2.5 cutout on a 3 inch catback
Thread Starter
On The Tree
Joined: May 2018
Posts: 145
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2.5 cutout on a 3 inch catback Like the title says, wondering if I can slap a 2.5 inch electric cutout on a 3 inch magnaflow catback?
Any losses/downsides compared to a 3inch cutout?
I have a 2.5 inch cutout lying around.
Thanks in advance.
Any losses/downsides compared to a 3inch cutout?
I have a 2.5 inch cutout lying around.
Thanks in advance.
Thread Starter
On The Tree
Joined: May 2018
Posts: 145
Likes: 2
The muffler shop I spoke with said the cutout might make 1-2 less hp than a 3 inch but it cant hurt performance. Not sure how true this is.
Its either 2.5 inch cutout or no cutout. I probably wouldnt bother buying one.
Its either 2.5 inch cutout or no cutout. I probably wouldnt bother buying one.
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It will be fine. You have to remember exhaust doesn't only go out of the cutout, it still goes through the pipe also.
If had exhaust ONLY going through a 2.5 or a 3 then it would matter. But once you open that cutout you'll have exhaust coming out of it and the exhaust system, and just like dual 2.5" flows more than a single 3", you'll have more flow with the 2.5" open cutout open than you would with just the exhaust. So yes the cutout will work and yes it'll be fine.
What size is your current exhaust and how much power are you making? If you have decent exhaust you probably won't gain anything from the cutout anyway, except noise.
If had exhaust ONLY going through a 2.5 or a 3 then it would matter. But once you open that cutout you'll have exhaust coming out of it and the exhaust system, and just like dual 2.5" flows more than a single 3", you'll have more flow with the 2.5" open cutout open than you would with just the exhaust. So yes the cutout will work and yes it'll be fine.
What size is your current exhaust and how much power are you making? If you have decent exhaust you probably won't gain anything from the cutout anyway, except noise.
Thread Starter
On The Tree
Joined: May 2018
Posts: 145
Likes: 2
The exhaust I am planning to put it on is a magnaflow 3 inch catback. American racing headers with a catted y pipe. Car has a small tr224 114 cam. 370whp.
Future goals are a fast intake and 243 heads shooting for 400whp.
Yeah Ive seen people gain anywhere from 1-10whp with cutouts. Not sure where I would fall on that scale.
Future goals are a fast intake and 243 heads shooting for 400whp.
Yeah Ive seen people gain anywhere from 1-10whp with cutouts. Not sure where I would fall on that scale.
The exhaust I am planning to put it on is a magnaflow 3 inch catback. American racing headers with a catted y pipe. Car has a small tr224 114 cam. 370whp.
Future goals are a fast intake and 243 heads shooting for 400whp.
Yeah Ive seen people gain anywhere from 1-10whp with cutouts. Not sure where I would fall on that scale.
Future goals are a fast intake and 243 heads shooting for 400whp.
Yeah Ive seen people gain anywhere from 1-10whp with cutouts. Not sure where I would fall on that scale.
With your current exhaust you'd be on the high side of the cutout gains, with the magnaflow you'd be at the bottom "what's the point of having one" range.
So in other words if you have to reduce the 3" to 2.5" to cut in the cut out, then you'll lose because the exhaust will hit the 2.5" before it hits the cutout essentially leaving you with a 2.5" bottle neck in the system. I can't believe I didn't read that right to begin with..
Thread Starter
On The Tree
Joined: May 2018
Posts: 145
Likes: 2
No reducing the 3 inch pipe. They want to cut a hole in the catback 3 inch pipe and weld a 2.5 pipe into it so it just beaches off the catback.
Im sure if I really pushed for it they would swap it for a 3inch. I paid for cutout and the correct product application according to QTP is a 3 cutout. They did the 2.5 without asking. Im sure they had good intentions with ground clearance though.
Im sure if I really pushed for it they would swap it for a 3inch. I paid for cutout and the correct product application according to QTP is a 3 cutout. They did the 2.5 without asking. Im sure they had good intentions with ground clearance though.
No reducing the 3 inch pipe. They want to cut a hole in the catback 3 inch pipe and weld a 2.5 pipe into it so it just beaches off the catback.
Im sure if I really pushed for it they would swap it for a 3inch. I paid for cutout and the correct product application according to QTP is a 3 cutout. They did the 2.5 without asking. Im sure they had good intentions with ground clearance though.
Im sure if I really pushed for it they would swap it for a 3inch. I paid for cutout and the correct product application according to QTP is a 3 cutout. They did the 2.5 without asking. Im sure they had good intentions with ground clearance though.
I would try to keep everything as big as possible, that's the goal. If it were mine I would probably be trying to figure out a way to make that 2.75 a 3
