AO

I disagree 200%! That in-tank pump is the biggest piece of crap ever sold by Porsche and built by Bosch. Now if you can GUARANTEE a pump that will last and supply enough fuel to not starve the 044 pump, I might reconsider my position. Until then, I will not waste any more time or money (or anyone else's) on that POS in-tank pump.

My 044 pump is slightly louder than the stock pump, but not much. The only time I ever heard it really whine was when the tank was almost empty... Oh and one time when I didn't have the cover installed right so it rattled against the cover - but that was super evident.

One other thought and a bit of a digression... I recall there was a period when there were some counterfeit 044 pumps being sold. Now, even wholesalers can get duped, so your normally reliable vendor could be unknowingly supplying counterfeit parts that just are not up to the task.

I used to work for a major parts supplier (TRW) and I remember we caught a company selling brakes made from our castings, but we didn't make them - so they were counterfeit. What we found out is that the casting supplier was selling our castings (and design) to some rouge Chinese company that then did the finishing machnng and assembly. Who knows if they used the same tolerances or safety protocols as we did. They may have been "functional" but I would have never put them on my car.

Just something to think about...

GregBBRD

Everyone is entitled to an opinion.

However, my view comes from reality and I'm not just sitting behind a computer, slinging out mere opinions.

I work on hundreds of 928s.

On Thursday, I had 6 GTS's in my shop, along with 6 other 928s.

I looked at my sales history and I replaced a grand total of 3 in-tank pumps, all of last year.

And the youngest of those cars is over 17 years old....

That doesn't make that pump the "biggest piece of crap ever sold by Porsche and built by Bosch", in my mind.

And I use the in-tank pump to feed every 044 pump that I install...and no one has ever said a single thing about them being noisy.

AO

It could be that your 044 pumps are genuine... Hence no whine. My guess is that the OP and you did not get the 044 pump from the same source.

By the way, it is not my opinion that the intank pump is a piece of crap. IT'S A FACT! I suggest you read this... Do not use the in-tank pump... EVER!

And just because the youngest intank pump you replaced was 17 years old doesn't mean it didn't fail years before you got your hands on it. I have personally seen 3 intank pumps fail within 2 years of installation. You would never know it from external appearances or how they sound. The only way to tell is to remove it and inspect it. The failure mode is that the rubber hose that connects the pump to the fitting splits. Not only does this make the pump ineffective but it also allows the possibility of grit and other foreign material to get into the pump... That's how my last fuel pump seized.

I would be willing to bet that if you were to inspect 3 of the in-tank pumps you have replaced in the past that are at least two years old or older, at least 2 of them will have failed as mine did in the link above. The reason is clear. Bosch/Porsche are using the wrong material for that little hose that connects the pump to the tank fitting = P.O.S.

GregBBRD

Or maybe the fuel or additives you are using attack the rubber?

While I don't "drag" vehicles back in to recheck the fuel pumps, I can tell you this....every single one of my strokers still has the in-tank pump still running. That's a quick cross-section of samples....100% running....and a bunch more than just three.

dprantl

Greg, many knowledgeable 928 owners all over the world who have replaced new in-tank pumps have had the connecting hose fail within 3 or so years of normal use. Just because a pump is running doesn't mean the hose is not cracked. Mine ran fine for years until one day the main pump sucked a piece of the dead rubber hose in and jammed it. Some theorize that the hose was molded using an outdated rubber formulation which is not compatible with the ethanol that is being added to gasoline nowadays. If the hose is replaced with a piece that is made from a more suitable material, there are no problems.

Dan
'91 928GT S/C 475hp/460lb.ft

brutus

One more thing to "update", put good hose on a new intank pump.

GregBBRD

And I have supplied that small piece of hose to several people....I've got bullet proof hose and bullet proof clamps, for this application....but I have so little problems with it that I don't change the hose on new pumps.....and I sure as hell don't run main pumps that were designed for use with "pusher" pumps to suck all by themselves.

That would be silly to do/suggest to people.

I'm betting that people who have super stiff suspension have more problems with the hose breaking....since the resulting inertial increase would "lever" the pump/strainer part of this assembly more....

AO

Sorry Greg, but without visual inspection, you cannot say with certainty that those in-tank pumps are still running in proper order. My car ran fine with the broken pump... Only found out it was broken when we pulled it.

But I think you are right that the additives in our gasoline these days is mostly reponsible for the degradation of that little hose. But I do not add anything to my gasoline. So it's not an isolated case. Do your strokers use pump gas or race fuel? I think there is less ethanol is race gas, but not 100% sure on that. Could that account for our different experience?

Also, looking at the Bosch spec sheet on the 044 pump, there is no mention that it requires a Pre-pump or some inlet pressure. So I think your statement that it is designed to have an in-tank pump is merely to support your claim that the in-tak pump is a good thing, and not based on fact. Sorry to call you on that, but the Spec sheet doesn't support your claim.

http://www.bosch-motorsport.de/en-US...6821238411.pdf

123

Are there any vehicles using the 044 pump as original equipment? If so, do they have an internal pump feeding it?

If the internal pump isn't capable of flowing as much as the 044 pump, it seems like it's basically just a restriction limiting the flow capacity of the 044 pump. That wouldn't be a problem on engines that don't make enough horsepower to need all of the 044 pump's capacity. If that's the case, I don't really see any need for the 044 pump in the fiirst place for those engines.

GregBBRD

No race fuel in my "street" strokers required. They are designed to use street 91 fuel.

I'm not sure I said that the 044 pump requires a pre-pump. If I did, it was certainly not what I intended to say. I've been running the 044 pumps, for years and years without a pre-pump. None of the Cup Cars feeds fuel to their 044 pumps....however, I'm not sure we've ever been concerned about fuel pump noise in a race car....which is what this thread is about.

I also don't think the pre-pump will hurt the 044 pump, so I always retain that pump, when adding an 044 pump into a 928. I think that this keeps the 044 pump significantly quieter.....which is what this thread is about.

I did say that the '89 and later primary fuel pumps require a pre-pump and if someone wants to "remove" the pre-pump on these cars, they should use the primary pump from an '87-'88 vehicle....unless they want a noisy pump...which, again, is what this thread is about.

AO

Found this interesting comparison on genuine Bosch 044 pumps and fake ones.

http://honda-tech.com/showthread.php?page=2&t=2710307

Spun

Nice link. Thank you .

OK. I am pretty sure mine are real at this point... at least the one from Roger I am 99% is real. I need to relook at the first one I got from Amazon to make sure, but I think it was Czech.

GregBBRD

Are you running the 044 pump through the original fuse and wiring, or did you add a power relay and a 12 volt power siource directly from the battery?

These pumps require quite a bit of current and it is feasible that your wiring is getting hot and the pump could be getting marginal current.

The other thing that you need to think about is if you really "need" all the trouble that a 044 pump brings? The stock pump will "support" a minimum of 380rwhp (through an automatic) and 425rwhp (through a five speed.)

Real horsepower.....not "dream-o-meter" horsepower.

Not many 928s are actually making that kind of power.

Spun

I do not believe that I need it for HP. When I discussed the need for a pump before, the 044 was the overwhelming recommendation with the tank delete filter. That is why I purchased them for both of my 89s. I am not running more than stock HP at best.

I did not add a power source of new relays. All off of stock. Any link for how to do this best? I will do that next.

If that does not work, I think I will go back to the original external pump... but I am still unclear if I need to add the internal pump back in or leave the filter.... These are stock and I will not be adding a SC to them. ... thoughts....

GregBBRD

You can certainly add a power relay, to better "feed" all the current that this big pump requires. I sell two "kits" for this pump. One is the "proper" fittings that one needs to hook the pump up "sanitarily" to the tank strainer or fuel pump. The other kit is a complete wiring kit (with instructions) that will allow you to add a relay. Others must also sell kits to "swap" the 044 pump into a
928, also.

Check with Roger at 928's R US or with 928 International. Both of those companies distribute my products, or might have their own installation "kits".

I think someone really gave you poor advice. Running that huge pump, for a stock application, is way more overkill than anyone should ever do. If you have an unused pump, I'd suggest that you ask the supplier if you could exchange it for a "stock" style pump that will run with the stock wiring...way easier and way less "load" on an already "strained" alternator.

As I mentioned earlier, in this thread, there's a stock 928 pump that was designed to be used without the "pre-pump". This is found in the '87 & '88 vehicles.

928 608 104 02 gets you the correct pump.