Exhaust Back Pressure test ?
#1
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Does anyone konw of cheap methods to measure exhaust gas pressure? I want to know how much back pressure my stock cat back exhaust is creating. I'm curious how much the stock resonators and stock sc300 mufflers hurt flow.
My current exhaust is 3 inch crush-bent downpipe, 3 inch mandrel bent midpipe connected to stock SC300 catback exhaust:
![](http://i19.photobucket.com/albums/b188/dejacky/Downpipe3.jpg)
![](http://i19.photobucket.com/albums/b188/dejacky/Exhaust2.jpg)
My current exhaust is 3 inch crush-bent downpipe, 3 inch mandrel bent midpipe connected to stock SC300 catback exhaust:
![](http://i19.photobucket.com/albums/b188/dejacky/Downpipe3.jpg)
![](http://i19.photobucket.com/albums/b188/dejacky/Exhaust2.jpg)
![](http://i19.photobucket.com/albums/b188/dejacky/Exhaustcheapsolution.jpg)
#3
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cheapest way is to borrow a couple friend's exhausts (different sizes and manufacturers) and see if they make more top end power. thats about as cheap as you can go...or you could just do some math for flow and see if the exhaust you are running is too large/small. most people go off the generic sizing which is usually 3" for about 300-400whp, 3.5" for 400-550, and 4" for 550+
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Originally Posted by jbrady
1/8" NPT threaded hose barb, high temp 1/8" ID vacuum hose, boost gauge.
Drill and tap test site, connect hose and gauge, run test.
Drill and tap test site, connect hose and gauge, run test.
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#8
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Originally Posted by dejacky
Thank you!
Can I just use the threaded bung on my downpipe instead? It has a wideband 02 sensor in it that isn't required for the car to work, etc.
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Originally Posted by dejacky
Where can I find fittings that will convert everything down to that vacuum hose size for a boost guage?
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