Question about DW fuel pump maximum pressure - low?

[DSEROVY]

Okay guys, here's what I have-
I haven't played with the powerlogger or really leaned on the throttle since the late Fall. I had a few spare moments to play over the weekend so I logged a 3rd gear wide open blast.

Imagine my surprise when I reviewed the log and found inj duty cycle at 106% and wideband fuel correction maxed out at 30%!
On my last run in the fall, the Duty cycle was at 80% with 0-9% wide open fuel correction correction on a 10.80 pass with no traction.

I'm running a TT SD chip, 60lb injectors and a hot wired DW pump that I just bought from G-body in the Fall to replace a noisy (to me) Walbro. Turbo is a bb 6776 at 27 psi. I actually put WOT timing at 16 degrees to make sure she didn't have any cobwebs left over from the winter.

Luckily, I have a Alkycontrol dual nozzle system and I cranked it all the way up before I floored it, so I logged ZERO knock retard. Whew. Thanks Julio.

I'm running a hood mounted fuel pressure gauge, with base pressure set at 43psi. I installed my rail gauge and got the same pressure. I "think" it's rising at 1:1 with boost, but it's hard to stare at a hood gauge on a 10 sec car! I really need to install a transducer to log fuel pressure.

So heres my question -
What should the DW pump be able to put out if-
1)Car is not running (car runs, just not started!)
2) using the jumper lead behind the alternator to power up the pump
3) Accufab regulator screw turned all the way in?
- I'm now reading 70 psi maximum on the gauge at the rail doing it this way.

I figure 43 psi base + 27 psi boost = I NEED 70psi of fuel pressure, but that's also with 6 injectors sucking in high test at 6k rpm. Not alot of room for error here.

I really don't feel like dropping the tank again, and I'm just tempted to install a Racetronix double pumper in there if (when)I do. I had to fidget the pump around on the hanger on install, and still ended up with a goofy bend on the hose. I'm thinking it might be leaking inside the tank at the pump?

Also, how often do the Accufab regulators need rebuilt?

Thanks in advance guys.

 

[S10xGN]

I was able to test my Aero-340 to over 100# using these steps...

 

[TurboBuRick]

I just replaced a DW pump that was only a year old with a few hundred miles. The pump did build 100psi on a test but fell on it's face when trying to move volume. Junk it. Wright it off. It's a paper weight.

The new Aeromotives are looking good.

RL

 

[Mr.Spool]

i had a similar issue recently at the track,my fp was dropping at wot,i was spraying 150psi m10 and m15 so it didn't hurt anything and i wasn't running it that hard.i replaced the pump with a new one and wot fp went over 70 psi,you need to make sure you are seeing wot pressure and proper volts.i prefer to in car or a hood mount gauge for real time data,logging is only after the fact.

 

[Mr.Spool]

i switched to the jays racing pro-series,and it makes more pressure than anything i have used so far.

 

[Nick Micale]

Pump output will depend on voltage at the pump, have you measured it there?

 

[Pronto]

Also check your volts with the Powerlogger to see if they are dropping too much as the rmps go up.

 

[TurboBuRick]

Pump output will depend on voltage at the pump, have you measured it there?

No need for me to go that far. A hose off the rail into a gas can told the story crystal clear. JUNK!

RL

 

[DSEROVY]

Thanks for the responses guys!
Nick - I haven't measured voltage at the pump, but on my logs the voltage is the same from the 10.80 run I logged and from the weekend - steady 13.0 volts.
I would like to have more volts to the pump, but don't want to run a booster with the meth (right?).

 

[Nick Micale]

Just because your alt is putting out 13 volts, this does NOT mean you have that voltage at the pump.

We have seen only 7.4 volts at the pump connector w/o a hot wire kit, and most stock TR's will show only 10 volts there?

We do both, a hot wire kit and a volt booster.

 

[DSEROVY]

Local speed shop had a Aeromotive 340 on the shelf, just installed it - I'll let you know!

 

[BEATAV8]

I just replaced a DW pump that was only a year old with a few hundred miles. The pump did build 100psi on a test but fell on it's face when trying to move volume. Junk it. Wright it off. It's a paper weight.

The new Aeromotives are looking good.

RL

This is the first failed DW I've heard about. Got me a bit concerned about the one I'm using.....

 

[John Larkin]

I just replaced a DW pump that was only a year old with a few hundred miles. The pump did build 100psi on a test but fell on it's face when trying to move volume. Junk it. Wright it off. It's a paper weight.

My DW pump has a 3-year warranty. Why would you junk a replaceable pump?

 

[coach]

Someone better get ScotW in on this thread. He is the dealer. Richard Clark tested the DW and it passed his tests.

Coach

 

[TurboBuRick]

My DW pump has a 3-year warranty. Why would you junk a replaceable pump?

I didn't throw it away. I still have it if Scott wants it.

 

[Pronto]

It should be sent back for them to check. Might be a fluke or something more...

 

[Nick Micale]

I just replaced a DW pump that was only a year old with a few hundred miles. The pump did build 100psi on a test but fell on it's face when trying to move volume. Junk it. Wright it off. It's a paper weight. RL

With all the DW pumps Brian, Scott and myself have sold, and the many I have installed, only one had a reported problem?

This pump was returned and tested fine, it was actually installed in another car that still has no issues. The problem was not with the pump, but the installation.

I will be happy to pay you for shipping the pump to me for testing, and will replace it if it is bad.

As I recall, last year when Richard Clark tested a DW pump I supplied, it ran continuous at 16 volts for almost 2 days. The pump output was better than any in-tank pump he had tested.

 

[CGASTON]

Just because your alt is putting out 13 volts, this does NOT mean you have that voltage at the pump.

We have seen only 7.4 volts at the pump connector w/o a hot wire kit, and most stock TR's will show only 10 volts there?

We do both, a hot wire kit and a volt booster.

Nick,

Need your opinion... What do you think of those alternators (thread on here about them) that have an adjustable regulator built in. You are suppose to be able to adjust voltage 13-18v. Now this is almost the same thing except the the volt boosters are turning up voltage at a defined moment. And I would suspect that the alternator is supplying constant. But now with an alternator like that and a hotwire kit... You should be able to supply good amount of fuel.

Only issue I see is that you take a chance of burning up components on your system. Specially risky for ecm.

p.s. What brand of volt buster? Caspers or Reds?

Sent from my iPhone using Turbo Buick

 

[TurboBuRick]

With all the DW pumps Brian, Scott and myself have sold, and the many I have installed, only one had a reported problem?

This pump was returned and tested fine, it was actually installed in another car that still has no issues. The problem was not with the pump, but the installation.

I will be happy to pay you for shipping the pump to me for testing, and will replace it if it is bad.

As I recall, last year when Richard Clark tested a DW pump I supplied, it ran continuous at 16 volts for almost 2 days. The pump output was better than any in-tank pump he had tested.

Mr. Micale,

I would be happy to ship it back. Let me test it one more time. I want to see if it acts the same way out of the car.

RL

 

[Chuck Leeper]

Just because your alt is putting out 13 volts, this does NOT mean you have that voltage at the pump.

We have seen only 7.4 volts at the pump connector w/o a hot wire kit, and most stock TR's will show only 10 volts there?

We do both, a hot wire kit and a volt booster.

What Nick said..........

Check the ohms on the ground side, and check volt drop on all circuits, too!!