VDI and boost
#1
VDI and boost
I have noticed that many people keep the VDI closed when tuning with turbo applications
what would happen if it operated as normal?
Has anyone tried this?
the VDI is like a boost in an n/a app, but under FI could it still act as a boost, perhaps added 2 psi? or screw up flow?
what would happen if it operated as normal?
Has anyone tried this?
the VDI is like a boost in an n/a app, but under FI could it still act as a boost, perhaps added 2 psi? or screw up flow?
#2
no agenda
iTrader: (2)
I have noticed that many people keep the VDI closed when tuning with turbo applications
what would happen if it operated as normal?
Has anyone tried this?
the VDI is like a boost in an n/a app, but under FI could it still act as a boost, perhaps added 2 psi? or screw up flow?
what would happen if it operated as normal?
Has anyone tried this?
the VDI is like a boost in an n/a app, but under FI could it still act as a boost, perhaps added 2 psi? or screw up flow?
My understanding of the VDI is it takes advantage of the supercharging effect that is generated in the intake.
IIRC it goes something like this: Due to the compressibility of air, when the intake port begins to close the column of air begins to compress from the inertia of the moving air column. This creates a local high pressure wave, which travels back up the intake runner. The intake plenum is designed in such a way to take advantage of this (VDI) by forcing some of this pressure wave down the other intake runner to the other opening port.
Again IIRC from Jeff's webinar that forced induction ruins this effect so there is no need to deal with it and causing a lean/rich situation. Opening the VDI at 7500 rpm is likely to take psi away as that area of the intake now needs to be filled with air.
Last edited by wcs; 12-28-2011 at 10:51 AM.
#4
no agenda
iTrader: (2)
I'll go out on a limb here ....
How do we know the supercharging effect is ruined by a boost intake charge?
Is it possible that a 10psi column of air collapsing on a closing intake port could create a local pressure increase and send it back through the VDI to the other opening port?
Or does the small amount of leakage negate the effect?
/start Flame suit shield
How do we know the supercharging effect is ruined by a boost intake charge?
Is it possible that a 10psi column of air collapsing on a closing intake port could create a local pressure increase and send it back through the VDI to the other opening port?
Or does the small amount of leakage negate the effect?
/start Flame suit shield
#8
No respecter of malarkey
iTrader: (25)
lol, if MM is your tuner then what difference does it make?
It would appear that there isn't any need in opening it for FI, but it wouldn't hurt to try and see if it matters
ps: and I've been back to work, the new job is rockin', more so since it is usually dead this time of year
.
It would appear that there isn't any need in opening it for FI, but it wouldn't hurt to try and see if it matters
ps: and I've been back to work, the new job is rockin', more so since it is usually dead this time of year
.
Last edited by TeamRX8; 12-30-2011 at 09:46 AM.
#11
perhaps, however this topic is one that had no dedicated thread that I found from searching, and it seemed everyone suggested it to be closed. case closed, however my experience showed that leaving it open may either add benefits or could cause a local boost spike and detonation could occur.
A ton of info on tuning? I think not, there is enough info to hint at tuning but most of it is shrouded in trying to over-complicate it, or people just playing on, I know but I am not telling, or people pretending to know, or the people assuming that everyone learns the same way...
A ton of info on tuning? I think not, there is enough info to hint at tuning but most of it is shrouded in trying to over-complicate it, or people just playing on, I know but I am not telling, or people pretending to know, or the people assuming that everyone learns the same way...
#13
I appreciate your honesty I will admit I don't know as much as I could, and I am still learning, but I am not a complete dope, often times I over analyze a curtain point, which causes me to overlook other aspects, if there is something particular that you think may benefit me, some good searchable keywords would be great
Thread
Thread Starter
Forum
Replies
Last Post
JimmyBlack
Series I Major Horsepower Upgrades
273
02-10-2020 10:23 PM
yurcivicsux
Series I Major Horsepower Upgrades
192
09-12-2017 10:54 PM
05rx8mazda
RX-8 Parts For Sale/Wanted
18
11-28-2015 09:42 AM
JantzenRX-8
RX-8 Parts For Sale/Wanted
1
10-04-2015 11:30 PM