making vortech fmu adjustable
#1
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making vortech fmu adjustable
The fmu increases fuel pressure in direct relation to boost pressure. So if one could restrict pressure at the fmu input, it would modify this relation. IE the stock 12:1 ratio could be modified to 6:1 if one could restrict 50% of the pressure signal.
So my plan is to source and install an adjustable pressure reducing valve before the fmu signal input, effictively creating an arfpr.
Could there be any issues with the prv in vaccum? Anyone try this?
Assuming I can find an approprate prv, I'll give it a shot this weekend.
So my plan is to source and install an adjustable pressure reducing valve before the fmu signal input, effictively creating an arfpr.
Could there be any issues with the prv in vaccum? Anyone try this?
Assuming I can find an approprate prv, I'll give it a shot this weekend.
#2
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A simple restrictor isn't enough, you'll need a variable bleed after the restriction, kind of like the cheaper MBCs. Wouldn't this tend to produce a fairly non-linear response curve however?
You can buy "recalibration kits" direct from Vortech to alter the pressure ratio. Here's a link to their page: http://www.vortechsuperchargers.com/.../fuel_fmu.html
You can buy "recalibration kits" direct from Vortech to alter the pressure ratio. Here's a link to their page: http://www.vortechsuperchargers.com/.../fuel_fmu.html
#3
Boost Czar
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You could probaby use a needle valve with a one way check valve on the end. but it's way easier to buy a recalibration disc. Takes about 5 minutes to swap, and chances are you can do it mounted, at least I can.
Last edited by Braineack; 10-06-2006 at 07:13 PM.
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A pressure reduce valve isn't a simple restrictor. It reduces pressure at a ratio IE it lets a determined portion of the pressure through and bleeds the rest. Maybe I've got the term wrong, but I think it's called a non sustaining pressure reducing valve.
A mbc would kind of "delay" the boost signal, probably creating a lean condition until it opens.
A mbc would kind of "delay" the boost signal, probably creating a lean condition until it opens.
A simple restrictor isn't enough, you'll need a variable bleed after the restriction, kind of like the cheaper MBCs. Wouldn't this tend to produce a fairly non-linear response curve however?
You can buy "recalibration kits" direct from Vortech to alter the pressure ratio. Here's a link to their page: http://www.vortechsuperchargers.com/.../fuel_fmu.html
You can buy "recalibration kits" direct from Vortech to alter the pressure ratio. Here's a link to their page: http://www.vortechsuperchargers.com/.../fuel_fmu.html
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Last edited by Ben; 10-07-2006 at 12:41 AM.
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Plus, I don't have the disks I want, and can't get them before I go to the dyno Monday.
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