Steel 911 studs regardless of their alloy DO NOT expand at the same rate as aluminum cylinders and heads. Thats the reason Dilivar was developed, for the later 2.7 liter. Porsche changed the stud material to increase the expansion rate to try and eliminate studs pulling out of the cases which changed drastically due to the hotter engine temperatures from 5 bladed fans and thermal reactors. So, even the factory with all of their German engineers got it wrong with calculations. Thats why we have simulations these days and testing. To find what is not/or very difficult to calculate. This IS one of those calculation dilemas. Dilivar still does not come anywhere near the expansion rate of the aluminum. So there IS a restraining factor in head studs.
Retrofitting motorcycle throttle bodies is an excellent
starting place, The late model Triumphs are FI and have three cylinders. Althought the placement of the injector angle may not be optimum for our type of head, and they are kind of small. It would be cool if he could put together a package that would give a secondary throttle valve and actuator to increase port velocity at lower rpms while enabling a much longer duration camshaft for better top end performance. I would consider TL1000S throttle bodies, plenty in the salvage yards, and 52mm...... yahoo!
Not to get into a pissing contest, but you must realize that temperature has such a great effect and the target temperature the engineers determine, may not be the actual operating temperature. I have seen this with motorcycles, we engineer products and improperly arrive at a result via calculations which can be intuitive, but not always. Shit in, shit out is a common term. As for a direct measurement as to growth at a given temperature, that may be possible, but whos to say that is the temperature achieved. Raby has spent countless hours with the DTM optimizing, and it was designed prior to him taking over the project. So after swirl straighteners and vortex generators (sorry if I don't have the exact changes Jake) he has found the correct combination, through testing. And after all the calculations and all the intuitive figuring, this is what it comes down to: How does it perform in the real world and does it perform as we intended. If not, apply Demmings (drill down) principles and continue refining until it does.
Erik