I'm organising some pacemakers, high flow cat and high flow muffler. The dude who is installing it recommends me to replace the 2.5" with a 3". Anyone's advice would be appreciated. Cheers.

Correct me if I am wrong but doesn't the magna's verada's have a 2.5" mandel bent exhaust already??? and also isn't a 3" normal the same as a 2.5" mandel bent??

i think the magna's come with a 2 1/4" mandrel bend, but supposed ly the best set up (unless goin turbo) is a 2 1/2" mandrel, which really won't do alot unless you are going for significantly higher power figures

This has been discussed recently I think...and if I remember rightly, it was Redav that measured the exhaust, it varies between 2 1/4" and 2 1/2" but it was mandrel bent. I would stick with what you have for now. You can always go bigger later.

But the pacemakers all join up into a 2 1/2" pipe anyway, so I wouldn't worry too much.

Keep it as is for now.

This has been discussed recently I think...and if I remember rightly, it was Redav that measured the exhaust, it varies between 2 1/4" and 2 1/2" but it was mandrel bent. I would stick with what you have for now. You can always go bigger later.

That's what it looked like. I'd say that the 3.0's had something around the 2.25 mark and 3.5's are almost 2.5. Sounds like he wants your money or doesn't know what he's on about if he's saying 3' is the way to go. I'd go 3' only if you've gone the forced induction path or some extremely serious NA mods. Even Booya still has 2.5' as far as I can remember... Ben???

Just swap the muffler and the saved money can go on the headers.

the 3.0 and 3.5 are the same exhaust system. they are 2.5 mandrel most of the way, and only the last section before the rear muffler is 2.25, the cat is already 2.5,
I would only replace the last section of 2.25 along with the rear muffler, the money spent on the rest of the piping and 3.0 cat could go towards good extractors. as someone already mentioned, 3.0 inch only necessary if u r seriously working the engine.

yeah, i wouldn't go to 3"... would not help it much at all.... i was told (by lukey emails dude) that the system at the moment is 60mm system which is in between 2¼" and 2½"... they actually use metric these days!!! who'ld have thought :P

(note: if 3" press bent.... that will give about same performance as 2½" mandrel bent system!)

I'd save the money on the high-flow cat and get your headers ceramic coated instead! The standard cat isn't really all that restrictive.. think about it, if you can get more power by replacing your muffler with a high flow unit and the muffler is after the cat, how restrictive can the cat be? Surely it must be less restrictive than the muffler to begin with, yeah?

the cat is meant to contribute about just as much restriction as the rear muffler - normally - have noticed it stays hot long after the rest has cooled. but apparently the stock magna exhaust has a very restrictive muffler and a very good flowing cat- thats what i was told by exhaust shop.

i was told (by lukey emails dude) that the system at the moment is 60mm system which is in between 2¼" and 2½"...

That's exactly what Mitsu said to me. It's close enought to 2.5 to call it 2.5. And I'm pretty sure that the piping varies between the two. Mine's definately not 2.5.

you might even have power losses going to 3" due to lack of back-pressure.

you might even have power losses going to 3" due to lack of back-pressure.

You'd probably gain top end with the right mods but you'll be loosing bottom end. No point having a screaming top end if it takes ages to get there.

and it would probably drone or sound crap as well if it wasnt for a fully worked motor.