis in my project. Most designs, and certainly this one, starts with some specific and vague declared goals, such as 350WHP, flat torque, impressive looks, simple upgradeability, optimum serviceability and reliability. The challenge is to reduce this into very practical terms that can be easily communicated to (in my case) mechanics and welders. For that purpose I am extensively using SolidWorks, a very impressive CAD package for personal computers. When I am ready, I will show those pictures as well. I have also bought a combination Lathe/Mill (yet to be installed) to make a few components myself. We have run the design through an engine simulation "Engine Analyzer" (http://www.performancetrends.com) and with 14 psi boost it returned 450HP, but with high knock index. The real effort to accomplish that lies in the details, which, if not found and properly taken care off, each will make the car less drivable. Just two of many examples: the torque curve depends on the intake runner length, which through resonance gives better filling (volumetric efficiency) at a specific RPM range. The cross connection of the runners (for vacuum sensing and balancing) has to be heavily restricted in order not to affect the resonance. Very similar to how the pitch is changed in a flute. Another is an unwanted resonance in the fuel rails a