A week with no mufflers... will it drive right?

TomCat said:

Anyways, as far as backpressure for power... you need it! The car feels like it has lost half of its low end torque.QUOTE]

So, you hooked up a backpressure gauge and your backpressure dropped? I bet if you did, you would see more backpressure and erradic flow.

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90mustangGT said:

Camman - Really, do you know how engine's work? You are one stupid SOB. They are refering to velosity. Mass, volume, and velosity. It's a lot more complex than that. So, according to these books you have read, what is an acceptable amount of backpressure, such as at idle, cruising? One pulse of the exaust on one runner pulling the exaust out of the other runner. So how does exaust pressure backed up into the engine help it run? I bet you dont' know the answer. What is the actual mass of air? The idea of an exaust system is to get the gas out of the engine, not to keep it in. Different sizes of tubing, different lengths, and even the shapes contribute to the way it performs, as well as how it was designed to remove the exaust gas from the engine. The factory designed the exuast systems with the smog test in mind and cost, not performance. What do you do for a living? Me, automotive technician, two years of trade school, seven on the job, my certifications include X1 - exaust systems and A8 - engine performance, among others but those areas include backpressure as some of the subject matter. Have you ever hooked up a backpressure gauge to an exaust system. If you want to come making insults to me. Short bus, call me a stupid, really. Prove it.

Here are some eye opening threads about exaust systems:
http://bbs.hardcore50.com/vbulletin/showthread.php?t=30103
Those are some guys that actually know what they are talking about, a lot mroe than me and most people.
Linked from that:
http://www.popularhotrodding.com/enginemasters/articles/hardcore/0505em_exh/index.html

Now that is a artical worth reading. Everyone should read that artical.

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With muffler flow requirements out of the way we can move on to methods of applying suitable capacity mufflers to the “system” without needless disruption of length-induced pressure wave tuning. Probably the best way to ease into this somewhat complex subject is to consider some of the published muffler test results done in recent years. These tests appeared to have shown that, sometimes, lower flow mufflers inducing at least some backpressure were required to make best power. In all such tests that I have studied, the conclusions (as apposed to the tests) were invalid. There turns out to be several reasons for this and all are relevant to building a near zero-loss exhaust system.

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The first point canceling the supposed validity of back-to-back test results is due to the varied internal designs seen amongst the test pieces Fig. 8. Many mufflers are made up of a number of inter-connected chambers having varying degrees of access ease by the exhaust. Others are of the “glass pack” variety. These types represent opposite ends of a spectrum and have a substantially differing response to arriving pressure waves.

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