Author Topic: Anti-Pod mod?  (Read 15966 times)

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Offline Syscrush

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Re: Anti-Pod mod?
« Reply #75 on: November 29, 2011, 07:53:08 AM »
Wouldn't that make it unbalanced? Also decrease the overall torque and horsepower? Sounds cool in theory though
Yes, they're a bit unbalanced, but there are imbalances already due to the differences in temperature (inboard cyls will generally be hotter).

It would decrease peak torque (and therefore hp), but it would broaden/flatten the torque curve, which is desirable for some applications.
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Offline orkid1989

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Re: Anti-Pod mod?
« Reply #76 on: November 29, 2011, 08:05:28 AM »
Wouldn't that make it unbalanced? Also decrease the overall torque and horsepower? Sounds cool in theory though
Yes, they're a bit unbalanced, but there are imbalances already due to the differences in temperature (inboard cyls will generally be hotter).

It would decrease peak torque (and therefore hp), but it would broaden/flatten the torque curve, which is desirable for some applications.
sounds cool.
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Offline Syscrush

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Re: Anti-Pod mod?
« Reply #77 on: November 29, 2011, 08:15:03 AM »
Factory Pro sells this 35/70 mixed stack kit for use with the stock airbox on an SV650:

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FWIW, I'm not a shill for Race Tech - I've just got a thing for good suspension and the RTCE's are the most cost-effective mod for these old damping rod front ends.

Offline Tintop

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Re: Anti-Pod mod?
« Reply #78 on: November 29, 2011, 07:46:16 PM »
A lot of the CanAm cars ran slightly different length stacks (~15mm?) on the 427 Chevy engines.  The SV650 setup looks interesting Syscrush, however I wonder about its effectiveness.  From the picture it looks like one stack is shorter because of a height restriction caused by the stock air box.  Also there would appear to be about 30mm+ difference in length.  To me this would lead to a 'push me / pull me' situation between the 2 cylinders over the rpm range.

I would point out though, that the stock stacks used on the 550/4 are slightly different in length.  Both 1 & 4 are longer than 2 & 3, but only by about 5mm.  This would appear to have been done so that 1 & 4 could bend slightly inwards.  Thus keeping the stock plenum a bit narrower, and also providing clearence around the frame rails on each side.
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Offline Syscrush

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Re: Anti-Pod mod?
« Reply #79 on: November 30, 2011, 03:12:30 PM »
A lot of the CanAm cars ran slightly different length stacks (~15mm?) on the 427 Chevy engines.  The SV650 setup looks interesting Syscrush, however I wonder about its effectiveness.  From the picture it looks like one stack is shorter because of a height restriction caused by the stock air box.  Also there would appear to be about 30mm+ difference in length.  To me this would lead to a 'push me / pull me' situation between the 2 cylinders over the rpm range.
They're 35mm different, and seem to do just what one would expect.  Here's a dyno for the mixed setup:

EDIT: Thanks to fang for pointing out that I had posted the same chart twice.  Here's the correct one...
And for the high-rev setup with 2 short stacks:

Anyhow, I'm not advocating for stacks this different, but looking at those 2 dynos it does seem to support the theory.
« Last Edit: December 01, 2011, 04:25:58 AM by Syscrush »
Life is precious: wear your f'n helmet!
There's nothing more expensive than a free bike...
FWIW, I'm not a shill for Race Tech - I've just got a thing for good suspension and the RTCE's are the most cost-effective mod for these old damping rod front ends.

Offline brandEn

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Re: Anti-Pod mod?
« Reply #80 on: November 30, 2011, 09:20:25 PM »
Here are my stacks for the CR29 carbs
 

 

 

 

Offline Terry in Australia

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Re: Anti-Pod mod?
« Reply #81 on: December 02, 2011, 07:15:37 PM »
Subscribed, thanks Mick! ;D
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Offline Retro Rocket

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Re: Anti-Pod mod?
« Reply #82 on: December 02, 2011, 07:28:54 PM »
No problemo..... ;)
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Offline orkid1989

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Re: Anti-Pod mod?
« Reply #83 on: December 02, 2011, 07:40:28 PM »
Thanks for the pictures and o apologize for so few updates. At the moment I am still waiting to hear back from my machinist
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Offline Old Scrambler

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Re: Anti-Pod mod?
« Reply #84 on: August 17, 2015, 03:01:04 PM »
Trying to revive an old thread.....................Regarding the stacks for RS34s............I found suitable stacks could be adapted from a Suzuki GSX750F Katanna  2000-2005 into the stock F2 airbox and believe they would fit the anti-pod filter.......... but you may need to trim the outer stacks for length.  I had to enlarge the holes in the airbox and mostly removed the inner filter plate to get air to the outer carbs...............

So did the mounting plate and filters become a reality?  I could be interested to try a set on my C.B.R. at Bonneville...........in 2016 ;)
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