GenVibe - Community for Pontiac Vibe Enthusiasts

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Did you purchse an entire exhaust or just the muffler? I was thinking of going with a Flowmaster 60 series muffler myself.Jim

You sound dissapointed that you had to put on a Flowmaster! I went with just the 60 series, and I love it. It growls at about 3000 and gets dead quiet when I am at cruising speed! Exactly what I wanted not that ricer coffee can hanging off the end of my litle rat! You will notice it get a little deeper tone as it gets 'broken' in!

Quote, originally posted by engine1 »It growls at about 3000 and gets dead quiet when I am at cruising speed! Noise at cruise is the reason I abandoned the flowmaster idea, because my wife and son have to deal with the noise too. The Flowmaster gets nice and quiet at cruise eh? Mabey the dream is still alive. Has anyone posted sound clips with the 60 series on the vibe?

I'm dead serious I can't hear a difference at all from stock! I used to have a full size Bronco w/ 351M and cherry bombs and no tail pipe. They stopped just behind my seat, the drone would drive me crazy.....so loud! Thats the main reason for choosing the Flowmaster, they have perfected a smooth flowing muffler that increases performance without the drone. I also kept the stock tip, don't know how much diff it makes but i didn't think it needed to be any bigger! Maybe its because I'm 31 and moving a little more quickly to old fartdom! I wish I could get a sound byte for you but alas I lack the resources, but I have convinced a few guys I work with to change from Magnaflow and those other fibreglass muffs!

Quote, originally posted by engine1 »...It growls at about 3000 and gets dead quiet when I am at cruising speed! ...Err..., just to point out the obvious, depending on manual/auto/1zz/2zz, 3,000 RPM is cruise speed for many....

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I meant 3000 in first and second You should try cruising at about 3500 rpm in fifth thats very nice! At one point this summer spent two solid hours at 140km/h never got above 3700 rpm....this car is great! I look forward to the GXP when I trade this in two years from now!

Oh sooooo cool! I've been eyeing up the 60 series for almost a year now. I think I'll have this done over my Christmas break from school. I want to have my resonator removed as well. I don't mind some extra noise, but I also hate that ricey sound. Glad to hear that this muffler does just the opposite.

Keep the res on. You will have much quicker throttle response w/ the back pressure it provides!

Is there any evidence to support this? I have been reading around on this, and it seems that more and more people are saying that reducing the backpressure will enhance the performance rather than hinder it despite the reports that some BP is good for small displacement engines. I'm not sure myself, but it would stand to logic that an engine that flows more freely will be able to produce more power. I'm certainly no expert on this, but can anyone provide some evidence that reducing the BP will harm our car's performance?

Just try this, blow hard through a straw, now through a paper towel tube, which moved the air with the greatest amount of pressure? The internal combustion motor is just a glorified air pump, and you have to have a nearly equal air in/ air out ratio for a motor to work most efficiently. With out forced induction the motor cannot produce enough cfm on the exhaust stroke to maintain smooth torque balance thru the curve. That balance is created with the help of restrictive chambers prior to exiting the tailpipe, just as the air is drawn in, compressed, and forced in to the cylinder, it needs to be forced out of the car. You could change the cat to a high flow performance variety, but I would still maintain the res for power out of the hole!

How about this:Put a clothes pin on your nose. Now, breathing only through a soda straw, see how fast you can run 1/2 a mile. Repeat with a paper towel tube.

MadBill you forget that we can change the size of our cylinders so to speak, or the rate at which we breath; the engine, even with the vvtli cannot! Are there no physicists who can lend some clarity among Vibe owners!

i have a flowmaster muffler with a 2-3" end tip and it is LOUD! on the highway in 6th at 80mph it is DEEP, i love it. One thing though, after 4hrs it gets a litlte bothersome. I think the end tip is 3 now that i think about it. It also might be a ractive.

Quote, originally posted by engine1 »! ...Are there no physicists who can lend some clarity among Vibe owners!Actually, as an automotive engineer and hobbyist for over 30 years, I expounded on the subject of back pressure in a thread here a few months ago. I can pull a dozen or more engine design books and twice as many magazine articles off my shelf, not one of which supports the theory of a four stroke engine "needing" exhaust backpressure. (Gas velocity, e.g. pipe size, especially primary pipe, is a different story, as is the possible need to re-tune a carburetted engine to a new low backpressure system)From simple physics, the work done by the pistons in pushing the exhaust out of the cylinders is in direct proportion to the pressure they work against. Also, the higher the residual pressure, the more burned gas remains in the cylinder, diluting and reducing the fresh charge. The very best race mufflers, e.g. a pair of 4" inlet Flowmasters on a V8, have almost no power loss vs. open pipes at high RPM, and sometimes even slightly improved mid range, but such improvements are from resonance tuning due to their volume, not their minute backpressure.The "some backpressure required" myth is very persistent, but no one who has proposed it has ever been able to back it up to me with a reference source or a shred of evidence!OK, down off the soapbox and on with perusing the posts.

Quote, originally posted by mrgrn »i have a flowmaster muffler with a 2-3" end tip and it is LOUD! on the highway in 6th at 80mph it is DEEP, i love it. Is it a 60 series or another Flowmaster muffler? Also, is this on a Vibe, and if so, base or GT?

Quote, originally posted by MadBill »The "some backpressure required" myth is very persistent, but no one who has proposed it has ever been able to back it up to me with a reference source or a shred of evidence!This is what my main inquiry was about. I have heard the BP theory other places as well. I just thought that it contradicts common sense and all known applications to date. But I was not discrediting the whole idea all together as we discover new things about cars all the time. I figured that it is possible, but it didn't make sense and I was wondering if someone could support the theory with data from experiments or at least in well supported theory.

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Quote, originally posted by Stang2Vibe »This is what my main inquiry was about. I have heard the BP theory other places as well. I just thought that it contradicts common sense and all known applications to date. But I was not discrediting the whole idea all together as we discover new things about cars all the time. I figured that it is possible, but it didn't make sense and I was wondering if someone could support the theory with data from experiments or at least in well supported theory.The only thing I've ever heard this about that made any sense were small displacement, ultra high-revving F1 engines that have exotic valvetrain components for their lightweight characteristics (i.e. creating a cushion to keep the valves from thrashing back and forth); that being said, I can't see an application on a modern production engine and agree with slapping the 'ol paper towel tube on the Vibe if possible... Pete

I have the Flowmaster 60 delta flow and it is the perfect match with the Vibe GT.

Quote, originally posted by blk182@n7 »I have the Flowmaster 60 delta flow and it is the perfect match with the Vibe GT. How is the noise volume? Is there any resonance at cruising speeds?

I wish I could get an exhaust and CAI