great video st-anger! i think the hockenheim footage was great! and a very impressive NS time indeed... tho i must admit, i dont know much about tire ratings... i would've thought it would be a lot faster then an M3
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I guess what I am asking is there a way to safely run higher boost pressures and not sacrifice reliability?
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i think ill have a go at this...
often, to increase reliability, charged engines run on lower compression ratios. with a lower compression, there is less direct stress on the internals. also, using lower compression, i think lower torque values would occur overall... cirtainly off set by the compressed air.
as st-anger was mentioning, a turbo would have to spin at much sustained higher velocities, further increasing heat in the turbo charger through friction with itself primarily. often aftermarket tuning will run larger turbos runing lower rpm's for the same mb levels at the sacrifice of lag vs. higher power ratings... albiet turbocharging technology has come a long way to reduce lag times in a variety of ways... i think vovlo had a variable compression ratio in one of thier inline 5 turbo motors... higher compression at low rpm for increased torque, and throttle responce, and lower compression once boost is built up.
it is my understanding that flow charactaristics in most production intercoolers are not designed for much higher then stock ratings, particularly for prolonged use. 'heat soak' is less noticiable at lower densities, and flow rates... but the intercoolers' rate of thermal reduction is reduced by things such as internal low pressure zones, and low fluid flow areas... think of it somehwat like a vortex that gets larger with more pressure, and more heat that reduces the efficiency of the whole.
all to often, aftermarket supercharging kits in particular advertise 'bolt on' when really, this is far from the best option... but this is also true of turbocharging as well. when increasing the air density, inherently heat will occur... added heat, added pressure... which then leads away from an optimum burn, and runing extra rich. this also makes sence when comparing engine re-mapping to turn up the boost with otherwise stock configurations.
eventually, turning the boost up beyond injector, fuel pump, and pressure regulator capacity would cause extream lean burns, and damage the tops of cylinders and heads along with power losses...