[_zaclemore]

SOLUTION: STACK 2 O-RINGS ON THE FEED BARB.


Decided to install my Radium parts today, or yesterday I should say, and I ran into a huge issue. It was designed to replace the fuel feed from a Lotus originally, but they used the Toyota fuel pump hanger design from 1996-onward. The same one the I/GS300 uses. It should be fine but mine leaks like a sieve. They even show a GS300 fuel pump hanger on their page.

This is the piece: Fuel Pump Adapter for Toyota Hangers

I like the rail and fuel pressure regulator, but this is a no go for me. Not too sure what to do because I was depending on this to actually work.

Any suggestions?

 

[_zaclemore]

Found the fix a beer later: double O-ring like the factory did. The OEM fuel line uses a black and a green O-ring separated by blue plastic spacers. Disassemble it to find these parts then stick an O-ring of your choice down on the male end of the fuel pump hat. Then install the Radium adapter to squish the O-ring at the bottom. It seems like it's holding up well for me, but I will update.

The single O-ring is not enough.

 

[Kris OK]

Man I had the same thing happen to me with one of their ORB swivel fittings. I put it on their fuel rail for the feed side. Put the intake back on and all the charge pipes n what not. That thing sprayed fuel like crazy. They sent me a new one but I was done with it by that point. Cool concept but garbage execution. Went with an Earls or Russel swivel.

 

[_zaclemore]

Man I had the same thing happen to me with one of their ORB swivel fittings. I put it on their fuel rail for the feed side. Put the intake back on and all the charge pipes n what not. That thing sprayed fuel like crazy. They sent me a new one but I was done with it by that point. Cool concept but garbage execution. Went with an Earls or Russel swivel.

View attachment 143723

It sucks that you need to use this if you have a VVTi motor. I'll update my thread with pics, but I put a -8 ORB to -8AN and a -8AN 90° coming off the front and it's only not touching because my injectors are taller than normal. It's insane they sell this incomplete product. The rail comes with injector adapters, but no block offs for the other feed ports. Then you pretty much need the DMR because that's their only good idea. I'm over it.

 

[Kris OK]

update my thread with pics

I’ll look for them. I’m a visual learner and can’t see in my head what you’re describing. On my rail the feed comes in on the firewall side thru the swivel adapter. The return goes thru a 180* AN (out the opposite end) then AN hose parallel to the rail and wraps around the IM plenum to the FPR (it’s bolted to the IM near where the oil dipstick is bolted). I think I have a Radium pulse dampener on one of the open ports of the rail.

 

[Hodgdon Extreme]

This is very disheartening feedback about Radium. I bought their fuel rail, pressure reg, pulse damper and a swiveling ORB. I've only done a mock-up assembly with them and everything seemed nicely made and fit together great... But I've not hooked everything up and actually pressurized the system. Hope it all works!

 

[Kris OK]

very disheartening feedback about Radium

I’m pleased with the fuel rail and the cam cover swivel ports. The orb fuel swivel may be fine after they replaced it, but I couldn’t trust it. They said there was a bad batch that got sent out, and I got one of them. It’s a lot of work to get to and put back together. So I was not getting bit twice by the same dog lol. The fuel pulsation dampener works well I guess? I don’t know how you’d even test it?

 

[Hodgdon Extreme]

I don’t know how you’d even test it?

Youd need to compare high speed (5kHz+) transducer data of fuel pressure with and without the damper installed.

I don't know how good or bad the radium part is, but the OEMs always include a pulse damper for a reason!

 

[_zaclemore]

Youd need to compare high speed (5kHz+) transducer data of fuel pressure with and without the damper installed.

I don't know how good or bad the radium part is, but the OEMs always include a pulse damper for a reason!

Right, I believe that it's for fuel pressure stability at high pressure or something. I don't believe they're necessary on low power cars, but on a sportscar I would understand the concern. On my Intelligent Sports car I do not care to use one.

I also have to say the Radium fuel rail and fuel pressure regulator are very nice pieces and I was lucky that my 90* fitting didn't leak on the first try like Kris. Adding a second O-ring seems to have fixed it, but my return line is leaking now lol. I should never have to modify an engineering company's product.

 

[AlwaysBroken]

I should never have to modify an engineering company's product.

“Engineering company” …sure. Nothing they sell is sophisticated imo. They fit the niche aftermarket and make a bunch of useful products.

To add to this Radium experience, the air assist adapter seats for the 2JZ they sell has an oversized O-ring. And it’s made for the 2JZ. It’s twice as expensive as the Driftmotion one but I’m willing to bet the Driftmotion ones probably fits better.

The pieces are very nicely made though.

 

[_zaclemore]

“Engineering company” …sure. Nothing they sell is sophisticated imo. They fit the niche aftermarket and make a bunch of useful products.

To add to this Radium experience, the air assist adapter seats for the 2JZ they sell has an oversized O-ring. And it’s made for the 2JZ. It’s twice as expensive as the Driftmotion one but I’m willing to bet the Driftmotion ones probably fits better.

The pieces are very nicely made though.

The DriftMotion ones are very nice and fit very well. Radium does excel in fit and finish. I said engineering company because they're called Radium Engineering lol, whatever they say.

 

[Hodgdon Extreme]

I believe that it's for fuel pressure stability at high pressure or something. I don't believe they're necessary on low power car

As injectors slam shut, they send a shockwave into the fuel rail that will reverberate until dissipated. As that shockwave bounces around in there, local regions of both high and low pressure will be created momentarily. If one of those regions coincides with one of the injector ports when that injector is open - the effective fuel pressure can be different than what the fuel map is calibrated for - resulting in more or less fuel delivered vs. intended.

The dude behind injector dynamics says this effect is exaggerated by big injectors.

The theory makes good sense - but it seems like the pulse damper would need to be uniquely tuned for specific applications; not just a generic one size fits all part. But as previously mentioned, us tuner nerds don't really have the tools or know how to test/tune something like this.

But what do I know?

 

[jesve]

Must be a Radium x Chase bays Collab am I right

 

[Kris OK]

Chase bays Collab

I’ve lusted after the CB power steering line/res kit…you saying to not bother?

I do have a CB clutch master cyl adapter. It’s pretty thin and flimsy but sandwiched between the CMC and the firewall probably beefs it up some. I shouldn’t have been a cheap ass and just got the Grannas kit for 279$ but damn that’s like 170$ for the billet piece cuz the Tilton CMC is only 109$ everywhere else. 😂

 

[_zaclemore]

As injectors slam shut, they send a shockwave into the fuel rail that will reverberate until dissipated. As that shockwave bounces around in there, local regions of both high and low pressure will be created momentarily. If one of those regions coincides with one of the injector ports when that injector is open - the effective fuel pressure can be different than what the fuel map is calibrated for - resulting in more or less fuel delivered vs. intended.

The dude behind injector dynamics says this effect is exaggerated by big injectors.

The theory makes good sense - but it seems like the pulse damper would need to be uniquely tuned for specific applications; not just a generic one size fits all part. But as previously mentioned, us tuner nerds don't really have the tools or know how to test/tune something like this.

But what do I know?

"In short, a pulsation damper does serve a purpose, but is not “necessary”. Many cars like the Mazda RX7 are equipped with a fuel pulsation damper that is prone to failing and causing an engine fire. If you plan on retaining the FPD you must keep an eye on it. Replace it BEFORE it fails and you loose your car to a fire."

Fuel Pulsation Damper

How a fuel pulsation damper works and why they are needed.

injector-rehab.com

My 10 second Google search aligns with my world view.

 

[AlwaysBroken]

I’ve lusted after the CB power steering line/res kit…you saying to not bother?

I do have a CB clutch master cyl adapter. It’s pretty thin and flimsy but sandwiched between the CMC and the firewall probably beefs it up some. I shouldn’t have been a cheap ass and just got the Grannas kit for 279$ but damn that’s like 170$ for the billet piece cuz the Tilton CMC is only 109$ everywhere else. 😂

I used $5 of drill bits and $10 worth of aluminum to make the adapter back when Grannas was one of the only options. Literally less than half the cost with the Tilton master. It’s a stupid piece of aluminum with some holes cut for the bolt and clutch master. For $40 for the Chase Bay one (unless I’m looking at it wrong), it’s certainly the far better option. The majority of the stiffness of the clutch master assembly will be from the clutch pedal assembly and not the firewall itself. The thick Grannas piece does nothing but add bling, weight, and a minuscule amount of stiffness.

For reference my manual brakes that’s currently only mounted to the firewall deflects 0.040” at the end of the MC. That’s using enough force to lock the wheels/activate ABS. I am doubtful that a clutch master which sees far less force will deflect more than that. I could be wrong but I really don’t think so.

That power steering res/line kit sure has a steep price…it’s not like any of the lines are high pressure. It’ll look nice if that’s the deciding factor.

"In short, a pulsation damper does serve a purpose, but is not “necessary”. Many cars like the Mazda RX7 are equipped with a fuel pulsation damper that is prone to failing and causing an engine fire. If you plan on retaining the FPD you must keep an eye on it. Replace it BEFORE it fails and you loose your car to a fire."

Fuel Pulsation Damper

How a fuel pulsation damper works and why they are needed.

injector-rehab.com

My 10 second Google search aligns with my world view.

A lot of things aren’t necessarily necessary lol. The FPR acts as a pseudo FPD so that’s probably why the aftermarket doesn’t see that much of a problem. It’s also not impossible for the home gamer to get a rough estimate of the fuel pressure pulses in their cars. Here’s a few sources I’ve found from googling:

https://www.diva-portal.org/smash/get/diva2:1392729/FULLTEXT01.pdf

https://www.researchgate.net/publication/273077264_Analysis_of_pressure_wave_dynamics_in_fuel_rail_system/fulltext/59963f2eaca27283b11beb1b/Analysis-of-pressure-wave-dynamics-in-fuel-rail-system.pdf?origin=publication_detail

They are for high pressure fuel systems but the underlying principle is using a 1D wave equation. Though I’m being a little cheeky since if you can understand whatever info is in those articles, then you would be telling me about fuel pressure pulses 😂

 

[Kris OK]

It’ll look nice if that’s the deciding factor

That’s the decider…looking good. I’ve thought about just getting the PHR pump adapter so I can run a Teflon AN hose from the res to the pump. I have just a ATF - compatible rubber hose right now, but it sweats ATF so I’m not sure how compatible it really is 😂. There’s a guy that sells the high pressure line from pump to rack on FB for like a benji. Then I could use another AN from rack to res ( I deleted the PS “cooler” loop years ago. It’s just: how easy is it to buy an off the shelf solution VS piecing my own together? But then you get into these situations like @_zaclemore where the fancy custom off-the-shelf part just pisses you off because it just_doesn’t_work like it’s advertised. So you wished you’d just DIYed it. I mean I’ve got a manual mill and a lathe and could make just about whatever, but I never have enough time to do what I want 😆

 

[AlwaysBroken]

but I never have enough time to do what I want 😆

The hidden cost of DIY.

I used a Acura TL res for my relocation so I didn’t put in much effort in making it look nice other than just making it work. Granted, the usual spot for aftermarket PS relocation is preoccupied so nothing on the market will work. Buying the reservoir but making your own lines might be the better way to go if there’s atypical things in your build.

Regarding the rubber hose, it really shouldn’t be sweating. My PS return hose hasn’t so far. The heater hose one definitely did. If you got it from Autozone/oreilly/etc be sure to confirm it’s a PS hose and not a heater hose. They all seem to think it’s equivalent like when they try to give me a fuel hose rated for 50psi. Literally nothing in the last decade uses a fuel hose with a 50psi rating.

 

[_zaclemore]

A lot of things aren’t necessarily necessary lol. The FPR acts as a pseudo FPD so that’s probably why the aftermarket doesn’t see that much of a problem. It’s also not impossible for the home gamer to get a rough estimate of the fuel pressure pulses in their cars. Here’s a few sources I’ve found from googling:

https://www.diva-portal.org/smash/get/diva2:1392729/FULLTEXT01.pdf

https://www.researchgate.net/publication/273077264_Analysis_of_pressure_wave_dynamics_in_fuel_rail_system/fulltext/59963f2eaca27283b11beb1b/Analysis-of-pressure-wave-dynamics-in-fuel-rail-system.pdf?origin=publication_detail

They are for high pressure fuel systems but the underlying principle is using a 1D wave equation. Though I’m being a little cheeky since if you can understand whatever info is in those articles, then you would be telling me about fuel pressure pulses 😂

Once I saw the integrals pull up I actually laughed. Jesus. I noticed these are high pressure diesel applications as well. Ya see, my car only SOUNDS like a diesel. Believe it or not, it's actually just a 2J crying for help.

I used a Acura TL res for my relocation so I didn’t put in much effort in making it look nice other than just making it work. Granted, the usual spot for aftermarket PS relocation is preoccupied so nothing on the market will work. Buying the reservoir but making your own lines might be the better way to go if there’s atypical things in your build.

I should do the MR2 or Volvo electric power steering pump. My entire car from day one could be considered "atypical." In fact, everything I do is atypical. If I'm going for the clean look, a remote mounted PS system might be just what I need...

 

[jesve]

I’ve lusted after the CB power steering line/res kit…you saying to not bother?

I do have a CB clutch master cyl adapter. It’s pretty thin and flimsy but sandwiched between the CMC and the firewall probably beefs it up some. I shouldn’t have been a cheap ass and just got the Grannas kit for 279$ but damn that’s like 170$ for the billet piece cuz the Tilton CMC is only 109$ everywhere else. 😂

I've got no expirence with CB but have heard they aren't great. Don't take my word for it, but personally If there is another option I will go with that. You know?