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Exhaust Advice
Nick DV - 24/1/14 at 08:48 AM

I need to alter the position of the exhaust can, but I do not want to spend shed loads of money at the moment - and I can't find anyone local that can build collectors!

The current setup is 4-2-1, but as I have a spare 4-1 collector and a local exhaust place have said they can easily bend and weld a single pipe between the collector and the can, that appears to be my best bet.

Therefore, if I decide to go down that route, would I notice any difference in performance going from 4-2-1 to 4-1? I've looked at lots of BECs and there seems to be plenty of them using both set ups! Confusing!!

Any advice would be gratefully received

Nick


40inches - 24/1/14 at 09:00 AM

I used the standard bike header, ZX9R, this is 4-1 also. No problem with ground clearance
ZX9R-E manifold
ZX9R-E manifold


Nick DV - 24/1/14 at 09:06 AM

quote:
Originally posted by 40inches
I used the standard bike header, ZX9R, this is 4-1 also. No problem with ground clearance
ZX9R-E manifold
ZX9R-E manifold



That's a nice, simple set up


T66 - 24/1/14 at 09:24 AM

Osprey exhausts made my collector. Top service - they also sell all the components you may need at reasonable cost.


http://www.ospreyexhaustcomponents.co.uk


Nick DV - 24/1/14 at 09:30 AM

quote:
Originally posted by T66
Osprey exhausts made my collector. Top service - they also sell all the components you may need at reasonable cost.


http://www.ospreyexhaustcomponents.co.uk


That may be a solution, but I wouldn't know if the 4-1 or 2-1 collectors would match my primary pipes. If they did and I could weld .........


T66 - 24/1/14 at 10:38 AM

They will modify anything to your spec, give them a call.



[Edited on 24/1/14 by T66]


loggyboy - 24/1/14 at 10:44 AM

quote:
Originally posted by 40inches
I used the standard bike header, ZX9R, this is 4-1 also. No problem with ground clearance
ZX9R-E manifold
ZX9R-E manifold



Just out of interest, are those horizontal pipes linking the headers, or are they just bracing/support?


Nick DV - 24/1/14 at 10:57 AM

quote:
Originally posted by T66
They will modify anything to your spec, give them a call.


Thanks for that, and if I get stuck, I may well do


mark chandler - 24/1/14 at 11:07 AM

Do not expect any real performance gains, sorry.

The optimum header length needs to be around 24" + another 12" to the can from memory, whatever you do there will not be sufficient space to achieve this while leaving the can on the side.

4:1 is tuned to max torque at certain rev range, 4:2:1 gives a wider spread of torque but a little less at peak, unless your exhaust is horribly restrictive I doubt if you note any difference, it may even become slower the sweet spot closes up.

To toggle the peak point you shorten primaries to raise the rpm, so advantage then will be high in the rev range which is not where you normally drive the car.


Nick DV - 24/1/14 at 01:49 PM

quote:
Originally posted by mark chandler
Do not expect any real performance gains, sorry.

The optimum header length needs to be around 24" + another 12" to the can from memory, whatever you do there will not be sufficient space to achieve this while leaving the can on the side.

4:1 is tuned to max torque at certain rev range, 4:2:1 gives a wider spread of torque but a little less at peak, unless your exhaust is horribly restrictive I doubt if you note any difference, it may even become slower the sweet spot closes up.

To toggle the peak point you shorten primaries to raise the rpm, so advantage then will be high in the rev range which is not where you normally drive the car.


Thanks Mark. TBH I had a suspicion that this would be the case, and I suppose this is why I see as many BEC with a 4-2-1 set up as there are 4-1 Anyway, with the way I drive, I'll never notice the difference

[Edited on 24/1/14 by Nick DV]


40inches - 24/1/14 at 02:07 PM

quote:
Originally posted by loggyboy
quote:
Originally posted by 40inches
I used the standard bike header, ZX9R, this is 4-1 also. No problem with ground clearance
ZX9R-E manifold
ZX9R-E manifold



Just out of interest, are those horizontal pipes linking the headers, or are they just bracing/support?


This is the E series header, the link pipes improve mid range torque. It is a well tried mod on C series engines, apparently
the difference is noticeable, although I haven't used the C series header so can't say from personal experience.