[urq] UrQ Fuel delivery fix challenge!
Ingo Rautenberg
ingo.rautenberg at gmail.com
Mon Mar 29 11:11:56 PDT 2010
Ben, I don't think anyone's doubting you. Your fix worked (and I remember
well your frustration when you were looking for a solution to your
problem). Maybe I missed the pics you mentioned earlier or you tried to
attach them and they got snipped. Do you have a link? A great discussion
as always. BTW, when did they enlarge the Urq fuel lines? Was that '84 or
for the later EFI models?
Ingo (without an Urq for the moment)
On Mon, Mar 29, 2010 at 2:07 PM, Peter <audionly at gmail.com> wrote:
> 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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> >
> >
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