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  #106  
Old 11-17-2015, 03:05 AM
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I'll like to try this out on my car. Let me know when you have a batch going out

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  #107  
Old 12-04-2015, 02:47 AM
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If your setup is otherwise stock, before you go installing a modified spring take a look at this:

Fuel injection pump starvation with a good lift pump

If your car is "souped up" then stock values may not apply, but if the car is stock and a modified (heavier or longer) spring improves the performance, it may just be compensating for other problems.
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  #108  
Old 12-04-2015, 07:39 AM
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Quote:
Originally Posted by bostonmish View Post
If your setup is otherwise stock, before you go installing a modified spring take a look at this:

Fuel injection pump starvation with a good lift pump

If your car is "souped up" then stock values may not apply, but if the car is stock and a modified (heavier or longer) spring improves the performance, it may just be compensating for other problems.
The above is not really accurate ...

First, not a good idea to "stretch" the spring. So, please don't try this and do so at your own risk. Secondly, the spring is a wear item and like any wear item after a zillion cycles, it becomes fatigued. The spring is designed for all applicable engine applications, not just "souped" engines, so that is likewise inaccurate. Third, and last, the "mod'd" aspect solely deals with the slightly enhanced pressure it creates. In no way does it "compensate" for other issues. Rather, your other engine's components should be working properly or correctly regardless, and this is just one piece of the puzzle.
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  #109  
Old 12-04-2015, 08:27 AM
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Quote:
Originally Posted by greazzer View Post
The above is not really accurate ...

First, not a good idea to "stretch" the spring. So, please don't try this and do so at your own risk. Secondly, the spring is a wear item and like any wear item after a zillion cycles, it becomes fatigued. The spring is designed for all applicable engine applications, not just "souped" engines, so that is likewise inaccurate. Third, and last, the "mod'd" aspect solely deals with the slightly enhanced pressure it creates. In no way does it "compensate" for other issues. Rather, your other engine's components should be working properly or correctly regardless, and this is just one piece of the puzzle.
I completely agree. In fact, putting in a "performance upgrade" spring - aren't you the one trying to sell these? - into a pressure relief valve is kind of like throwing some against the wall and hoping it sticks.

Thanks for confirming my point on that.

The OEM pressure relief valve is calibrated to the range of 1.0 - 1.5 bar. What's your so called "performance upgrade" valve calibrated to?

Last edited by bostonmish; 12-04-2015 at 09:13 AM.
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  #110  
Old 12-04-2015, 09:42 AM
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You obviously have zero clue what you are talking about. The spring was not randomly selected. Rather, it was designed and went through a lot of R&D before being marketed. Those expenses was in the $1,000's of dollars by folks who are true diesel experts. Then, it was road tested for a while. THEN, it was marketed. OVER 80 of these have been sold and all 2 thumbs up as compared to your "experiment" which you discussed.

So, I guess folks can evaluate proven prior results, expensive R&D, and true diesel experts versus your one time experiment.

I guess even trolls take a stroll on these threads.
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  #111  
Old 12-04-2015, 10:42 AM
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Here's the body of a 6 year old thread, give or take, from WHunter ... I cut-and-pasted the entire post.

"Fuel injection pump starvation with good a good lift pump is becoming more common as the bypass valve spring gets weaker with age. A weak bypass spring allows too much lift pump pressure to flow back to the fuel tank = starving the injection pump for proper fuel volume. The solution is to install a new (or good used) bypass valve for your engine application.

MB# 0000747284
Diesel fuel return valve/banjo bolt, back of injection pump by engine block, at nylon return line going to fuel filter housing.
At this moment (March-12-2009), I have verified five new units remaining in north America.

Application list:

OM615. 910, 911, 912, 913, 914, 915, 916, 917, 919, 930, 932, 936, 937, 938, 939, 940, 941, 942, 943, 944, 963, 970

OM616. 911, 912, 913, 914, 915, 916, 917, 930, 932 933, 934, 936, 937, 938, 939, 940, 960, 961, 963

OM617. 910, 912, 931, 932, 933, 950, 951, 952

OM621. 912, 913, 915, 916, 918, 919, 930, 931, 932

NOTE:
You should replace the banjo bolt/valve seal rings at this time.

Two of the following
Item Number: 007603012111
Main Category: MERCEDES BENZ
Description: SEAL RING, BANJO WASHER
Weight: 0.02"

As stated over and over in this thread, this is a wear item. The spring was slightly tweaked as an improvement over the original design.
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  #112  
Old 12-05-2015, 03:44 AM
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Quote:
Originally Posted by bostonmish View Post
......If your car is "souped up" then stock values may not apply, but if the car is stock and a modified (heavier or longer) spring improves the performance, it may just be compensating for other problems.
The performance spring will not compensate a worn pre supply pump (valves/pump spring) and / or a worn hand primer pump (seals).

If one of those 2 are worn the performance can be even worse than before putting the performance spring inside.

Gruß
Volker
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  #113  
Old 12-06-2015, 02:54 AM
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Quote:
Originally Posted by greazzer View Post
You obviously have zero clue what you are talking about. The spring was not randomly selected. Rather, it was designed and went through a lot of R&D before being marketed. Those expenses was in the $1,000's of dollars by folks who are true diesel experts. Then, it was road tested for a while. THEN, it was marketed. OVER 80 of these have been sold and all 2 thumbs up as compared to your "experiment" which you discussed.

So, I guess folks can evaluate proven prior results, expensive R&D, and true diesel experts versus your one time experiment.

I guess even trolls take a stroll on these threads.

Here (attached below) is the MB FSM related to 617.xxx IP fuel pressure test values. As posted in various threads in this forum, including the “whunter” thread you referenced [Fuel injection pump starvation with a good lift pump. For those interested, my own data and conclusions are in that thread; post #82


Now, greazzer, as for your claims, based on your so called R&D and the “$1,000's of dollars by folks who are true diesel experts.” I say: show me the evidence.

The evidence should include, for each of the vehicles involved in your extensive R&D (and also for each of your 80 satisfied customers):

a) the systematic IP pressure testing, per MB FSM, with the original, unmodified pressure relief spring, first …and

b) then, the same tests with your “not randomly selected,” but “designed” spring

c) a table summarizing the post-modification fuel pressure values that were either:

a) Within factory specs …or

b) Above factory specs

d) an objective report on the operating characteristics of the modified test vehicles

e) the before and after MPG table

f) a report on whether any of the 80 modified vehicles overheated their IP as a result of your spring

Don’t forget to include how your so-called R&D accounted for whether the cars involved had a clean strainer, fuel filters, correctly set valve timing and valve clearances, properly adjusted IP timing, a properly functioning lift pump and known good injectors with balanced pop values and good spray patterns; also the compression test results of the test motors.

Wait… What’s that? Oh you don’t have those values? It was just too much trouble to gather this information during your research worth “$1,000's of dollars?” I see. Well, then, your spring, my dear greazzer, is just snake oil.

Had you done real R&D (like that done by Bosch or MB or Monark) you would have some credibility. You have not, therefore you have none. Sorry.

Perhaps you want to insist that your own unique greazzer insights are superior to those of the silly german enginners, what with their fancy-shmancy engineering degrees and those ivory tower research labs, with those white labcoat wearing scientists, looking down their noses and issuing those condescending MB FSMs with actual fuel pressure values; …that all of their research is just an unproven theory compared to your faith based spring.

It looks like, absent real data based on real R&D, that would have to be your position. In that case, my dear greazzer, YOU are the troll.

Now, about those 160 thumbs (80 customers x 2 thumbs, assuming each had 2) that you have offered. Is that your evidence? Thumbs are not evidence. Even 160 thumbs are mostly wishful thinking. Before and After fuel pressure values are data that could be evidence. OK ? Make your argument based on real facts.

So, once more I say: show me the evidence of what your modified spring does to the fuel pressure.

If it just brings the pressure to within factory spec, we come back to my main point – that the stronger (or stretched or shimmed) spring just compensates for some other fuel delivery problem. One danger is that it obscures the problem making it that much more difficult to bring the car into proper spec, but that may be of little interest to some.
Attached Thumbnails
Performance Overflow Valve-injection-pump-testing_1.jpg   Performance Overflow Valve-injection-pump-testing_2.jpg   Performance Overflow Valve-injection-pump-testing_3.jpg  
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  #114  
Old 12-06-2015, 05:17 AM
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Dear M.P., I suggest you stick to domain name buying or motor bikes, or whatever. My last time entertaining you and you can troll along. The spring replaces a repair item and enhances what the German engineers created. Whether or not you like what I did is irrelevant and the work I did (and do) is established by the folks who already purchased one.
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  #115  
Old 12-06-2015, 11:39 AM
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I will be interested in one at some point; not all of us are engineers, some of us are mechanics who experiment.
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  #116  
Old 12-07-2015, 07:22 AM
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I will be commencing sales again in a few weeks. No need to be an engineer or a scientist. It's pretty simple operation to install, and it's pretty simple to understand that wear items do wear out and to install the replacement item which slightly enhances performance is a win-win scenario. I will post shortly a new thread for 2016 since this one got cluttered with a bunch of irrelevant posts.
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  #117  
Old 01-07-2016, 07:12 PM
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I got some fresh stock in and I will be posting pictures shortly. So, if anyone is interested in NEW OFVs or just the spring, please PM me.

Last edited by vstech; 01-08-2016 at 06:54 AM.
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  #118  
Old 01-07-2016, 07:53 PM
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Here are some pictures of my remaining 2016 stock.

There are brand NEW, freshly machined OFVs with all new internals, and the mod'd spring. I have 13 of those left (one is not pictured). $41.50 shipped Priority Mail USPS with $50 worth of insurance CONUS. Turbo applications.

I have springs, I have 8 or 9 of those left. You will need a rebuildable OFV to use the spring. $35.00 shipped Priority Mail USPS with $50.00 worth of insurance CONUS. Turbo Applications.

There are brand NEW, freshly machined OFVs with all new internals, and the mod'd spring. I have 2 of those left. $41.50 shipped Priority Mail USPS with $50 worth of insurance CONUS. NON- Turbo applications.

Overseas is around $20, depending on your country -- however, overseas there is no insurance once it leaves CONUS.

PM if interested.

As with my injector service, my lift pump service, and soon HPN/SLS pumps and shocks, I stand behind my work 100%. If you really feel this did not "help" your car, simply return to me for a full refund to include your shipping back to me up to $5.75. So, you loose nothing. However, I will know if you took it apart (NEW units) or if you messed with the spring. I am now warning folks, if you messed with the NEW unit, e.g., took it apart or distorted the spring, I am not refunding your money. Period. So, leave it alone,
PM that you're returning it, and do whatever else your heart desires. So far 100% customer satisfaction and I can simply resell unmolested stock. Now, if you drive it around for months and then claim it was no help, same deal as taking it apart or messing with it ... You will know rather soon if it enhanced performance or not.

After reading "comments" from a few trolls and handling one curve ball, this is what I have to say.

1. If your car has other fueling problems, there's a chance this may exacerbate those symptoms. So look into those issues also.

2. The OFV is a wear item, and like any wear item, once it becomes degraded, the lack of PSI will impact your engine's performance.

3. Having sold 98 of the springs and two swaps, nothing but 2 thumbs up. Having sold a few of the new OFVs so far, same thing, nothing but 2 thumbs up.

4. These are shipped with insurance and tracking thru PayPal's protection plan as well as the insurance program with the USPS. If the USPS says it delivers your item, but you contact me claiming you never got it, there's nothing I can do about it. I had this happen, filed the claim, lost and then filed the appeal for the customer and lost again. I personally went to the post office and spent about 20 minutes talking to the guy in charge and he said tracked packages are really tracked. So, that's all I can do.

So, once these sell out, I will re-evaluate whether to get more stock in or not. Once these sell out, I should be at the 125 mark which is pretty decent track record. I apologize for the delay in getting this out.
Attached Thumbnails
Performance Overflow Valve-img_2462.jpg   Performance Overflow Valve-img_2463.jpg   Performance Overflow Valve-img_2464.jpg   Performance Overflow Valve-img_2465.jpg   Performance Overflow Valve-img_2466.jpg  

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  #119  
Old 01-08-2016, 01:18 PM
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As one of the very few people that continuously monitor my fuel pressure in real time, I can report that fuel pressure varies significantly. In order to get a stable reading I employ three strategies - first I have a snubber consisting of a tiny orifice in an epoxy plug in the fuel transducer capillary line, then I have a damper consisting of a piece of closed cell foam ahead of the sensor, and finally I do software averaging of a significant number of readings. When originally installed, the readings were "reasonable", but after doing the spring stretch procedure in the OFV valve the readings jumped - not quite double.

So, while I'm not using the Performance Overflow Valve, it's pretty obvious that this mod would have a profound effect on fuel pressures compared to a worn spring.

The pressures are so variable because of the lift pump being a positive displacement design - when the piston is on the "intake" stroke pressure quickly drops to near zero and when it is pumping it jumps quickly to the limit pressure of the OFV valve or possibly a bit more. What I've been wondering about recently is the notion of adding a fuel pulse damper (pressure damper or accumulator) to the system between the pump and the injector pump. If it's true that the extra pressure of the Performance Overflow Valve increases performance by increasing the fill rate of the elements, it would seem reasonable to assume that a constant design pressure would serve the same purpose and possibly reduce the stress on the lift pump.

As I'm writing this, I'm wondering whether it's possible that a check valve in my lift pump might be leaking producing the low pressures I'm seeing i.e. allowing the fuel to bleed back through the pump rather than being maintained on the pressure side.
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  #120  
Old 01-08-2016, 01:50 PM
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Quote:
Originally Posted by DenverW123 View Post
1+2=3

Funny how you describe skeptics as "trolls".
Considering the overwhelming response from folks in this very thread, skepticism seems unwarranted. But to the point, I believe he called you a troll because of your approach, not skepticism. A skeptic wouldn't claim he was charging too much, a tropical would. A skeptic Would ask for empirical evidence, which you haven't...

I think Mach 4 needs to buy one and report his findings... As for me, I have no doubt it works. I will buy one eventually.

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