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2.5" versus 3" exhaust
Posted: Mon Jul 22, 2019 9:58 am
by amulheirn
I think the original cobras had 2.5" exhaust systems, is that right? I think the Hawk one is a 3" one (not actually measured it though - maybe I need to recalibrate my eye).
Anyway, I thought this piece of testing by Hotrod magazine was quite interesting:
https://www.hotrod.com/articles/engine- ... h-exhaust/
Re: 2.5" versus 3" exhaust
Posted: Mon Jul 22, 2019 6:34 pm
by peterc
Well who’s a lucky boy if you have a 3” or even a 2.5”
Just measured mine at 2.25” at the down pipe and 2.125” for the remainder. Suggests 2” bore with 1/16” wall.
Peter C
Re: 2.5" versus 3" exhaust
Posted: Mon Jul 22, 2019 7:10 pm
by simonjrwinter
It’s not how big it is...it’s how you use it....

Re: 2.5" versus 3" exhaust
Posted: Mon Aug 19, 2019 9:34 pm
by monster7
Gents,
i'm in the situation to re-do my exhaust system and i'm wondering if anyone is using and can thereof provide some pictures and infos of Gerrys standard setup for the 289 FIA sidepipes (siderails). I have some inserts from Classicchambered Exhaust which will fit into a 3'' pipe (no muffler visible from outside), and i think Gerry setup could be at least a good starting point.
Thank you for the help!
Ronald
Re: 2.5" versus 3" exhaust
Posted: Tue Aug 20, 2019 2:16 am
by nikbj68
Here is one of my sidepipes, the downpipes from the headers are 2 1/4”.
(Rover 3.5)
Re: 2.5" versus 3" exhaust
Posted: Tue Aug 20, 2019 10:34 am
by Migge
What is the additional bemd for?
Re: 2.5" versus 3" exhaust
Posted: Tue Aug 20, 2019 3:07 pm
by Karl
The additional bend is to connect a silencer (when needed)
Karl
Re: 2.5" versus 3" exhaust
Posted: Tue Aug 20, 2019 3:39 pm
by Frank289
Untouchable, i think im one of the lucky ones who has no sound restriction on my car papers, there is somewhere a code where police can see that. So i can put anything unther my obra and no ticket, just have to make some demoers for the TUV
Re: 2.5" versus 3" exhaust
Posted: Tue Aug 20, 2019 3:45 pm
by monster7
Thanks for the picture Nic

Re: 2.5" versus 3" exhaust
Posted: Tue Aug 20, 2019 5:17 pm
by Migge
Additional 2nd silencer? too heavy
