Radium Fuel Pulse Damper Teardown and Test - Does it Work? Kinda does, just not as well as I hoped.

[@raeneshadow]

It might be better to just use a swirl pot / surge tank post filter pre rail... that should act as a big natural dampener and also cover up any temporary fuel drops due to low fuel.

[@GIZZMOTORSPORTS]

That sounds complicated. There isn't enough info on this topic. If I were to try something different I was thinking using a corvette returnless filter.

[@ahmed9399]

Thanks for posting this. I expected the fuel pressure line on the chart to be as smooth as the volts line... not sure if my expectations are realistic? Anyway, if its volatile at only very high rpms (and not everywhere) it may mean you may have another issue? Keep us posted

[@GIZZMOTORSPORTS]

I’d like to add another damper, but no room on my fuel rail. I’d have to buy the radium rail, may as well get their regulator and add the big damper. I’d have a total of 3 dampers, I’d like to try but don’t want to gamble the $$. I think it helped a bit, just didn’t work as advertised. This is what it looked like before the radium damper, kzbin.info5RTPiDW9jjw?si=HxVhZ1gsxqq5sEiw

[@Happydays-w3z]

great video and recent! i was just researching fuel pulse dampeners for a subaru ej25 build. trying to find relevant infrormtion to see if this is a requirment or not.

[@GIZZMOTORSPORTS]

Looking at my datalogs and the AFR, with the radium it does look a little better. The fuel pressure is still pulsing high and low. It's just a little better, not as good as I was hoping. But it's good enough that the AFR isn't going full lean over 8500 rpm, the pulses of course are not consistent so I just made it rich at high rpm. Do I add a 3rd fuel damper?? 🤔

[@bobbyhaskell2048]

I came looking for answers as well. I have the same thing going on with a 4 cylinder Nissan qr. Was thinking about trying that same damper. AEM 340 in tank pump radium regulator and a injector dynamics filter. Innovate ethanol content gauge with the content sensor on return line. Going to remove that as a test. Might move it feed side. The only thing besides changing fuel psi I have tried so far was add more volume between regulator and rail. Interestingly enough that made it worse.

[@bobbyhaskell2048]

Thank you for this content. Yeah not much out there for information about this. Every application will vary as well however just trying to get some insight and or ideas.

[@GIZZMOTORSPORTS]

@@bobbyhaskell2048 funny how the manufacturer doesn’t offer any data. You never hear anything from them. There is some install info on peoples KZbin channels but no data. Would this be your sole damper? Or are you adding it as a second?

[@theenterprisefilmz3728]

Would this be only for turbo applications or would an all motor N/A setup with upgraded fuel injectors benefit from this? Thanks!

[@GIZZMOTORSPORTS]

All engines should benefit with a damper, I suspect most cars would have pulsation issues at higher rpm, people just aren’t revving that high or looking for issues. The engine in the vid is all motor

[@drewdavis239]

Fwiw most fuel pressure regulators have a " return bypass orfice " if its a big hole it bypasses lots of fuel ( multiple pumps) it runs lower pressure at a given adjustment point with the big hole. If your single pump you use a smaller bypass. It adjusts easier and higher , less volume is bypaassed.... if your running the wrong orfice mabye its effecting your set up? Also if your return is a choke point it can do weird stuff. Stock venturi on a saddle style tank can be the restriction.

[@drewdavis239]

I just got off the phone with radium. (Sept 2023) They said they redesigned their fuel bypass orfice. And the diaphram some how. I blew my diaphram. Fwiw your diaphram with the ball bearing shouldent have the fraied edge aginst the metal oppisite the ball side? Hard to see not in my hands. My radium diaphram on my fpr (mpr) blew out and has a small area freyed like your but only a half inch long... yours looked freyed everywhere. Also i only had 300 miles of pump gas through mine,totally rotted out the gas side rubber into tiny squares... still worked but i had to crank the adjuster to get my base pressure over 50 psi with no reference line... i would buy a new diaphram for that freyed one at least

[@drewdavis239]

The radium fpr diaphram also has the ball... its just their dampner missing the ball. So they do apear to be the same. I do know if this new bypass orfice the ball sits on, combined with the new radium diaphram doesnt fix my base pressure im going to try a d.w. fpr. I cant believe how disintigrated my diaphram is after 2 tanks of 93 pump gas. Bought new from radium, been in the car less than a year. Radium said i should be able to adjust to 100 psi with a wb255. I cant get over 50 with a dw400. If i pich the return it goes to the moon ... lets hope this bad bach of diaphrams is the issue

[@drewdavis239]

Fwiw im running the radium mpr in a dead head set up like factory. ( turbo 3.2 m3, radium e46 kit ) imo you need to stretch out the diaphrams your using. Check for micro cracks on the gas side. The fabric will still hold some pressure but it will be inconsitant .

[@GIZZMOTORSPORTS]

@drewdavis239 I have had issues with aem diaphragm drying out. I now coat the dry side with silicone grease hoping it helps. what car and engine? Where is your pressure gauge or sensor located?

[@drewdavis239]

S52 e36 m3 motor. Fully built je pistons eagle rods. 6766 , 625 + 9to1, ape flex ,super tec.. dual maps , ect... radium mpr and glass filter in the stock location under the driver seat. System is dead head to the rail like stock. 3.5 bar like stock. . 6 id1050s all vibrant ptfe -6 everywhere. Dw400 with their wire /relay set up direct to the battery in trunk. Car is a e39 touring. I have a few quick videos😮

[@drewdavis239]

I tightend the diaphram till it was spring bind... backed off two turns. Still popped the diaphram, but it was degraded so bad im suprised it worked at all... dw400 seems ok. Does a lot of volume , does a lot of pressure. Ive heard a few people with weird pressure and flow issues on the radiim style diaphram.... i ordered the new orfice and diaphram for 45$ but i dont have high hopes it fixes my issues.

[@C.P.C.RACING]

Do you have a full tank of gas. Because you can get fuel spikes with 1/2 a tank our lower. It's best to run a surge tank. To prevent that spiking. Also make sure your running next size down on return line from your feed line.

[@GIZZMOTORSPORTS]

1/2 tank or lower? Really? I’ll have to fill up and datalog some runs. I’ve never noticed any fuel level issues so far, as long as I’m not on E. I actually experimented with a different size fuel return line, I went extra large then back to the tiny stock line. I am running an aem FPR with the smallest orifice, basically the same idea. AEM recommends to run the smallest orifice possible, so I’m doing that. I’m considering swapping a 255 pump back in and ditching the 340, after that maybe go to a smaller set of injectors. Unfortunately the injector wizard selection on my old aem series 2 is limited. I also want to experiment with not using vacuum reference on the damper and also the FRP, maybe intake pulses are throwing them off. Thanks for the comment.

[@C.P.C.RACING]

On the Dyno the AFR is stable. But when I would drive it with a half a tank or lower my AFR was all over the place. But when I fill the tank all the way up my AFR stabilizes.

[@GIZZMOTORSPORTS]

@@C.P.C.RACING I’ll have to try that, but not exactly ideal adding weight for the track. Your tank has a baffle?

[@peterthadeus9441]

Having erratic fuel pressure at 9,000RPM, lol.

[@iamjustanotherdude]

How did this end up eventually? Did you find the issue and how did you resolve it?

[@GIZZMOTORSPORTS]

No solution for this combination without swapping parts. I'd like to try smaller injectors and go back down to a 255lph pump. I may eventually do it, I'll 100% do it if I find a lighter chassis for this engine. Until then I dropped the rpm limiter from 9400 down to 9000. It's still bad above 8000rpm so I just increase the injector duty cycle to keep it overly rich and safe.

[@scottwinders9961]

The Radium damper you are using is intended for fuel pressures in the 40 - 70psi (static) range. If you are running less than that, how could it work?

[@GIZZMOTORSPORTS]

Running 60 static

[@scottwinders9961]

@@GIZZMOTORSPORTS That's not what your data trace shows....

[@GIZZMOTORSPORTS]

@scottwinders9961 I saw that too, looks bad. I’ll post some other tests. Where Honda measures the pressure at the fuel filter is higher than where the sensor is close to the FPR. I went ahead and drilled the inlet to the fuel rail to try and even it out. I just tried removing the vacuum source to the damper and it doesn’t swing as much but it still does. I want to do some more runs comparing damper port open to atmosphere vs capped.

[@vinceboyd7341]

Stock fuel lines? Maybe increase size to 6an or so

[@GIZZMOTORSPORTS]

Hmm, is that often helpful? That didn’t occur to me for this low hp engine setup

[@Blakelikesfood]

Not that you necessarily need MORE fuel, it's about fuel flow and REGULATING fuel flow. Surprisingly, the return line being too small messing everything up...everything. Sound ridiculous, but many times the return line is more important than the feed...because a pump forces, feeds, shoves fuel at the reg, even if the line is too small, yet the power, energy, pumping force is dismissal going back and you can't properly charge/maintain a steady psi without proper bleedoff. Get a ~30' roll of generic 3/8" rubber line, or 6AN hose and run from rail straight to tank tossing all the garbage pea shooter metal oem lines. Don't worry about all the AN fittings looking like a NASCAR when done you can simply do push barb (like factory) and look cleaner and don't have to mess with a ton of AN fittings (unless you want to go that route). I was able to slide 6AN lines directly onto the OEM fuel pump basket nipples with a hose clamp...sometimes ridiculous to over complicate things make it all chunky AN fittings.

[@GIZZMOTORSPORTS]

@@Blakelikesfoodi don’t remember the timeline but I actually did just that, because the return line appeared plugged. For some reason with the 3/8” line It didn’t make a difference in the datalogs so I just happened to try blowing through the oe pee shooter and it unplugged?? To I went back to stock, maybe I’ll revisit this. I now also have another diaphragm I can try.

[@Blakelikesfood]

@@GIZZMOTORSPORTS Fun isn't it? You also might consider selling your rail, for the Radium rail, as they generally place the dampeners in the middle. If you make a wave/ripple at one end of a pool it goes down to the end, comes back and say you can cancel/stop it there. Yet, it already went down and back didn't it? Yet another forms. You ARE canceling the wave, yet it's still traveling the distance before being canceled, sometimes down and back. By placing in the middle you're catching it. I already have an expensive rail that matches my intake manifold, so probably won't get the Radium just to have a ~6AN port. So what I will do, which you could do with your AEM is simply drill a hole directly in the middle of the rail, thread, and screw in the Radium between 2 and 3 injector. Also try ditching the oem fuel dampener as could sequence to each other, or chancel each other out. Mismatched pendulums simply sitting on a table, will algin with each other.

[@GIZZMOTORSPORTS]

@@Blakelikesfood I thought about buying the @RadiumEngineering rail, fpr, the works to see if it helps. I reached out to them for tech support and no reply. So I figured why support them and gamble my money. I already had a bad experience with the ordering and shipping of the damper from one of their vendors(I ordered from the place that said they had it in stock and could ship the fastest for a fee. Paid the money and it took 3 weeks). I'd also like to swap down to a 255 pump and 42# injectors, I'm sure that would all help. Yup lots of fun when everything works and the manufacturers are on the ball.

[@cristianmatos3505]

is your FPR a true return system or a deadhead system?

[@GIZZMOTORSPORTS]

It’s a return system. Do you know if a returnless would work any better?

[@cristianmatos3505]

@@GIZZMOTORSPORTS Actually return system, with a straight pass through, so feed one side and the FPR on the out side should help it

[@GIZZMOTORSPORTS]

@@cristianmatos3505 that’s my setup, the return at the end of the fuel rail. I’ve tried very low fuel pressure, high pressure, different pumps. I’m wanting to try slightly smaller injectors, or maybe add a 3rd fuel damper.

[@cristianmatos3505]

@@GIZZMOTORSPORTS what FPR are you running?

[@GIZZMOTORSPORTS]

AEM regulator, basically same diaphragm as this Radium unit. Probably helps to dampen a bit

[@red92da]

Why did u ditch the AEM?

[@GIZZMOTORSPORTS]

The aem fuel pressure regulator diaphragm is a consumable, have to replace maybe every 2 years. I’m back using it again, and aem fuel pump, aem series 2, wideband. I’m back using lots of aem

[@red92da]

@@GIZZMOTORSPORTS I only ask because I am doing with an issue where my fuel pressure brunches on the gauge 5 psi +/- ..??

[@GIZZMOTORSPORTS]

⁠@@red92dadoes it bounce at idle or high rpm? Does it affect afr?

[@sugoi4983]

bum ba dun da doot doot