3" pipes or 2 1/2' with cutouts?

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kanders

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I'm going to order a Jegs or Summit exhaust kit and would like opinions. Should I go with 2 1/2" and use manual plate cutouts on race day or install 3" and leave connected for racing. 3" would be less to do come race day, 2 1/2 would mean removing the plates but sound better when racing.
 
I'm going to order a Jegs or Summit exhaust kit and would like opinions. Should I go with 2 1/2" and use manual plate cutouts on race day or install 3" and leave connected for racing. 3" would be less to do come race day, 2 1/2 would mean removing the plates but sound better when racing.

You should get the pipe diameter that best fits your combo.
 
I have a custom 3" setup on my duster which exits with 2 1/2 tailpipes and factory tips,i also have dump pipes right after the collectors,testing i've found the car runs no faster with the caps open just a lot LOUDER....
 
Unless you are in access of 500 HP a closed 2.5" system will be fine for the street or race day.

If you feel the need for cutouts there are electrically operated ones so they can be opened and closed with a flick of a switch.
 
I was running open TTI headers with extensions for several years. A few years ago I installed a 3" TTI X-pipe connected to 3" Dynomax Ultraflo's ending at the rear end housing. After a little carb tuning and removing the 60 lbs that the system added from elsewhere in the car to get the car back to its previous weight, it was at least several hundredths faster than before!
It worked for my combo. As the fine print usually says: "Your results may vary."

I've gotten several compliments from the open header guys and I can just hear my Holley blue pump at idle. Why bother with cut-outs?
 
I have a custom 3" setup on my duster which exits with 2 1/2 tailpipes and factory tips,i also have dump pipes right after the collectors,testing i've found the car runs no faster with the caps open just a lot LOUDER....

The reason I was thinking 2 1/2" is also so I can use factory tips. Would there be an advantage to a 3" system when its restricted to 2 1/2" at the end? Kev
 
Thanks for the input guys, it seems both systems work for different people in different setups. Hmmmm......eeenee meenee minee mo.
 
The reason I was thinking 2 1/2" is also so I can use factory tips. Would there be an advantage to a 3" system when its restricted to 2 1/2" at the end? Kev

I have factory style stainless tips on 2 1/2" tailpipes freeflowing exhaust restrictions are not a concern..3" for big blocks,not when your small block is putting out what most big blocks do or better...to each his own..
 
The reason I was thinking 2 1/2" is also so I can use factory tips. Would there be an advantage to a 3" system when its restricted to 2 1/2" at the end? Kev

The 2 1/2" tips would be a choke point.
But don't some companies make OEM style tips for bigger pipes?
 
The 2 1/2" tips would be a choke point.
But don't some companies make OEM style tips for bigger pipes?

Way back in the day, I took a set of factory 340 tips and cut them at the point were they measured 2 1/2" (hope that makes sense), then had them welded to my 2 1/2" system.
 
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