View Poll Results: Would you like custom long carbon fiber velocity stacks for around $250 + shipping?
Yes
6
16.67%
No
30
83.33%
Voters: 36. You may not vote on this poll
Long Carbon Fiber Velocity Stacks
Thread Starter
Fastest Color
SuperBike
Joined: Jul 2007
Posts: 2,091
From: Lithia, FL
Long Carbon Fiber Velocity Stacks
Just gauging interest in a possible group order for long carbon fiber velocity stacks. They would be modeled after my billet stacks and would run around $250 USD + shipping. This is the shop that would custom build them for us:
http://www.carbonpartz.net/
I installed these pictured below and got a nice gain according to my butt dyno
They are rated at +2hp, but I figure they can be combined with a high flow filter such as K&N with rejetting for more...
http://www.carbonpartz.net/
I installed these pictured below and got a nice gain according to my butt dyno
They are rated at +2hp, but I figure they can be combined with a high flow filter such as K&N with rejetting for more...
Last edited by FL02SupaHawk996; Apr 22, 2009 at 07:12 AM. Reason: added benefits
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From: Montreal
If I may then. I seem to recall that these runners, developed on a flow bench and both longer than the longest OEM unit, are designed to work at low and middle rpms (as opposed to just 8K and up as would a pair of short ones). They are said to beef up the mid-range considerably to the tune of about 5 hp when dialed in (and isn`t the mid-range torque what we love so much about these engines?) without hurting top-end (compared to stock stacks) due to their ability to flow more air.
there you go....
On a personal note, I want to incorporate these into my future rebuild (along with slightly oversize custom JE pistons, in addition to my existing ported heads, Yosh cams,....)
there you go....
On a personal note, I want to incorporate these into my future rebuild (along with slightly oversize custom JE pistons, in addition to my existing ported heads, Yosh cams,....)
Last edited by mikstr; Apr 22, 2009 at 07:34 AM.
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From: Montreal
Yep, I have been doing just that for years now (actually believe I am the one who introduced the idea to this forum years ago after having read about it elsewhere). These are said to be significantly better than that, however. Granted, this is not for everyone, but for those looking for that little extra, it is the next logical step.
Slacker
Superstock
Superstock
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From: San Antonio, TX
If someone could make these out of a more appropriate material for this application, such as ABS plastic, and the price was around $50 then there would likely be considerable interest. I cannot justify pricey carbon fiber for use inside the air-box. Not on a street machine especially.
ole dirty bastard
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Posts: 1,548
From: MN
ok, simple question here and I'm sure its been hashed over many times, but I'm lazy today plus this topic warrants the discussion. Why did the factory design 2 different length stacks? what other changes are you making to compensate for adding the longer front stack? I do know the HRC carb kits came with slide's that were modified - but for a nonmodified airbox they only suggested replacing the front slide (guessing to slow it down, it had an bleed hole I believe).
my point is I'm guessing jetting that front carb could be trickier after changing the stack length, and any benefit might be only in the context of other changes in cams, exhaust or otherwise. Does anyone have data on the benefits of simply replacing the shorter stack and seeing HP and not messing up low speed jetting?
my point is I'm guessing jetting that front carb could be trickier after changing the stack length, and any benefit might be only in the context of other changes in cams, exhaust or otherwise. Does anyone have data on the benefits of simply replacing the shorter stack and seeing HP and not messing up low speed jetting?
Thread Starter
Fastest Color
SuperBike
Joined: Jul 2007
Posts: 2,091
From: Lithia, FL
ok, simple question here and I'm sure its been hashed over many times, but I'm lazy today plus this topic warrants the discussion. Why did the factory design 2 different length stacks? what other changes are you making to compensate for adding the longer front stack? I do know the HRC carb kits came with slide's that were modified - but for a nonmodified airbox they only suggested replacing the front slide (guessing to slow it down, it had an bleed hole I believe).
my point is I'm guessing jetting that front carb could be trickier after changing the stack length, and any benefit might be only in the context of other changes in cams, exhaust or otherwise. Does anyone have data on the benefits of simply replacing the shorter stack and seeing HP and not messing up low speed jetting?
my point is I'm guessing jetting that front carb could be trickier after changing the stack length, and any benefit might be only in the context of other changes in cams, exhaust or otherwise. Does anyone have data on the benefits of simply replacing the shorter stack and seeing HP and not messing up low speed jetting?
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MotoGP
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Posts: 5,631
From: Montreal
Hi again Rick,
just curious as to why the price is so steep. I found a thread on Speedzilla where he is making a pitch for his RC51 carbon stacks at "$120-ish" (http://www.speedzilla.com/forums/rc5...mpet-pics.html). In yet another he mentions $200 for said stacks. Just curious as to why the premium for the VTR units (maybe we could get more peope to buy in if they were a bit cheaper)...
cheers
just curious as to why the price is so steep. I found a thread on Speedzilla where he is making a pitch for his RC51 carbon stacks at "$120-ish" (http://www.speedzilla.com/forums/rc5...mpet-pics.html). In yet another he mentions $200 for said stacks. Just curious as to why the premium for the VTR units (maybe we could get more peope to buy in if they were a bit cheaper)...
cheers
Thread Starter
Fastest Color
SuperBike
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Posts: 2,091
From: Lithia, FL
Mikstr, that's the price he gave me
Guess we could look elsewhere...you think Truck could turn them outta aluminum?
Guess we could look elsewhere...you think Truck could turn them outta aluminum?
Last edited by FL02SupaHawk996; Apr 24, 2009 at 05:32 AM. Reason: spell
Thread Starter
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From: Lithia, FL
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From: Montreal
If I may, I would think the critical measurements are the overall length, taper, and bell-mouth radius (all the things are affect airflow). AS these were designed on a flow-bench, I think it`s critical to get them virtually identical.
Thread Starter
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SuperBike
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From: Lithia, FL
LOL
Thread Starter
Fastest Color
SuperBike
Joined: Jul 2007
Posts: 2,091
From: Lithia, FL
Senior Member
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Joined: Apr 2005
Posts: 5,631
From: Montreal
If I may comment, as this scheme was basically my idea, the CF is not the important part of this project. I merely suggested it as the chap who was initially contacted made some simlar ones for the RC51, proving it could be done for the VTR. To be honest, I personally do not care much what material they are made from (so long as they are durable). The key ingredient is to have stacks that match the dimensions of Rick`s and bolt up properly. Anyone with other suggestions please speak up. The cheaper we can get them, the better it is for all of us.
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From: Montreal
these stacks are designed for stock or non-race engines (the same chap builds short stacks for highly modified high-rpm applications). Here is info I received in an e-mail from the guy who developed them:
"The long series are designed to improve the torque of the engine lower mid and mid to mid upper RPM range, but will not lift the Max top end HP. They simply bolt on in place of the original stacks. Both front and rear stacks are the same length in the long series and are about 20% longer than the longest original velocity stack. You will most likely have to drop the jet sizes slightly with these stacks."
"The long series are designed to improve the torque of the engine lower mid and mid to mid upper RPM range, but will not lift the Max top end HP. They simply bolt on in place of the original stacks. Both front and rear stacks are the same length in the long series and are about 20% longer than the longest original velocity stack. You will most likely have to drop the jet sizes slightly with these stacks."
