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What's the biggest tank I can drop into 03 vic Trunk?

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  • What's the biggest tank I can drop into 03 vic Trunk?

    Sadly the 5 tanks of my extended range 03 crown vic police interceptor will expire 04/18. I love this ride and want to keep it. It only has about 100k miles on it and I have babied it. The car is in excellent condition. It's been all but impossible to find the same tanks as stock and swap out. Especially the two tanks under the car.

    I think removing the 5 tanks and replacing with a single tank that would give me about 15 gge would be most economical option. 21x45 tank might fit. What's the biggest size tank anyone has ever been able to put In the trunk? Can I put in a 21x45 tank in there? Is 19x45 more realistic or possible even? My dream would be the 21x45, but space will be real tight, if at all possible. Anybody do this? Can a pro or an owner chime in please?

  • #2
    Working on a replacement for two of my 03 Crown Vics, and an 04. Finishing off a bunch of F150 three cylinder upfits to 2030.
    I'll keep you in mind when I work out the details. Drop me a PM so I won't have to dig for your contact info.
    Your Friendly Nazi Squirrel Administrator


    • #3
      Made some templates and they seem to fit. I'm going for the 21x45 type 4 iljin tank. Should be here next week. Most likely lose my spare tire though. Even crawled into the trunk and shut it to see if everything closed right.
      Attached Files


      • #4
        OP- I've read about the lower fast fill capacity on one big tank vs several small tanks. Makes sense if you think a given amount of heat is input but allowed to dissipate over the larger surface of many smaller tanks like the stock configuration. Just something to think about for your proposed plan


        • #5
          Well project is done. Dropped in a 21x45 tank with 15.5 gge capacity. Considering 75-80% fill I should get about 12 gge at fill up, about same as extended set up capacity. Shed 300 lbs in weight in the process as this tank plus brackets weigh 200lbs vs the 500 lbs original set up. So should get better mpg. Best of all tank expires late 2033. Btw surprising how unhelpful this forum was. It's all but dead.
          Attached Files
          Last edited by Thatitguy; 11-27-2017, 10:54 AM.


          • #6
            That is very impressive and a great modeling technique. I don't think the forum is dead and your effort will help a lot of us.. I have a very clean 2000 crown Vic that was updated to 3600 psi but my tanks are expiring this year.


            • #7
              So far getting comparable results to the original set up. Was able to get 12.5 gge fill in the new 21x45 type 4 tank. That's just a bit over what I could get in the original 5 tank extended set up. Gas mileage has improved about 1-2 mpg with the 300 lbs weight drop (Yes, I actually weighed the 5 tanks and brackets before disposal. 500 lbs total) No final word on range yet other than I've been too scared to go past 200 miles on the last 3 fill ups.
              Last edited by Thatitguy; 11-27-2017, 11:02 AM.


              • #8
                New set up is still working perfectly. Getting about 210 miles in range on a fast fill at pg&e. After all that work though, I had to bite the bullet and get a new car to stay in the carpool lane next year. Not sure what I'll do with this one of a kind sweet crown vic now.


                • #9
                  If thinking of selling, these are Crown Victoria used sale prices for last three years GovDeals PublicSurplus eBay:

                  (column 1 is years remaining on tank at date of sale; dates as YYMMDD)
                  9 2010 161008 $ 910 200K IL 2FABP7AV8AX143522 Ford CV CNG$800 GAS $1200 ex Taxi cabs
                  4 2005 161005 $3699 80K CT 2FAHP71W85X111940 Ford CV
                  0 2004 181011 $3495 178K CA 2FDHP719X4X152212 Ford CV
                  0 2004 181020 $1600 100K CA 2FDHP71934X152178 Ford CV
                  3 2004 160626 $3951 118K CA 2FDHP71994X152170 Ford CV
                  1 2003 180212 $ 750 115K RI 2FDHP71923X181041 Ford CV
                  0 2003 171231 $1500 94K WI 2FDFP71903X189677 Ford CV mis-fire
                  1 2003 170907 $1800 174K FL 2FAFP71W53X200806 Ford CV
                  1 2003 170531 $1936 49K CA 2FDFP73943X215033 Ford CV back doors don’t open new bat
                  1 2003 170501 $2993 59K CA 2FDFP73923X215032 Ford CV
                  0 2003 170217 $1402 85K CA 2FDHP71993X185488 Ford CV
                  0 2003 161110 $4405 11K WA 2FDFP71943X211485 Ford CV
                  2 2003 160818 $1200 54K RI 2FDHP71923X201739 Ford CV tank exp 2/18
                  2 2003 160626 $2800 81K CA 2FDFP71953X219112 Ford CV
                  2 2003 160418 $1075 51K IL 2FDFP71993X189676 Ford CV bad injector
                  2 2003 160411 $ 962 27K IL 2FDFP71973X189675 Ford CV not running
                  2 2003 160124 $2000 118K FL 2FAFP71W63X101668 Ford CV
                  0 2002 170618 $2550 17K GA 2FDFP729X2X136093 Ford CV
                  0 2002 170227 $1347 41K RI 2FDFP71922X131777 Ford CV
                  1 2002 161113 $ 630 258K CA 2FDFP72972X160450 Ford CV
                  0 2001 181014 $ 305 140K CA 2FAFP71951X188972 Ford CV no bat; noisy lifters; cracked windshield
                  0 2001 171009 $2863 18K MO 2FAFP72901X191079 Ford CV hail damage
                  0 2001 170811 $2650 132K IL 2FAFP71911X200809 Ford CV new fuel rail sensor 13gge
                  0 2001 161215 $1825 24K WA 2FAFP71991X188960 Ford CV
                  0 2001 161117 $2650 35K WA 2FAFP71911X181212 Ford CV
                  0 2001 160625 $3450 55K TN 2FAFP73W11X203955 Ford CV
                  0 2001 160214 $4400 56K PA 2FAFP73WX1X195564 Ford CV
                  0 2000 170718 $ 910 229K FL 2FAFP71W5YX179883 Ford CV
                  0 2000 170122 $ 611 197K AZ 2FAFP7491YX207359 Ford CV not running
                  0 2000 160424 $ 650 236K TX 2FAFP7491YX193673 Ford CV 3000psi
                  0 1999 181030 $ 285 98K CA 2FAFP7199XX115760 Ford CV no bat/alternator cracked windshield
                  0 1999 171129 $ 760 125K OH 2FAFP7195XX237483 Ford CV 3000psi extra tank 375mi range
                  0 1999 170316 $1825 132K AL 2FAFP71W9XX144407 Ford CV formerly in an accident
                  0 1998 170906 $ 500 87K OK 2FALP7296VX100017 Ford CV morgman(1)
                  0 1997 180531 $ 223 35K FL 2FALP719XVX113144 Ford CV
                  0 1997 180411 $ 276 115K TX 2FALP7290VX152033 Ford CV not running
                  0 1997 170906 $ 610 99K OK 2FALP7296VX100017 Ford CV cattana(2)
                  0 1996 171020 $ 820 68K OK _________________ Ford CV
                  0 1996 170930 $ 910 68K OK _________________ Ford CV