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if you are happy we are happy.not trying to stir the pot just thinking out loud.
You know?
I just like to put my .02..
Manufaturers put X" diameter pipe to match up the engine, they dont go "Mike, what size pipe you want to install on the GTP, 2 1/4 sounds good?
Its all done for a reason, they are based on formulas.
I love disscussions! the why do they put the restrictive manifolds and the U-bend in with a supercharged car? I know the U-bend was placed there for the o2 sensor, but it could have been easily configurated to be placed on the side and not the bottom. Also, if we all thought as "Mike" does, then we would have 240hp (at the crank) and 280lbs of factory torque. The factory had to meet emission and certain insurance classifications. Just like the 87 Buick GN and the 87 Buick GNX. They were way over the factory HP and torque rating(not saying our L67's were or were not). Im gald I do not think like "Mike". I dont wanna be like Mike. LOL. Thanks for the input though. Oh yeah, stand buy for exhaust pics.
If all this is correct, then give me an explanation for the U-Bend in a higher performance, boosted platform.Quote:
Originally Posted by Javi
I agree. I think the factorys have certain standards that they must meet. If they were making 300hp family sedans (buick anyway) back in the 90's early 00's, the that may have increased insurance, more emissions, which= not so hot sales. Im guessing here, purley guessing, but its probably not to far off the beating path.
It will not allow me to upload my pic for some reason. I feel dumb. It just says 'upload failed'. I have it under a JPG file? No Idea.
all i know is a muffler that faces backwards and a pipe that goes in through side of that muffler using a 90* bend is not what i call free flowing. that is restrictive and that is what came on my 98 GS. i dont have headers on it but i drove my buddys old gtp with headers and slp loudmouth 2.5in, my 3in single still felt more driveable on low rpm's. sounded good but our 1/4 speeds were about the same.
Regal 98, you ask me where i live. I live near Eastgate.
here is why you dont need a 3" catback:
by the time the exhaust gases get to the catback, they have cooled down considerably since the downpipe area. this means they are now taking up less space because they have cooled down (thermodynamics 101). if you use too big of piping the exhaust gases now slow down and lose velocity. you do not care about scavenging, you care about velocity. with smaller piping you dont lose that velocity and your exhaust is therefore more efficient.
make sense? this is why i tell people 2.5" is more than enough for anything after the cat.
get pics and video please i would like to listen to this
makes sense in some way. but is this coming from guys with big V8's and n/a 4's or should it apply to s/c and turbo cars? cause i know on track cars and turbo cars the mufflers can get to extreme temps. i like mines sound with single 3in mufflereither way thoughQuote:
Originally Posted by Bio248
it applies on all vehicles. exhaust acts the same way, regardless of the power adder. however, turbo cars benefit from bigger exhaust because of the amount of boost they produce, therefore producing a larger amount of exhaust gases. because of the more volume of exhaust, the car is able to keep velocity of the exhaust with bigger piping. in our cars, we do not produce enough boost to make a difference so 2.5" is more than enough for anyone wanting an aftermarket exhaust.
so a 3" exhaust on a blown 3800 does nothing but increase volume and potentially LOSE power.
Quote:
Originally Posted by Bio248
:th_thumbsup-wink:Quote:
Originally Posted by Bio248
in other words:
Think of a large diameter straw versus a small diameter straw. When you drink from a large diameter straw, you get more of what you're drinking but it doesn't go very far inside of your mouth. A smaller diameter straw moves the liquid quicker and farther into your mouth.
What happens to exhaust gases as they cool down? As exhaust gases cool, they slow down. Think about what happens when the you are running and exhale slower. Takes you longer to catch your breath. Right?
Where in the exhaust system do the gases cool down and is it farther down the system as you increase rpm? Gases begin to cool almost immediately. Not by a significant amount and yes, it is always further down the exhaust system that they cool the most. A larger exhaust system (more surface area) will cool the gases more quickly.
Where is the pulse based exhaust scavenging concentrated at? The scavenging depends on the entire exhaust system (pipe diameter and length, header design, muffler design, back pressure, etc.).
there are several 500 +wheel HP cars with 2.5" exhaust sytems driving around
Z06,camaros,rustangs,T/As,Evos etc etc....
Get a photobucket account... its free... you don't have the restrictions the forum uploaders do.Quote:
Originally Posted by SleeperGS
Then just link it :th_thumbsup-wink:
You guys keep referring to is as 'Cat back'. I have no cat, just a DP. Car is for off road use only. Anyways, there is no restrictions. Headers to DP, DP to Glasspack, glasspack to twin Thrush welds. Yes, I need a photobucket account.
2 pages of bs and still no pictures or videos, come on. :)
that's the point. we are telling you that the 'no restrictions' is a bad thing.Quote:
Originally Posted by SleeperGS
I have 3" on my GTP, but it ain't no mandrel bent set up. By the time the 3" is just bent, and crimped for the angles, the I.D. is around 2.5" roughly. The first time we did it, we used 2.5" pipe, and after my accident, they cut my old pipes off and apart, and saw that the I.D. at the bends was stock size. So, thats why we went 3" the second time.
I too can't wait to see some pictures! So, quit being such a dick tease, and post em up. LOL :th_thumbsup-wink:
~F~
O2 sensors are supposed to be installed on the top of the pipe.
they last longer that way.
^yup,
they think with them installed that way, they can drip or get rid of any excess moisture that builds up on them, vs. them on their side.
Also, they were afraid of the expensive sensor being hit by debris from under the car, so they mounted it on top to protect it.
~F~
Where are pictars