Fuel cell help! (Page 2 of 3)

I might be in the minority here, but I've had zero issues with my fuel cell. Literally installed it and ignored it.

Ok, we had one issue, but it was self created. I flushed the cell out with water after our first race using it to try and save the foam from the ethanol. Didn't think what that would do to the pump, and seized the pump when it rusted from the water sitting in it. Stupid, but my fault.

However, I spent hours and hours researching before I bought mine. Before it was even at my door I knew what my install would look like, where the pump was going, how the lines would be run, how the vent would be setup, everything. So when It showed up on my doorstep it was just a matter of executing the plan.

FYI, if you search, you can find an FIA ATL cell for the same price as that ebay one. That's what we did. Brand new 22gallon ATL cell for under $900. From there we bought a pickup setup from liquid Iron Industries that utilized the walbro pucks, a universal Walbro inline pump, some AN line and fittings, and a bunch of steel square tube. Had the whole install done for under $1500, with an FIA certified cell. Of course this assumes you're not counting the probably 20+ hours of my time to install as part of the cost.

No sump in my car. Just using the 4 puck pickup in the cell and an inline walbro pump. (see my post on page 1 for a cheaper alternative to the walbro). With this setup I have run to within 2 gallons of empty, and suspect I could run lower. We've never hit fuel starve. The daytona used ~5gallons/hour so we just ran based on that. Usually meant we could do up to 3.5 hour stints and only have to stop once a day.

External pumps aren't frowned on, however external surge tanks are. If you go external pump just remember to locate it at or below the bottom level of the fuel cell. I believe internal pumps may be a hair more reliable as they are cooled by the fuel, but the externals last just fine.

My guess would be that most race fuels were ethanol free.  But now that NASCAR has gone "green", you may see it happen.

It may be difficult to come up with a suitable material to handle both.  It seems the o-ring manufacturers are having this issue.

I'm going to echo everything the LemonAid guys said above. Don't bother with the fuel cell until the thing that is limiting your desired outcome is the length of your stints. If your drivers aren't within spitting distance of the best avg lap times for cars similar to yours, longer stints won't matter. If you aren't doing hella efficient pit stops already, the fuel cell won't make a difference and you're throwing your money down a hole.

Ok, so assuming that you guys are at or near perfection after your inaugural race, then I guess you should think about a fuel cell. My advice is please do not think of this as the place to shave a nickel on your build. I understand the need to be economical as much as anybody else, but saving a dime on a fuel cell build is the single worst place to do it on your Lemons car as a failure in this one system may lead directly to severe pain, lifetime disfigurement and/or death. Most of the guys on this forum know me to be a pretty fun-loving guy in my forum posts (I hope), but I'm quite serious about this. I don't mean to be a downer, but we all need to make certain that a "good enough for government work" slash "what could go wrong here" attitude doesn't creep into our fuel system designs and/or builds.

There was a car at the WRL race at COTA last weekend that suffered a fuel line failure 20 minutes into the first day. Nobody has said what caused it, although the driver seems to think he hit something that fractured a fuel line. The driver survived but will be at Brooke Army Base hospital for treatment of second- and third-degree burns for the next several weeks. Anybody who has seen what happens with burns knows this is not stuff to fool around with. I pray that the driver has a strong recovery but his life will never be the same, unfortunately.

I'm not saying that team skimped on any portion of their setup. I have no idea what the real failure was there. I'm just saying that their experience is a strong example of the deeply negative consequences of getting this part of the build not 100% right. I'm not saying you shouldn't hunt for a good deal, but "economical" shouldn't be the ultimate goal with a fuel cell installation, IMHO.

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All that said, here's how I built mine. We were at the point where fuel fill rate was the bottleneck on our pit stops, and we were needing longer stints to compete in class. On the pressure side of things, I used all stainless-braided hose. I first tried to build the lines myself, but I kept stripping aluminum fittings while building the hoses, so I relented and had custom hoses made by Pegasus, but you can get them at a lot of places. I made them myself on our second fuel cell build using Aeroquip stainless fittings and didn't strip those, and they don't leak either. Due to the ethanol in our gas now, I recommend using PTFE-lined fuel hoses, the rubber ones will degrade pretty quickly in the presence of the alcohol and you'll see the black residue in the cell. I used stainless-braid hose on the pressure side even though it wasn't going through the passenger cabin on the MR2 for an extra measure of safety against puncture or pinching. I figure on the fuel cell stuff, you really want as big a safety margin as possible. If your lines will penetrate the cabin space, you are required to run either stainless-braided hose or have it encased in conduit/pipe or metal plate. Full stainless PTFE-lined hoses are not cheap by any means, but at least for me, they buy a lot of peace of mind. Don't use teflon tape on any AN threaded fitting (but you can and will want to use it on the pipe-threaded parts on any adapters). Have a look at the technical manuals for AN fittings, you'll see that you don't have to crank them down as much as you think (or at least I didn't have to crank them down as much as I thought) due to the way the fitting is designed. XRP's fitting manual (available as a .pdf online) has a handy reference section at the back of the manual that indicates how much torque should be used on AN fittings by size, and more valuable, a rule-of-thumb reference for how much to crank them down when you can't put a torque wrench on them (which is almost always on fuel hose fittings).

Return lines (if you're running a return fuel side, some newer FI systems are returnless) ideally should be identical to the output side. You can get away with non-stainless here (unless it's in the cabin) but I'm not sure it's worth the minimal savings versus any increased risk. All my fuel-handling lines are full stainless-braid now.

On the vent, you want the vent line to run up vertically for a bit, then make several loops, run horizontal for a bit (or, ideally, uphill), and then descend to a level below the bottom of the fuel cell so that fuel can't siphon out if you get upside down. An old-school racer taught me that you want a filter in that vent system somewhere -- it can even be a little K&N bolt-on filter at the end of the line -- because air will be sucked into the fuel cell to make up for the fuel that is consumed and you don't want dust/debris getting sucked into your fuel cell that will clog the pickup/fuel filter/fuel pump. Speaking of which, it's probably a good idea to put a relatively large-media pre-filter between the feed line from your cell and your external fuel pump (if you run an external pump).

With regard to fuel pickups, we tried some variety of all of them over the years before settling on a Hydramat. They are expensive and kind of a pain to set up, but if you are putting a cell in to get maximum stint times, then you want to get every drop out of the cell. We had poor luck with getting a trap-door in-cell sump to work very well. I know that others have had good luck with a 4x4 style multiple-puck pickup setup, but I know others who haven't made that work. The only thing that I've heard work pretty much without fail 100% of the time is the Hydramat, but you're going to pony up for that one. We did and it works, but you'd better know your burn rate. We have a Hardin Marine 3-wire level sender installed and it's helpful, but fuel burn calculation is a tricky thing in endurance racing and really varies from driver to driver and is complicated by double-yellow flags, traffic, etc. There is a lot of YMMV in that part of racing for us.

Once you have your fuel cell build completed and the fuel cell is caged and bolted to your steed, give it a good test in the driveway with he car up on jack stands. At least for testing purposes, wire your fuel pump so it stays on even when the ignition is off. I find it's easier to test fuel systems without the car running so that the only noise is the fuel pump whine, that way you can both hear leaks as well as see them. Fuel is so thin that it will typically reveal its leaking condition very quickly. This is a system you do not want to be troubleshooting the morning of tech, you want it locked down weeks in advance so if you need to get extra/spare/replacement parts, you can do so without the additional stress of a hard deadline. We've had poor luck in finding AN fittings or adapters in the small-town auto parts stores that seem to be common near racetracks.

On that note, we decided to go with the fuel pump that 5.0 liter Mustangs use on our most recent build. It's a Walbro 255 pump but the output fittings are the same as on a Mustang (and a ton of other Ford fuel pumps) on the theory that if our fuel pump and the backup in our spares bin both crap out, the local NAPA/CarQuest/chain auto parts store will probably have a Ford-compatible  fuel pump in stock and on the shelf. They will most decidedly not have a "Walbro 255" or Bosch 044 on the shelf, in my painful experience.

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Ok, I hope that's helpful. Really, I don't mean to be a downer -- I just get the willies when I hear "economical" in the same sentence as "fuel cell installation." I always say (and mean) that I can always build a new car, but I can't build new drivers and I don't want to be at one of my friends' funerals (or hospital rooms) knowing that I could have done more/better to make the car safer. That theory has served me well through several crashes thus far in my Lemons career. Cheers & good luck and please ask all the questions that come to mind, this community always steps up to help out other teams.

I guess the question needs to come back up.

Are you making similar consistent times as the leader?

I checked the Barber results:

LemonAde Racing running a 3.0L inline 6 in a metro. had a Fastest time of 1:50.618 397 Laps

#850 CRX of Death wth a little 4 cylinder CRX HF had a fastest time of 1:57.011 314 Laps

I wish Roland would include a CSV version of the timecards so some spreadsheet magic could be done. Cause I don't feel like sitting there and entering 700 laps to get averages.

That being said, with a bigger engine LeMonAde is just a faster car.

Do you think the CRX can get fast enough that 14 extra gallons over the 10 you have now will make the difference between 1st and 33 do you feel that capacity is the only thing causing an 83 lap deficit?

There really are better stuff your team and its resources could be focusing on before worrying about fuel capacity.

Did you just hand type it all in or do you have a better source for data?

I like data, but not so much the data entry.

5.    The "stuff" you are probably referring to would be thing like better driving #1.  We all know driving skills come from countless hours on track and lots of coaching that costs a ton of money.  Also better car set up would help but we are currently working with what we know, which isnt much lol.  Driver changes could be faster  thats for sure and we are practicing that.

6.    So the way we see it all the fastest teams out there had fuel cells and spent way more time on track than we did.  We were only able to run an hour and a half before we had to come in for fuel using seven gallons before we thought it was dangerous to stay out in fear of running lean.  All of our drivers were more than capable to run for more than the hour and a half.  Lets say each driver can go two hours with a 24 gallon tank in the car, thats possibly three drivers before having to refuel the car.  From what i gathered at all the races ive been to its about half the time in the pits only having to swap drivers.  So if we hot pit and have all that capacity im sure we will end up somewhere much higher than 33rd place. 

Again i really appreciate all the advice for all you lemonites with so much more experience than Ill have for years.

Who is Alex? 

We are LemonAid Racing.  No affiliation with Alex Lemonade Stand. 

We have won a race with a fuel cell and won one with a stock tank.  Two different cars.  Funny thing, the Metro is only about 1-2 secs faster per lap than our E30 with the 2.7 ETA.  The Metro won and needed the fuel cell to win.  The E30 won at Road America without a cell.

Go figure.

90% of it is luck anyway.

No worries.  I didn't want any other charities disgraced with our group of misfits. 

You don't need a fuel cell to be in the top 10.  You don't even need a really fast car.  The diesel Golf in my sig was up to 6th place at NJMP Sunday morning in the spring 2014 race.  I don't remember lap times but we weren't even in the top 10.  All we did was stay on track - most of that was no trips to the penalty box and no mechanical issues.  Sunday we spent enough time in the penalty box to almost get our car tossed on the trailer.  IIRC we finished in the high 20's to low 30's.  Yes, the car is a diesel but it will still suck down 5-7 gallons of diesel per hour at race pace; way less under yellow flag conditions of course.

In our experience once the car is reliable the drivers make the most difference.  In the right hands our car is a top 10 piece all day long:  in our hands...not so much.  But is sure is fun to drive!