I've been experiencing a fuel starvation issue out of longer left handers since the car has been running, and I got the Radium fuel pump hangar in order to try and solve this. I haven't seen much news or posts about this hangar, so I figured I'd document my process with it and if it solves my fuel starvation issue.

To preface, I had already replaced the fuel sock with a new Denso sock and that solved the starvation issue for a day only. On the second day the starvation returned. There isn't any rust inside the tank, and the baffle is inside as well. I am using E85 with PTFE lined AN6 lines, DWFF110 filter, and a Continental E85 sensor plumbed in-line.

Final install with DTP and DT connectors for the fuel pump and fuel level sensor.



As it comes out of the box.



The two one way valves in the basket. Pieces of rubber with a nipple on them to keep them in place.


Basket that the fuel pumps and fuel pump socks live in.


Finished assembly. Replaced the barbed fittings with AN6 male swivel ends since thats what I have in my car. Radium provides a set of quick release fittings that adapt to the 89-97 cars, and the stock 99-05 fittings will work without any adaptation.



Markings and studs for brushless and brushed pumps.


Underside. Installed are the extension brackets for the pump hangar as well as the fuel level extension bracket for my 95 gas tank.



Fuel pump installed with the fuel sock inside the basket. the return tube also dumps straight into the basket.



Installed in the car. Was pretty difficult to maneuveure in there with the cage in the way, but it got into the tank when approached from the rear of the car and bringing it forwards.


Piece of green tape on the feed fitting and line so I don't mix them up. Not totally necessary, but it makes it very easy to ensure I hooked them up the right way. If i were to do it again, I'd do male for the feed and female for the return on the hangar side so its impossible to hook up backwards.



First heads up. There is no tool access to the studs when the hangar is installed in the car. The parcel shelf is over the hangar and I didn't trim mine so I couldn't use a socket. Also, the threaded studs utilize a 3/8" nut, the only SAE hardware on my car. I have only been bringing metric size wrench so a trackside pump replacement would be quite difficult with a 10mm, when even the correct size wrench doesn't fit. Theres enough clearance between each stud for sockets, but not wrenches. Additionally, you can't read the laser engraved labels on the outside edge of the hangar, so I just marked them in sharpie so I could check if things are wired correctly at a glance.



I had hooked up the pump and level sensor, but I didn't like how difficult it was to connect the wiring.


Placed the fuel pump on a DTP connector and the fuel level sensor on a DT connector—no chance of mixing up connections due to the different connector sizes and easy wiring disconnects.



I intend to test the car on track in late August and Thunderill East Bypass with lots of fast and long left handers, so a perfect place to see if this part will do what I expect it to. I'll update this thread with results and on-track experience later.

 

@rabid maybe this will fix your fuel starvation issues.

Chuckie how much fuel have you been running when experiencing fuel starvation?

 

Pretty much anything below half tank

 

I know of at least one person who tried this on their car and found that it did not fix their fuel starvation. Though looking at the pictures, the pick-up sock orientation looks different in your pictures than I saw in theirs. I wonder if they installed it wrong or something has changed.

 

I noticed you're using a DW pump. We just recently switched from a DW200 to a Walbro based on this thread where multiple track Miatas of various setups all had the same issue.

https://www.miataturbo.net/suspensio...arving-110121/

From my understanding - the DW doesn't have enough constant suction to keep the fuel sock full (acting as a fuel reserve) since it's a turbine based pump vs a positive displacement one. Turbine pumps are typically designed more for operating in a fuel bucket. The Walbro pumps are positive displacement pumps which are similar in function to the OEM Mazda pump.

 

yeah I saw that thread after I installed my hanger. I’m hoping that the bucket the pump is sitting in is enough to constantly keep fuel around it with the two one way valves in addition to the very direct return line. If this doesn’t work, I’ll probably be getting a Walbro pump

 

I asked about this hanger on one of the facebook groups and most reports were that it was far far worse on the fuel starvation side than a factory hangar. I decided to not spend the 600+ dollars on it.

During that conversation the stuff about the Walbro vs. DW fuel pumps came up and people were talking about the DW not being a PD pump. Most people in that thread said swapping from a DW to a Walbro basically fixed their issues. The other issue I think was the DW pump has a small hole in the bottom and the factory rubber isolator on the Miata hanger blocks that hole. Something about that hole was important on the DW pump, I think it was the priming hole or something like that, and if it was blocked the pump would constantly lose prime.

Good luck and hopefully things work out for you, but I wouldnt hold my breath...

The factory Miata hangers are known for sucking all the fuel down to like a liter or less, so fuel starvation issues in a Miata are pretty rare.

 

YMMV, but my money is on still having fuel starve issues. Source: I bought this day 1 and have fuel starve issues, probably worse than before. I tried the pump on both sides of the hanger. I have a surge tank sitting on the shelf waiting to plumb in.

 

I've seen that in a number of places now, DW vs. Walbro that is. I've never ran anything except Walbro, so I guess I'm lucky there. Radium "gave" my shop one of the hangers, I threw it on my car and haven't had any issues, although like I said I run a Walbro, and have only tracked it a couple of times. The way it's designed, I don't see how it could possibly be worse than factory unless it keeps fuel in the bucket during slosh, and simply doesn't refill fast enough for the next slosh.

 

Yeah, I wish I saw that thread earlier, but I already have the hangar and its in the car already so...
I'll probably be going to the track with a Walbro TIA485-2 in my spares kit. 450lph pump seems like a bit of overkill for 160hp though, I'm not gonna lie.


Also, not much popped up when I googled this part, so hopefully this thread is helpful for the ones who are looking around for fuel starve issues and thinking about this hangar. Facebook is always incredibly hard to access old info if you haven't seen it before.

 

Unfortunately, I’ll never know if the hangar will be the cause of a fix for me. The DW200 **** the bed through user error on my end, so I just replaced with a Walbro pump.

 

We always used Walbro pumps and never had fuel starve issues over probably 30 builds. That is unless the fuel sock had a pinhole then it would fuel starve. We have noticed that running a higher ethanol content make the socks wear out faster. Standard track spares for NA/NB included a new pump and sock among other things.

 

I went through 4 new denso fuel socks from RockAuto in 5 track days because I was experiencing fuel starve. I am using E85 exclusively, but none of the fuel socks were over 2 months old.

I do think I something else causing the issue because I was still experiencing fuel starve with the Walbro pump and the radium hangar so I'll have to take another look at the system as a whole.

 

If you have ever dropped a scope into an NA/NB tank, you'll see a slightly polished spot where the stock sock contacts the spot welded baffle plate. This is a cleverly engineered interface and why stock Miats can still turn at 1.2g with less than 1/2 gallon. If anything changes in your OEM based fuel stack to affect that interface, you run the risk of fuel starve. So a new pump with different dimensions, spacer, adapter or anything not exactly OEM orientation is to be avoided IMO. We learned this the hard way so every car built with non OEM fuel bits was checked to maintain that interface as OEM.

 

Well all my previous fuel starvation issues were with the stock NA hanger with a DW200 pump and new fuel socks in a stock fuel tank, so something clearly wasn't working for me. I still have that assembly so I can go back if needed.

 

So I'm going to be going back to the stock hangar. The Radium hangar isn't working for me, and its a pain to service at the track. It looks nice, but I just don't need to capacity of 2 pumps, and the 1 way valves just aren't working as I would have hoped.

 

Can you explain the check valve issue? I'm running one of these on my street car with zero issues, and put one in a 500hp turbo BP that solved a lot of issues. I get that installation of the wiring can be difficult, but I easily got a wrench on my wiring nuts, never had wires pull out, and really appreciate the various benefits and flexibility it offers.

I also think this forum is small enough to mention this, but because of the amount of product my shop buy's for customers from Radium, I got both of these for free, so money isn't as major a factor is it might be for others.

 

I'm still getting fuel starve when I'm below ~3gal in the tank after longer left hand corners of over 1g. I had hoped that the one way valves and bucket that the pump sits in would act as sort of a surge tank, but its not doing that for some reason. Maybe my fuel pump is overpowering the basket and pushing fuel out with the amount of flow, but I'm not really sure.

The wiring is fine, I don't really have any problem with the design, I fully admit that the wire pulling out of the terminal was a user error on my end. Even after that got fixed, I am still unable to run the tank empty, and have to keep at least 7-8 gal in the tank before every session. The cage I have in my car is in the way enough that I have to struggle to get the fuel hangar out every time, and it's not solving my fuel starve issue, so why keep it in the car.

While the piece isn't exactly cheap, I don't mind paying for product that works, but I bought it specifically to solve fuel starvation at high g with low fuel loads, and its not doing that. Its a super well constructed piece, and the ORB fittings for the AN lines are really nice.

If I still am unable to solve the starvation issues with OEM hangar, fuel sock, and walbro pump, I'm going to be installing a Radium surge tank.

 

Understandable, despite what they say I don't see how the bucket and little rubber flappers are a replacement for a proper surge tank.

Was this with a Walbro on the radium hanger or still a DW?

 

RockAuto sells shitty parts. they are notorious for that.