Jeff, I thought that the pressure should be base pressure + map at that point in time.

I have emailed DW also but not holding my breath.

 

if you had enough pump, your fuel pressure curve should look exactly like your MAP curve.

where fuel pressure = base +MAP

yours takes a dump as soon as you hit boost, so either the regulator is leaking or the pump cannot handle the load. If it was a voltage issue, you'd be popping the fuel pump fuse in the kick panel.

 

The DW300 shouldn't have a problem supporting your setup. Did you contact DW through the website or did you email someone directly? I've sent you a PM.

 

After thinking about your last comment above I agree. I think there is only a 15 amp fuse on the fuel pump so high amp draw would pop it quickly.

Sounds like the pressure relief valve is faulty. Usually they open around 90psi or so (what walbro sets them at) but if there is a flaw yours might be leaking off pressure. No company has 100% quality control. There is bound to be a bad unit eventually and it sounds like you might have one.

 

mr rizk, i did not read through this thread, but i can tell you that DW fuel pumps are really bad.

I have had nothing but problems in

Subaru's mitsubishi's nissan's and latest the GTR and its a pain replacing those.

go for Aeromotive 340

 

All, Thanks for feedback. I fixed my vac leak issues and I know most of you said that it probably wont make a difference but it can't hurt to test. Hopefully I can get it back on the dyno soon to see if any changes.

@str8dum1 thx for the confirmation

@wannabuy350 to be honest it could be a pump issue as that hasn't been ruled out. Not dissing your comment but no matter what brand of pumps you search for there are failures. I agree the 350z is a pain to replace especially when you have a custom sub enclosure sitting in that space

Chris from DW has been kind enough to get in contact with me so hopefully with all the collective minds here i will have fix in the near furure

 

^best of luck, but in a GTR build that we did recently the customer provided the DW pumps and within weeks they stopped working, then he got them again. one week later not working. replaced with HKS pumps and never had an issue as its what i usually use in the GTR build.

I am not saying that DW is a bad unreputable company, its just that there are issues with their pumps and some injectors that i have encountered.

 

I don't think community members that post on forums realize how easy it is to make statements like this and not understand the potential harm it can do to a person or entities' livelihood.

Our products are one of the best performing in the industry and we are constantly making improvements. Taking a sample from the years our company was growing and trying new things and blanketing it upon what is currently offered completely negates the steps we've moved forward as a company and the fueling industry along with it.

My role within DW is support and R&D, and I can tell you that a majority of the time our pumps are "suspect" as a cause it is discovered later that the pump tests within spec and the installation or another component is found to be the issue. We are one of the easiest companies to get a hold of and I wished more people would give us an opportunity to correct an issue before turning to the keyboard.

I am currently working with Mr. Rizk to find a solution the problem he is experiencing.

 

My Dw Injectors and DW300 Pump Work Flawlessly......

Never a Problem in thousands and thousands of miles on the Street, and Drag Racing.

 

Quick update. As above I fixed the vac leaks and also installed the original IC. The reason I installed the smaller IC is because I was chasing issues with power at top end which I don't believe I experienced before.

Anyway here is the updated trace. Even though I had stable boost before the fuel pressure was dropping at high rpm. I believe fixing the vac leaks has helped the fuel pressure and brought the duty cycle under 80% which is what I originally targeted. I would be surprised if it was the IC.

Looks like I gained a solid 12psi increase and a flatter pressure curve. Will install the large IC and retest as my IAT are way to high with this IC.

 

looks perfect. now ramp up your duty cycle past 5000rpms to keep the boost curve flat or slightly increasing to redline.

weird that your boost curve before was normal while your FP dropped. so whatever you moved/ tightened fixed a leak to FPR

 

The leak was on the lower collector. I had a Cosworth phenolic intake manifold spacer and the sealant was leaking. I replaced with OE gasket and this fixed the leaks.

 

+1 on the DW post. Every company has an error rate so eventually there will be some products that fail. DW has always been an easy company to work with in my experience and would suspect they will go out of their way to fix a bad product in those rare cases.

That looks like good fuel pressure now. Apparently the vac leaks were causing loss of pressure at that FPR. I drilled and tapped my own 1/4" barb right off the back of the plenum so I had a dedicated source to my FPR. When I had it t-ed off of something else I was getting weird fluctuations and with a solid source I never have any problems.

Glad things are working better!

 

I am glad that you stand behind your product and help the community with any issue that arise. maybe if you can post what your system voltage requirements or recommendations, what causes fuel pump failure.

Basically a guidline that all can go by which would be better for you and the end user.

thanks, and i meant no harm honestly