[urq] UrQ Fuel delivery fix challenge!

[Peter]

Ditto........

        Ben, I in no way meant to take away from your solution to the issue
and if it came off that way I offer my sincere apologies. I just offered it
as an FYI; not a more viable solution than yours.  Look, we all know that we
get absolutely no support from the mother ship concerning our URQS and the
only way to survive is with a free and open exchange of ideas to all the
issues so we can try and keep them together and running. Again, I applaud
your ingenuity and thank you for sharing it with us. Regards,    /Peter

On Mon, Mar 29, 2010 at 11:28 AM, <qshipq at aol.com> wrote:

>
>  Ben
> I never knock solutions that work!  I don't agree that the mounting of the
> anti-cavitation tank *needs* to be pre-pump in the urq.  That would only be
> the case if the fuel demand was a constant.  Can cavitation manifest itself
> at a bad time?  Sure.  And I applaud you for finding a solution with the
> noted challenge restrictions you self-imposed.  I don't see the solution to
> such a fueling issues as a 200$ fix.  Not for my own cars, or anyone elses.
>  Again, I'm glad you solved the problem, and did it with the constraints you
> put on your own view of it.  That's just cool Ben.  That's also not my view,
> nor the point of Peter's post.  I think we are both pointing out this isn't
> a new concept, and has been addressed the same, and differently, for many
> years.  If it solved the problem for you, that's all you need.
>
> Cheers
>
> Scott J
>
>
>
>
>
>
> -----Original Message-----
> From: Ben Swann <benswann at verizon.net>
> To: qshipq at aol.com
> Cc: urq at audifans.com; 'Quattro List' <quattro at audifans.com>
> Sent: Mon, Mar 29, 2010 12:10 pm
> Subject: UrQ Fuel delivery fix challenge!
>
>
> Scott,
> WRT the conversion of the UrQuattro to an EFI system which has reduced fuel
> pressure and greater flow, I'll issue a challenge, since folks seem to be
> pooh poohing my solution I did over two years ago as not being optimal.
> Regarding your comment regarding cavitation, space and mounting location is
> the main concern on the Ur Quattro.  Once the fuel is fed either by gravity
> or low pressure pump into a reservior with a large feed pipe, then
> cavitation becomes virtually a non issue.  Having the return flow teed into
> the surge tank pretty much eliminates negative pressure in the tank and
> sometime the fuel flow could reverse back into the main tank - great for
> keeping that sock clear of debris.
> I studied many variations on surge tanks, fuel cells, race delivery
> systems, anti-slosh systems.  Many were simply a large tank in the trunk
> with a small fuel cell in the engine bay.  Many of these systems were
> applicable to dead head or low return flow applications - like carburators
> mounted in Drag Race cars.
> In this case, the surge tank needs to come before the pump.  I considered
> using a low pressure carburator pump to draw fuel from the tank and pump
> into a surge tank, and I' tested it and it would have worked fine except for
> drawback of space and more complex wiring and plumbing.  Everything else was
> more expensive, too labor intensive, too much turnaround time, or space
> constrained and/or combination of the above.
> Simplicity prevailed in the end - nothing fancy and works great.  So maybe
> there is a better more effective way to solve the problem than what I came
> up with.
> The challenge, if anyone wants to go through the mental exercise and figure
> through all the caveats, is to have a fix to a constrictive fuel pump feed
> of 3/8" diameter with a slight kink from a tank that has a separate chamber
> at the bottom.  This feed essentiall starves pumps especially when the fuel
> pressure is dropped for EFI.
> The UrQ tank has a separate cavity at the bottom underneath another main
> bottom - so it is not a simple tank with one bottom, but a well integrated
> in the tank bottom where the feed line goes out.  The 3/8"  main feed line
> snakes into an 8" fine mesh sock located in the well chamber that is
> sandwiched under a first bottom.  You can't see the feed line because it is
> inside the sock and inside the well  - the hole to the well is about 2" dia.
>  The return line goes into the tank in different location in the tank than
> the main feed line - it diverges inside the tank.
> Well put some contraints on the challenge - these were essentially my
> constraints :
> The job needs to be completed within 2 days - start to finish.  That is the
> car can be out of service for two days max.
> There are no local welding shops that  will work on the tank and you live
> in an area with high labor premium where the cheapest labor is $35/hour.
> You can do you own welding, but cost of welding materials needs to be
> factored into the cost.
> You can use if on hand, a MIG welder  or torch, but no TIG unless purchased
> inside the $200 price. (If anyone knows where to get a TIG for $200 I'd sure
> like to know.)
> Incinerating or Blowing yourself up in process of welding does not count!
> Shipping a fuel tank is restricted as hazardous cargo.
> Fuel cell is acceptible fix, but must have 80% of the capacity of the
> original 22 gal. tank.
> The fix needs to fit in the same space as the original tank and consume no
> less trunk space.
> The fix needs to fit in trunk, engine bay, or  under the car in very
> limited space, and have ground clearance higher than the max travel of
> control arms and exhaust.
> Know that the feed lines from the stock tank are barely accessible - a 60
> deg. Bend in 3/8" feed pipe that is only 4" long coming out of a 5" dia.
> Hole in the trunk above the rear differential.  The return line is smaller -
> 1/4" I think.
> The distance between the tank feed line and pump inlet is 15" and the path
> is not direct - there is subframe, trans. Mount. Obstructing the original
> line feed path from tank to pump, so existing plumbing take a convoluted
> route..
> It needs to be safe - location can not be in proximity to any portion of
> exhaust.
> Total cost of the fix needs to cost under $200 including parts and labor.
> Extra points to solutions that retain original tank and plumbing from the
> pump to the engine bay connection fittings.
> Solutions that cost more will be considered too, since I would have paid
> more if I needed to.
> I did it with under $100 parts and 8 hours labor with one day down time.
> Let's see what folks come up with.
> Ben
> [Date: Mon, 29 Mar 2010 12:09:37 -0400
> From: qshipq at aol.com
> Subject: Re: [urq] urq Digest, Vol 77, Issue 35
> To: audionly at gmail.com, cody at 5000tq.com
> Cc: urq at audifans.com, mdeltergo at hotmail.com
> Message-ID: <8CC9D715D08AF11-1F34-2A10 at webmail-d049.sysops.aol.com>
> Content-Type: text/plain; charset="us-ascii"
> I agree with Peter, cavitation can be addressed before or after the pump.
>  Actually anywhere between the tank and the fuel rail.  This 'fuel
> capacitor' concept certainly can be mounted before the pump as Ben did it,
> but every HP application of this concept I've seen, is in the engine bay,
> regardless of pump location.  I would surmise the reason for this more
> common application, is less of a need to modify fuel tanks, fuel line
> diameter, and/or the risk of hanging a secondary fuel bomb under the car.
> Scott J]
> Original Post that started this all:
> [Date: Fri, 26 Mar 2010 12:21:43 -0700
> From: AF <afinn1 at gmail.com>
> Subject: [urq] More Weird UrQ Behavior
> To: urq <urq at audifans.com>
> Message-ID:
> <ed47d8be1003261221w2a4c5064v1f7af3a500956166 at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
> So, at the past 2 track events I've attended with my V8 UrQ I have had a
> weird issue with engine cutout at high rpms, usually in 3rd gear, but on the
> straightaways in 4th gear. They seem to occur during any throttle position,
> like cresting a hill, or accelerating out of a corner, which is somewhat
> unnerving. There are no fault codes thrown at all, which makes me think it's
> a fuel supply issue. Here's the weird thing, I would say it a fuel pump
> relay issue, but wouldn't the engine stall (that's what my old UrQ and Coupe
> GT would do on the highway), but in this case there's no power until I
> depress the clutch after slowing a little and downshifting, then the power
> is all back. The engine never stalls and shuts off! I confirmed it's not a
> rev limiter issue by redlining with moderate throttle input and no issues
> occured. It's definitely at higher RPM though. Does anyone have a thought? I
> thought about relaying the fuel pump, but wouldn't the engine simply stall
> with no fuel supply, or will it simply keep running with the car in motion
> and clutch out without shutting down or turning on all the warning lights on
> the dash?
> Any help is appreciated. Thanks.
> Andrew Finney
> 1985 UrQ 4.2L ABZ]
>
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