Thank you sir. A day at a time, sometimes half a day. I appreciate you.
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Ditto. When a billet vacuum plate is included then I’ll consider buying a POD. It’s too risky without it, no matter how much better the POD is over the HELIX unit.
Figured I’d just post to conclude my last series of post’s. With the POD back together after the little nose piece fell off (I missed it when installed the first time) it in fact does work perfectly fine with the spool billet vacuum plate. I just put it all back together this morning and have driven probably about 40 miles and all seems okay now. Will update if any other problems arise but i don’t think they will.
I am keen to understand what causes it to fail. Cracking it seems like there is some sort of thermal expansion tolerance not being accounted for?
As the POD heats up /cools down perhaps it causes a fatigue. There is substancial additional metal material in a POD or a Helix so more material is undergoing thermal expansion and therefore needs more space taken into account? You can probably take some temp measurements of the different part metals in contact as the car warms up using a simple temp gun. To check any expansion rate differences of note. Then get a operating temp for the POD.
Whatever that is , would then allow you to either get calipers to measure either on car or set an oven up to measure before and after heating length etc.
Having a brace might not improve/solve that or perhaps it masks it somewhat?
Would a lower torque applied to the bolts being tightened reduce this or a thin phenolic gasket also?
Is there a torque reccomendation for the bolts that accounts for this?
Its The same reason why the helix breaks vacuum plates, to much new harmonics and a combo of extra weight and stress introduced into the weak cast vacuum plate over time they will break and shatter some faster than others.
I am not sure its harmonics at all I am thinking expansion/bolt torque might be the issue?
A couple of reasons I am thinking it might be but, smarter people may know better.
The billet plates were first to be introduced and there were failures, then brace was introduced with the helix and again there were still failures. Harmonics on all the devices would be essentially the same ,if not identical. So too would be the damping. So you would reasonably expect all the units to fail, if this is the real culprit.
There is one last thing that makes me suspicious, the instructions for the Helix say simply "do the bolts up 'tight'". Havent seen instructions for POD , is it the same? Does BMW specify a torque for the factory HPFP bolts? (Someone go look it up)
Now tight quite literally means , the pool of people installing these are going to be running all sorts of torque , maybe totally uneven torque on each of the 3 bolts? Now even if this isnt "the cause" I would say having too much ,too little or definately uneven torque is going to be adding to dramas. Let alone if the fastening design hasnt considered material thermal expansion things.
If some simple measurements of thermal expansion changed might make a way forward with simple tollerence changes or a phenolic gasket to help. And a basic agreed torque for the bolts.
There are different materials added with the POD/Helix and these are squished between the steel bolt head and the alloy vacume plate the bolts are threaded into. The metal parts of the pod/helix will want to expand and shink inside that squish space and in doing so will put pressure against the two ends. The weaker of which is the vacume plate, although being alloy its more flexible and expands lots more than steel bits. So when there is nowhere to go , its going to micro stress the alloy vacume plate through heat cycles , which 'might' eventually crack it. Not a fun time if you didnt torque the bolts evenly on top of that too.
PFS might like to jump in to tell me I am crazy ,or if I have hit on the eureka around torque settings etc you can always send me a POD as a thankyou
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These can crack too. So we may be holding our breath till then. Sure if you crack a plate , its worth doing the upgrade while in there.
All of this you’ve said makes complete sense and I would love to hear what PFS has to say about this.I am not sure its harmonics at all I am thinking expansion/bolt torque might be the issue?
A couple of reasons I am thinking it might be but, smarter people may know better.
The billet plates were first to be introduced and there were failures, then brace was introduced with the helix and again there were still failures. Harmonics on all the devices would be essentially the same ,if not identical. So too would be the damping. So you would reasonably expect all the units to fail, if this is the real culprit.
There is one last thing that makes me suspicious, the instructions for the Helix say simply "do the bolts up 'tight'". Havent seen instructions for POD , is it the same? Does BMW specify a torque for the factory HPFP bolts? (Someone go look it up)
Now tight quite literally means , the pool of people installing these are going to be running all sorts of torque , maybe totally uneven torque on each of the 3 bolts? Now even if this isnt "the cause" I would say having too much ,too little or definately uneven torque is going to be adding to dramas. Let alone if the fastening design hasnt considered material thermal expansion things.
If some simple measurements of thermal expansion changed might make a way forward with simple tollerence changes or a phenolic gasket to help. And a basic agreed torque for the bolts.
There are different materials added with the POD/Helix and these are squished between the steel bolt head and the alloy vacume plate the bolts are threaded into. The metal parts of the pod/helix will want to expand and shink inside that squish space and in doing so will put pressure against the two ends. The weaker of which is the vacume plate, although being alloy its more flexible and expands lots more than steel bits. So when there is nowhere to go , its going to micro stress the alloy vacume plate through heat cycles , which 'might' eventually crack it. Not a fun time if you didnt torque the bolts evenly on top of that too.
PFS might like to jump in to tell me I am crazy ,or if I have hit on the eureka around torque settings etc you can always send me a POD as a thankyou
I went with PFS because they offered a more “complete” upgrade package. Upgraded fuel rail, fuel lines, and brace from the get go….l figured they had to have learned from the mistakes spool made with their overdrive units. They say they’ve never looked at the helix units, so maybe that’s not the case.
The first thing I noticed that was different between installing the two, was how they bolt in. The helix unit uses long bolts that mount the helix and the hpfp together. The pfs pod uses shorter 25mm and 30mm bolts. (3) 25mm bolts the pod up to the stock location and then (2) 30mm and (1) 25mm bolt mates the hpfp to the pod. In my mind this would balance things out and distribute the load better than just using extra long bolts.
They’ve seemed to have done a lot of testing, so I believe in the product. I just want to know if getting a billet vacuum plate cover is something we should do just in case.
The Helix can cause one of the oil pump bolts to back out, i'm assuming do to vibrations. Also, if I remember correctly when bolting up the helix and hpfp, for one of the bolts, you needed to use an Allen key do to lack of space which would making proper torque difficult. I also believe that after spool release the billet vacuum plate the next issue was the actual vacuum pump cracking, not the plate itself, which was "solved" by the bracket later on.I am not sure its harmonics at all I am thinking expansion/bolt torque might be the issue?
A couple of reasons I am thinking it might be but, smarter people may know better.
The billet plates were first to be introduced and there were failures, then brace was introduced with the helix and again there were still failures. Harmonics on all the devices would be essentially the same ,if not identical. So too would be the damping. So you would reasonably expect all the units to fail, if this is the real culprit.
There is one last thing that makes me suspicious, the instructions for the Helix say simply "do the bolts up 'tight'". Havent seen instructions for POD , is it the same? Does BMW specify a torque for the factory HPFP bolts? (Someone go look it up)
Now tight quite literally means , the pool of people installing these are going to be running all sorts of torque , maybe totally uneven torque on each of the 3 bolts? Now even if this isnt "the cause" I would say having too much ,too little or definately uneven torque is going to be adding to dramas. Let alone if the fastening design hasnt considered material thermal expansion things.
If some simple measurements of thermal expansion changed might make a way forward with simple tollerence changes or a phenolic gasket to help. And a basic agreed torque for the bolts.
There are different materials added with the POD/Helix and these are squished between the steel bolt head and the alloy vacume plate the bolts are threaded into. The metal parts of the pod/helix will want to expand and shink inside that squish space and in doing so will put pressure against the two ends. The weaker of which is the vacume plate, although being alloy its more flexible and expands lots more than steel bits. So when there is nowhere to go , its going to micro stress the alloy vacume plate through heat cycles , which 'might' eventually crack it. Not a fun time if you didnt torque the bolts evenly on top of that too.
PFS might like to jump in to tell me I am crazy ,or if I have hit on the eureka around torque settings etc you can always send me a POD as a thankyou
We did significant vibe testing, and designed the POD to be smooth running, the big difference being the helical cut gears -it's quiet and balanced. My main concern would be if the brace wasn't put on nice and tight, on the other hand the one cracked issue did have 174k miles on it -would be premature to assume much of anything about it at this juncture. We'll keep an eye on it but this doesn't invalidate previous testing -if we see more of an issue of course we'll address but at this point there is no reason to be concerned.
Is there an interest in installing the POD if you don't have E85?
I only have sp95 eur
in my case which lphp do you recommend, 450 or 530?
I only have sp95 eur
in my case which lphp do you recommend, 450 or 530?
Probably not, unless you're out of fuel. Honestly if it were me I'd stick stock HPFP config and invest in a water/meth kit. Pump gas only usually a Walbro 274 is sufficient. You can step up to the 295 if so inclined but it would be 100% overkill and a little harder to run on stock EKP.
Chris
Chris
Thank you for your answer. I should perhaps have started by explaining the parts that I am going to install. at the moment i'm just in stg2 + mhd and xhp stg3. I will soon activate my WMI AEM 30-3350 kit. I had disconnected it because I had a problem with my injectors and my coils. at the end of the year I will replace my twins ... maybe HYDRA HP650. my tuner will be ken from wedge perf. today I don't know if my future set-up will run out of fuel. if this is the case, I have to prepare myself (technically and financially ...) ... now that you know a little more about my project, is POD still useless for me?
Finally jumped on the dyno. This was all direct injection at 95* ambient temps. PFS POD and PFS doubleshot LPFPs. Fuel was E50. 26psi on Speedtech 6266 kit.
