V+ plus...spacer?
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From: Irvine
V+ plus...spacer?
Hey guys, sup? 'bout to buy a V+ and was thinking about maybe even getting a spacer from say motordyne. I know some of you love the v+, some of you hate it...all's well, to each his own...but, let's ignore personal views on the v+ that you may have and my question is: do you think motordyne's spacer (i dunno...5/16ths?) would fit with the kinetix? i'm assuming it would given aftermarket parts have to match factory geometry...but then again...i don't know much. please help? thank you!
No. Don't do it.
The V+ is not designed to work with a spacer. There is an internal center support column in the middle of the V+. This column is meant to give the upper panel of the plenum the needed support when the plenum is under vacuume.
The top panel area of the V+ is (approximatly) 1 square foot in total surface area, or approximatly 144 square inches. When you have a vacuume in the plenum, the atmosphere will press a force of approximatly 5-10 psi on every square inch of the plenum. ...or up to 1440 pounds force of atmospheric pressure will be pressing down on the upper panel of the V+ plenum.
It is this force that requires the V+ to have a central support column.
If you put a spacer on, you will lift the outer circumfrence of the V+ plenum but what about the central support column? ...it will no longer be supported by the lower plenum it normally sits on. The V+ central support column will simply be lifted of the surface of the lower plenum and will no longer offer any structural support to the upper panel.
So the next time a vacuum forms in the plenum, the upper panel will have 1440 lbs force applied to it and the unsupported panel will be "sucked down" , bent, stressed, or deflected in a way that it was never menat to be.
This may work OK for a while, but after several cycles of vacuume/pressure deflection and stress, it is a problem waiting to happen. Eventually the unsupported plastic plenum will implode.
IE - This is not something you want to happen to your engine
...and especially not something you want to happen while you are driving.
You could do it if you can devise a way to keep the upper panel supported, but why bother. Its not worth the effort. Use it in the way it was designed for.
The V+ is not designed to work with a spacer. There is an internal center support column in the middle of the V+. This column is meant to give the upper panel of the plenum the needed support when the plenum is under vacuume.
The top panel area of the V+ is (approximatly) 1 square foot in total surface area, or approximatly 144 square inches. When you have a vacuume in the plenum, the atmosphere will press a force of approximatly 5-10 psi on every square inch of the plenum. ...or up to 1440 pounds force of atmospheric pressure will be pressing down on the upper panel of the V+ plenum.
It is this force that requires the V+ to have a central support column.
If you put a spacer on, you will lift the outer circumfrence of the V+ plenum but what about the central support column? ...it will no longer be supported by the lower plenum it normally sits on. The V+ central support column will simply be lifted of the surface of the lower plenum and will no longer offer any structural support to the upper panel.
So the next time a vacuum forms in the plenum, the upper panel will have 1440 lbs force applied to it and the unsupported panel will be "sucked down" , bent, stressed, or deflected in a way that it was never menat to be.
This may work OK for a while, but after several cycles of vacuume/pressure deflection and stress, it is a problem waiting to happen. Eventually the unsupported plastic plenum will implode.
IE - This is not something you want to happen to your engine
...and especially not something you want to happen while you are driving. You could do it if you can devise a way to keep the upper panel supported, but why bother. Its not worth the effort. Use it in the way it was designed for.
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Joined: Aug 2006
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From: Irvine
wow, thanks so much man. I didn't consider pressures. And seeing as I'm interning in an Atmospheric Space Physics pressure lab...I feel slightly embarrassed, haha. Anywho, could I potentially lengthen this supporting column with a material which has equal or greater tensile strength? seeing as the rise is only 5/16th's of an inch, it seems as if it wouldn't be too difficult. motordyne doesn't have such a supporting column, right? thanks again.
It's either one or the other....both are not needed.
The Motordyne spacer lifts the OEM upper plenum to increase the volume inside. The Kinetix is a complete replacement upper plenum that is taller than the OEM upper plenum.
Now the reason many do not like the Kinetix plenums are because their previous models may have not yielded enough volume increase or they may have been too weak to withstand the pressures involved. These issues were supposedly corrected with the latest V+ model. I will be honest, I have been going back and forth myself on whether to get the Kinetix or just go for the tried and true, dyno proven Motordyne spacer. The look of the Kinetix is nice, I don't care about keeping the stock look under the hood.
The fact that a Motordyne rep gave you an honest opinion above and didn't try to sway you from getting the Kinetix speaks highly of his character. Kudos to Hydrazine!
The Motordyne spacer lifts the OEM upper plenum to increase the volume inside. The Kinetix is a complete replacement upper plenum that is taller than the OEM upper plenum.
Now the reason many do not like the Kinetix plenums are because their previous models may have not yielded enough volume increase or they may have been too weak to withstand the pressures involved. These issues were supposedly corrected with the latest V+ model. I will be honest, I have been going back and forth myself on whether to get the Kinetix or just go for the tried and true, dyno proven Motordyne spacer. The look of the Kinetix is nice, I don't care about keeping the stock look under the hood.
The fact that a Motordyne rep gave you an honest opinion above and didn't try to sway you from getting the Kinetix speaks highly of his character. Kudos to Hydrazine!
Originally Posted by Hydrazine
No. Don't do it.
The V+ is not designed to work with a spacer. There is an internal center support column in the middle of the V+. This column is meant to give the upper panel of the plenum the needed support when the plenum is under vacuume.
The top panel area of the V+ is (approximatly) 1 square foot in total surface area, or approximatly 144 square inches. When you have a vacuume in the plenum, the atmosphere will press a force of approximatly 5-10 psi on every square inch of the plenum. ...or up to 1440 pounds force of atmospheric pressure will be pressing down on the upper panel of the V+ plenum.
It is this force that requires the V+ to have a central support column.
If you put a spacer on, you will lift the outer circumfrence of the V+ plenum but what about the central support column? ...it will no longer be supported by the lower plenum it normally sits on. The V+ central support column will simply be lifted of the surface of the lower plenum and will no longer offer any structural support to the upper panel.
So the next time a vacuum forms in the plenum, the upper panel will have 1440 lbs force applied to it and the unsupported panel will be "sucked down" , bent, stressed, or deflected in a way that it was never menat to be.
This may work OK for a while, but after several cycles of vacuume/pressure deflection and stress, it is a problem waiting to happen. Eventually the unsupported plastic plenum will implode.
IE - This is not something you want to happen to your engine ...and especially not something you want to happen while you are driving.
You could do it if you can devise a way to keep the upper panel supported, but why bother. Its not worth the effort. Use it in the way it was designed for.
The V+ is not designed to work with a spacer. There is an internal center support column in the middle of the V+. This column is meant to give the upper panel of the plenum the needed support when the plenum is under vacuume.
The top panel area of the V+ is (approximatly) 1 square foot in total surface area, or approximatly 144 square inches. When you have a vacuume in the plenum, the atmosphere will press a force of approximatly 5-10 psi on every square inch of the plenum. ...or up to 1440 pounds force of atmospheric pressure will be pressing down on the upper panel of the V+ plenum.
It is this force that requires the V+ to have a central support column.
If you put a spacer on, you will lift the outer circumfrence of the V+ plenum but what about the central support column? ...it will no longer be supported by the lower plenum it normally sits on. The V+ central support column will simply be lifted of the surface of the lower plenum and will no longer offer any structural support to the upper panel.
So the next time a vacuum forms in the plenum, the upper panel will have 1440 lbs force applied to it and the unsupported panel will be "sucked down" , bent, stressed, or deflected in a way that it was never menat to be.
This may work OK for a while, but after several cycles of vacuume/pressure deflection and stress, it is a problem waiting to happen. Eventually the unsupported plastic plenum will implode.
IE - This is not something you want to happen to your engine
...and especially not something you want to happen while you are driving. You could do it if you can devise a way to keep the upper panel supported, but why bother. Its not worth the effort. Use it in the way it was designed for.
https://my350z.com/forum/showthread.php?t=290120
again, i'm not saying that it will do anything beneficial...i just thought of this piece when i read the thread. if i was u, i'd just get the md spacer and scratch getting the plenum (but thats just my expert noob opinion)
Originally Posted by Sholmes555
wow, thanks so much man. I didn't consider pressures. And seeing as I'm interning in an Atmospheric Space Physics pressure lab...I feel slightly embarrassed, haha. Anywho, could I potentially lengthen this supporting column with a material which has equal or greater tensile strength? seeing as the rise is only 5/16th's of an inch, it seems as if it wouldn't be too difficult. motordyne doesn't have such a supporting column, right? thanks again.
But I still didn't feel comfortable doing it.
The plastic seems like its a glass fiber filled polymer... and as such, its strong and hard, but its also slightly brittle. Maybe its not a problem, but when putting a screw into the plastic, it puts a radial strain on the plastic central column.
I didn't feel comfortable about it because there is a potential for cracking the column. My friend really wanted to install both on his car, but it was forcing the plenum to do what it wasn't designed to do.
The spacer was later removed due to clearance issues with the hood anyways.
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Thread Starter
Registered User
Joined: Aug 2006
Posts: 23
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From: Irvine
dude... +1000 to Hydrazine for being honest and a awesome dude. Trust me, if i had the money, I would've loved to get the mrev2. but hey..maybe in awhile i'll still get it. in all honesty, thanks a lot for the detailed explanations. i'll look to you for future advice.
