the ticking/hammering sound you hear is the piston/rod slamming back and fourth with the HPFP chamber and on the cams.. makes you wonder if that's good or is it a ticking time bomb???

So after, spending the last seven days wrestling/testing for the various codes [P0087/9, etc..] and measuring the internals of the LNF HPFP/chamber/bore/piston/rod/spring/chamber & measuring the fuel lobes [ZZP/OEM].. So IMO I've been figuring out a few ideas and I think there is a solution.. The OEM /ZZP LNF fuel lobe by design is either too "small" or too "wide"- after measuring them all and using tools to optimize a few of designs of my own in theory.. I'm not picking on ZZP at all, they have some of the best products out there - bar none.. but IMO I think as community - we all need to come up with a way better solution to a ticking time bomb..

Finding:
#1 the HPFP spring/piston -isn't fully stable to the lobe [almost like "valve/piston float"] when the piston/spring is working past 5500+ rpm range, which causes the fuel pressure low code P0087- found this happening during my test with the Tech2, i verified with another SS/TC on the lot, and you can hear the pitch/tap is different..

#2 on HPFP piston - found the piston isn't "solid" within the bore - just a tad loose but snug.. not sure if this is the case with all DI ecotec heads.. i've checked the clearance with a feeler gauge, and as per GM - it's at spec, but this leads me to believe the "looseness" is some how contributing to the HPFP failing over time.. or possibly of oil coking?? [gotta love john@powell.. ur right john!! ash plays important part in this..]

#3 the "hydrolock effect" when there is fuel in the HPFP chamber for a split pico second and the FI isn't squirting fast enough to relieve the pressure / volume in the chamber, which is causing the P0089 code - found the HPFP coil was over loaded with the volt meter and found the reading to be negative during high loads [over 6000+rpms] which is causing the coil/diaphragm to "push" and it's the opposite during low engine loads under -4000 rpms or when the gas pedal is released..

Ideas:
After researching and learning what APR has done already:
- HPFP piston bore dia needs to be bored larger to accommodate for larger/thicker piston..
- Piston needs to be longer to control the "piston float" during high engine loads past 6000-6500+ rpm's..
- Piston spring needs to be larger to provide better and smoother piston control.
- Piston rod needs to be thicker - again to provide better and smoother piston control.
- HPFP fuel chamber needs to be enlarged to provide more fuel to the injectors, i.e.: pulse, flow, etc..

As for the lobe size, one of my many theories is to increase the lobe ramp angle to allow "more control of flow" which could help in removing both the "piston float" & "hydrolock" effect.. in theory this will provide a more stable environment within the chamber and more control of the piston..

Matt@ZZP - since the rep from Bosch stated "the multi-lobe design is for race applications and ordered with the Bosch race DI kit" [That kit is in an excess of $10k per kit, this is the same kit used by the WTCC Chevy Cruze] in which Bosch will create custom fuel/spark/boost tables to utilize with the larger fuel lobes and direct injectors" - makes me wonder if you guys at ZZP coud make a multi-lobe to work in our application $$$$ - IMO - that's something zzp [matt/zoom] need to talk with Bosch directly.. yes it will cost big bucks.. but demand/rewards would be big in the end..

The rep did go into DI & Fuel lobe theory - sizes and designs.. after the class, the Bosch rep did state - there are a many track cars [WTCC/ World Rally / BTCC / ATCC] already at 400-600hp level just with a 4 lobe designed cams.. but none in the states, b/c of the cost involved for upkeep in Bosch providing tuning/tech support/supplies to US based track teams..

now, most of the sanctioning bodies [NASCAR/SCCA/GrandAm/ALMS/etc] are looking into having DI on the race track, but the cost involved is crazy.. go figure..

LNF HPFP to fail in the future?? but the proof in the HPFP & 3 Lobe design.. maybe a better engineered Cam Lobe, HPFP & DI setup - it's possible to reach past 1500hp in the near future??

 

Interesting. No knowledge on the subject but curious

 

Just wait until we start seeing more hpfp failures from the increased stress the ZZP larger cam lobe puts on the pump shaft and the fact they're running the pump with no gasket. Just saw the first pump failure after having the ZZP cams in for a few months, too much pressure on the piston caused a fuel leak into the crankcase. Fuel contaminated oil- nice. Not. Talk about a ticking time bomb, has anyone ever seen a crankcase filled with fuel blow apart?

I've said this many, many, many times before, YOU CAN HAVE THE BIGGEST HPFP IN THE WORLD AND IT WILL NOT FIX THE LNF FUELING PROBLEMS WITHOUT ALSO GETTING BIGGER INJECTORS!

I've tried to show logs on here proving that you can have plenty of high pressure fuel and still have massive injection window misfires because the injectors are just not big enough to flow anymore fuel. Messing around with the hpfp and larger cam lobe is a waste of time, and causes more problems than it attempts to fix. At this time, the absolute BEST solution to the fueling limit on the LNF's is adding secondary fuel. Instead of stressing the hpfp more, you take the load OFF the hpfp and injectors.

 

Very interesting. Any thoughts on possibly doing a stand alone unit for additional injectors and taking references off key sensors (Map, cam and crank)? I know cost would be difficult (mainly time consuming) but has anyone played with the idea yet?

 

Idk why you're experiencing a low fuel pressure code. I only experience the high pressure code with the fuel lobe. I have looked at my tune as well and it doesn't have that code disabled. I do agree that the lobe will cause the fuel pump to fail quicker though.

The biggest issue is injectors like gm tech said. If we can get someone to create new injectors or even port our stock injectors that would be the greatest achievement in adding fuel to the fuel starved lnfs.

 

Yeah you're right, he shouldn't be getting a low pressure code with the larger lobe cam anyway. I'm betting that particular issue is tune related unless the pressure IS in fact going too low. Any logs showing these fueling issues? What are the pressures set at in the tune? Is the pressure actually physically dropping? What's your low side pressure running at? Good research and info on the hpfp, but I think you're looking in the wrong direction. H#ll I don't even have the big fuel pump lobe cam and I don't run out of fuel pressure, ever. Desired and actual are always dead even in my logs, and that's at ~550/550 crank hp/tq.

 

Interesting. When you say APR do you mean GOAPR.com?

These LNF injectors are limited at about 420whp on pump. I even had this talk with Eurocode tuning in torrance about TSI injectors. The Injector upgrades for the TSI on the APR stage3+kit is OUR stock LNF injectors. With the APR Stage 3+ kit for the GTI they are maxed out at the same hp level as we are(pretty obvious cause same injectors). They have the same technology of HPFP that is chain driven so I don't think that is the issue. As gmtech stated I believe the problem is injectors.

 

I believe ZZP was working on a 4 lobe design early on, but ran into an ECU programming roadblock getting it to work. If GM is using them then they'd need to release their code for us to be able to incorporate it.

 

you sir have valid points. the injectors are one of the major hurdles the ecotec platform has to date.. i like when you get to the point!!

i'm developing a fuel pump kit.. i'll have the results soon.. asap once i get the issues fixed/resolved

it all started with low fuel pressure, then further investigating lead me to the HPFP [as per GM service info diag]..

at first, i thought it was the tune, checked it out but still couldn't find anything [trims] that would cause this.. then i replaced the two fuel filters, and the problem was still there.. checked the in-tank FP and it's working fine.. next is the regulator, ordered it yesterday, should be in this week..

yep - goapr - the vdubs [even the mazda guys] have a very similar problem.. i've read apr - modded the hpfp internals, and got more flow out of it, as for the injectors, i've read [translated] the german VW forum site, there is a company in Germany working on modified Bosch DI injectors but the post was old..

i'm with you on this, but the problem is Bosch owns the code, so for us to get any support from Bosch, there has to be a massive demand for the multi-lobe design/hi-op injectors/programming for them to offer a package like this to the public..

 

You say the HPFP is what you researched into and found was bad, but you are replacing the regulator? Are you going on a basis that the regulator is not working correctly or have you already replaced the hpfp?

 

I'm waiting on a new HPFP to get delivered so I can install it, but getting the regulator is extra. since I have almost every part of the fuel system on hand except for new fuel lines..
The 2 fuel lines are 12 days away, since they are an SPO.. Also since I want to develop a few ideas I have, and bring them to market, I figure why not..

I'm going to have extra parts/replacing if not all of the fuel system to test a few ideas I have..

 

Zzp fifth injector ftw lmao

 

Rudy- you had stated that your pump did not meet spec with the ohm meter, but that would not be consistent with a failure caused by increased lift of the pump lobe. You really need to start from the beginning and send me some scans to show where your fuel pressure is not meeting demand. As I stated before, there is a good chance that your 5th injector kit is not triggering. I noticed that right after you loaded the E85 tune and started using E85 and the 5th injector that you were immediately chasing after a fuel system issue. Lets start with the basics and troubleshoot this systematically.

John is correct that our injectors often become the limiting factor. Of course it is not that simple, though. Someone running a stock turbo and E85 does not need larger injectors. They run into a midrange fueling issue based on the simple fact that the fuel pump is not cycling quick enough to keep up. Injectors, on the other hand, can support the same amount of horsepower regardless of the rpm that you are at. Because of this, our larger fuel pump lobe quickly and easily solves the problem when you are running a stock turbo and E85. Moving on to a turbo upgrade car, the problem changes. Now, instead of reaching 24psi boost at 3000 rpm or less, you might be looking at 3500 or more rpms before reaching full boost. Of course this depends on your turbo choice. Either way, you can see that the output of the hpfp can be increased by 20% or more when reaching full boost, simply because you reached full boost much later in the rpm band. Combine this with the fact that the stock turbo can not provide more than 16-18psi boost at 7000 rpm, while the upgraded turbo can easily maintain 24psi at 7000+ rpm, and now the injectors are not able to flow enough fuel (at reasonable pressures) to support 24 psi boost and E85. Basically, it is a two part problem. Which problem is more important to solve depends on your setup. Increasing fuel pump flow solves one problem, but the other problem still exists. Putting in larger injectors would be helpful on a setup with a laggy turbo and high rpm redline. To support E85 and an EFR turbo, you need to do both, or look elsewhere. Since there are no larger injectors that are readily available, most of us have looked elsewhere, which is where the 5th injector kit came in. At this time, we are working on revisions to the 5th injector kit to make it easier to install and tune. If all goes as planned, it will be a very desireable mod and should become much more common in our market.

 

10_sec- Those regulators are adjustable, I'd bump it up a good 10psi or maybe more while you have it out. (Another trick that makes the big fuel lobe cam unnecessary.)

 

At about what power level do 93 and full E85 cease to be usable with an EFR setup (we'll say completely stock hardware with maybe just bumping up the HPFP pressure), and then about what with the cam lobe? I've been seeing all sorts of numbers being thrown out there by people, and it'd be nice to get it straight from the source.

In my case I'm targeting 400hp, and I also have the fuel lobe. I'm considering if going back to 93 would actually be a better option for me or if it would still be reasonable to run E85. It seems that at some point if you keep going up in power, more will be made with 93 due simply to E85 fueling limitations over its spark timing advantages.

 

Golfmk6 vendor RAI motorsports found another Injector system that fits TSI motors. They also found that our LNF Injectors fit their TSI motors. So if our injectors fit the TSI and they found another set of injectors (from Ford) that fits. Maybe one of you guys that have the brains might want to test it out.

This the part number from ford that they posted- AA5Z9F593D

Here is the original thread Larger Injectors? Check. - VW GTI MKVI Forum / VW Golf R Forum / VW Golf MKVI Forum / VW GTI Forum - Golfmk6.com

Another thread regarding larger injectors for the TSI - Myth-Busted: 2.0 TSI upgraded injectors mystery solved. - VW GTI MKVI Forum / VW Golf R Forum / VW Golf MKVI Forum / VW GTI Forum - Golfmk6.com

Reason I'm bringing this up is cause looks like we both have same size fitting injectors TSI/LNF but we're both limited on power. Maybe it can help getting more info from another party that is doing the same thing.

 

A completely stock fuel system can support well over 450whp with injection timing and pressure adjustments made in the ecm. In most cases, you will not make enough torque to outflow the hpfp either. E85 requires 30% more fuel to run the same lambda, but it runs at a higher lambda in power enrich and makes more power overall. You are looking at maybe 20% more fuel consumption, which would drop a 450whp fuel system down to 375. More importantly, this is usually done on K04 setups that are pushing 375-400 ft lbs which causes the midrange fuel pressure drop.

You are correct that 93 would have an advantage when you are talking about maxing a fuel system. However, you just can't make make big power on 93 due to the knock threshold. E85 is in a different league in that regard.

 

Matt, I will send over scans this weekend.. I wasn't saying the big lobe wasn't a factor on the HPFP failure.. just stating "the HPFP is the problem", and comparing the profiles for both the Big Lobe and OE lobe in regard to lobe ramp angles..

interesting, need to research more on this idea..

good catch..

side note.. it sucks to search on google.com -it only shows US-based sites/info but rarely or even nothing overseas..

i found searching on google.de, gets better info/leads on bosch injectors/pumps..

 

Yea same. I was looking at other part numbers as well. I know it's from these cars

2011 Ford Flex All Engine(s)
2011 Ford Taurus All Engine(s)
2011 Lincoln MKS All Engine(s)
2011 Lincoln MKT All Engine(s)

so yea, its just down to R&D and see who's really down to test these. I will keep updating this thread when i get more info.

 

Bosch is pretty much controlling the market on the injectors.. Almost every auto manufacturer is locked down by Bosch..

I've read the thread first page to last, funny pissing match, both guys have a point, problem is - Bosch is selling similar "injectors bodies" to every body - even to APR, with the difference being- ring landings/ spray pattern/ flow rates/ imp value/ plug connections/ etc...

After looking at the pictures real closely, I believe the APR injectors are very closely similar if not the same as the LNF, the difference is the "injectors bodies" and the APR price tag: $250+ ea compared to GM's $120 ea... but I wonder if they flow 30% more as claimed?

APR got pissy b/c they realized someone found a similar injector and they may lose customers & sales over it.. that's the beauty of capitalism..

 

Check out Unitronic.. They make injectors that flow 30% more than stock for the mk6 GTI's..

 

That first thread read funny. It sounds like the Ford options aren't any better than the lnf injectors.

 

I believe they are still testing that out. The closest to be finished with the new injectors for the TSI platform is RAI motorsports with their ford ecoboost injector set up.

 

Yep exactly. I mean we should do what Arin@apr stated. Call up bosch themselves and see if they have a similar injector that can flow more with the same injector angle/spray pattern etc. They can probably make a set or something if they don't already have one for the 100000 other applications they manufacture.

 

It's possible they may have a set for us, but I would expect it would be a little costly.. since they have a "performance set for track use" again $$$$..

On the other hand I would love to call Bosch, but to put in an order for 4 injectors - I might get a simple no, but to get a very large group buy of over 40-50 sets, maybe we can get them to work this us..