Quote:
Originally Posted by kees
What applies for N/A engines also applies for turbo engines - but not after the cylinders like on a N/A engine, but after the turbo.
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How? In na engine the whole story is beganing when the exhaust valve is opening exhaust gases are pushed out with some pressure. Right? The vave of that pressure is moving with around sound speed forward. Right? When it is reaching the point where is big difference in cross section (connection with another exhaust pipe) it is changing the direction and as vaccum vave is going backwards (for us is only important the exhaust pipe from another cylinder). And the lengh of pipes needs to be so long that when the vaccum vave reach the exhaust valve port in this cylinder this valve shoud open. Right? After that this vaccum vave is "sucking" the exhaust gases from this cylinder. Thats the very short and extremally basic theory of equal lengh pipes tubular manifolds.
Now tell me how it can work in exhaust after turbine housing when turbo is not giving any pulses (don't tell me that turbine wheel vanes are giving the pulses because at around 70 000 - 130 000 rpm and 7 - 9 vanes it will be around 49 000 - 108 000 super micro pulses per minute, just can't phisycally messure it).
Maybe my experience with Alpina engines is not impressive but I'm working on other engines over 15 years and four cars which I prepared (two Cosworth's, Integra and Fiat 126
) won polish race championship (two overall). I prepared many cars for fast road use too (last time mostly BMW). I'm very, very far from saying that I'm a engine magician, guru or whoever. I'm just the bloke which is working on engines enough long to have some experience and enough skills to not be shamed of it.
No offence at all only wish not mislead other forum members.
Jan