Recently I noticed there are differences between the factory intake tubes on certain model years and models of GMT800 trucks & SUVs. By intake tube I mean the hard plastic portion between the mass air flow sensor/airbox and the throttle body. It seems like mostly the trucks received a smaller, less bulky intake tube with less passive chambers. Most of the SUV's I've seen have a larger, more complex intake tube with passive chambers added to the intake tract. The larger intake tube goes clear over in front of the alternator, whereas the smaller intake tube goes no further over than the throttle body. Additionally the portion in the middle is larger volume, where it's in front of the throttle body.
Anyone else noticed these differences before and gone down the rabbit hole of why GM had different intake tubes on different vehicles, that all were using the same 5.3 engine LM7? There has to be an engineering reason for the change, but that is above my knowledge base. I know from other vehicles that these passive chambers in the intake tract serve a purpose and are not there without reason. I have an '88 TRX250R that has one such chamber in the intake tube and decades ago someone did the research and found it was added to the intake tube as a spot for a random intake pulse that reverb'd backwards at a particular RPM range to go to without disprupting the intake in-flow.
I suspect these are the same purpose, but what does not make sense is that across multiple vehicles using the same LM7 5.3 engine that all are not given the same intake tube from the factory. Jump on it this rabbit hole, it is cool and dark and deep I suspect.
Anyone else noticed these differences before and gone down the rabbit hole of why GM had different intake tubes on different vehicles, that all were using the same 5.3 engine LM7? There has to be an engineering reason for the change, but that is above my knowledge base. I know from other vehicles that these passive chambers in the intake tract serve a purpose and are not there without reason. I have an '88 TRX250R that has one such chamber in the intake tube and decades ago someone did the research and found it was added to the intake tube as a spot for a random intake pulse that reverb'd backwards at a particular RPM range to go to without disprupting the intake in-flow.
I suspect these are the same purpose, but what does not make sense is that across multiple vehicles using the same LM7 5.3 engine that all are not given the same intake tube from the factory. Jump on it this rabbit hole, it is cool and dark and deep I suspect.
