Cutout flow question
#1
Cutout flow question
I'm just curious with a cutout, when you have the butterfly valve closed does exhaust get trapped in the angled piece of pipe??? Even when a Cutout is opened all of your exhaust doesnt flow out the actual Cutout, right? Some exhaust must still flow through the muffler and out the tail pipes.
I'm just wondering how they are so effective when it seems a Cutout could trap exhaust. Anyone have any technical info on Cutouts?
I'm just wondering how they are so effective when it seems a Cutout could trap exhaust. Anyone have any technical info on Cutouts?
#2
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I'm sure the closed cutout does trap some of the exhaust and probably causes some turbulence. I don't think it costs you enough power to measure. With mine open, I still get a good amount of flow going through the muffler. Before you put the cutout on the car you could grind the opening going to the angled piece and make it as large as possible. Mine had alot of room for improvement, I just didn't have time to open it up more.
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I think that at idle, some will obvioulsy get trapped if closed, and a decent amount will go through muffler. At WOT, Id think itd want to find the quickest way to get out, and more would go through the cutout if open, or would flow by the closed cutout and go out the exhuast.
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Although good mufflers optimize gas flow, the baffling and turning turbulence has to be considerable; certainly more than the single interruption of a Y-adapter cutout. When back pressure gets low enough, turbulence shouldn't be an issue unless the goal is to create negative pressure.
Just for interest sake, if you go to the QTP website you can find the dyno readings for a Dick Harrell edition 2002 Camaro, with and without the cutout open.
http://www.quicktimeperformance.com/QTEC/
Just for interest sake, if you go to the QTP website you can find the dyno readings for a Dick Harrell edition 2002 Camaro, with and without the cutout open.
http://www.quicktimeperformance.com/QTEC/
#5
Damn, thats a lot of power increase on that Dyno chart. Amazing what a little cutout can do. Good info, thanks a lot guys!
Should I go with a McCord or QTP? I've heard a lot of people complaining about QTP's, very little about McCords. I just want this thing to work and last!
Should I go with a McCord or QTP? I've heard a lot of people complaining about QTP's, very little about McCords. I just want this thing to work and last!
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A cutout is a good hp to dollar mod. The electric ones are mucho fun to play with as well.
You can see by my sig what I have on the LT1. This forum promotes its promoters and obviously QTP is good using stainless.
There is another brand that offers a 4 year warranty if you are going to be using it often. As for me, I probably won't open mine much after the novelty has worn off.
You can see by my sig what I have on the LT1. This forum promotes its promoters and obviously QTP is good using stainless.
There is another brand that offers a 4 year warranty if you are going to be using it often. As for me, I probably won't open mine much after the novelty has worn off.