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850 HP on a Single Viper Fuel Pump - Installation Outline

Discussion in 'RT/10 and GTS Discussions' started by Jack B, Apr 30, 2013.

  1. Jack B

    Jack B Enthusiast

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    There have been multiple threads that have discussed the replacement of the OEM Viper in-the-bottle fuel pump with either an external or a double and triple pump in the tank with custom hangers. I took another route and installed a Gen 3 pump into a 1997 Gen 2 . The pump was installed into the 1997 OEM bottle. I took some notes and pictures during the install, the following are some observations. Let me preface this by saying I am by no means a fuel pump expert, what follows are my observations and some easily substantiated calculations.

    Some may be surprised, however, if you add a Boost-A-Pump (BAP) to a 255 liter/hr pump you can maintain approximately 850 hp.

    If anyone wants to add to or correct this post please feel free. This write-up assumes the Gen 2 has a 190 LPH pump and the Gen 3 has a 255 LPH pump.


    1. THE OEM FUEL SYSTEM
    The viper OEM fuel set-up is a two stage pump in a bottle that sits inside the tank. The bottle acts as a reservoir and keeps the fuel supplied to the engine during acceleration when fuel is low in the tank. Several high power cars have the same set-up, Mustangs and Camaro’s are some examples..

    The pick-up tube that extends out of the pump and fits into the bottom of the bottle pulls fuel from the bottom of the tank and fills the bottle, There is a pick-up orifice closer to the pump body that supplies the engine. There is a donut/washer on the inside bottom of the bottle that the pump sits on, that washer keeps the fuel trapped in the bottle. Under normal operating conditions the bottle is always full, therefore, acting as a reservoir that keeps the fuel flowing during hard straight-ahead acceleration or hard cornering, especially when the tank is less than ½ full.

    The tank is approximately 10"H x 29"W x 18"D. It is almost a true rectangle, with a dog bone shape to the rear and a bubble on the front. The bottle sits close to the center of the tank. The bottle pick-up sits directly on the bottom of the tank. When my gauge says ½ full, the fuel is 4" above the bottom. From the dimensions and the bottle location it is easy to see how the fuel pick-up can go dry during acceleration or cornering if the bottle did not act as a reservoir.




    Gen 2-3 Pump Compare.jpg



    2. THE Gen 2 VIPER FUEL PUMP HAS LIMITATIONS

    If you look at the following table, the 190 LPH pump is not capable of much more than 500 NA rwhp, a key exception would be a nitrous car. Higher hp NA applications might also work, but, at reduced fuel pressure, therefore, requiring some tricky a/f tuning. If you remove my 10% safety margin from the table the 190 LPH pump might give you 525 rwhp for a NA car. If a little tuning you might go a bit higher. A nitrous car could probably exceed 600 hp. The point is the hp is limited by the 190 LPH fuel pump. All these are border line and you are walking the edge. When I ran a single stage nitrous at 625 hp I could not hit my target a/f of 11.5, the car just ran out of fuel pump.

    Please keep in mind this table is theoretical, however, the basis is manufacturer’s data, the variable is the car fuel system set-up. Use the table as a starting point, but, consult your tuner for a final solution. The input data for this table came from the Kenne Bell website and the Auto Performance Engineering website

    [TABLE]
    [TR]
    [TD="class: xl70"]190L Pump (Gen 2)[/TD]
    [TD="class: xl70"]L/hr[/TD]
    [TD="class: xl70"]Gal/hr[/TD]
    [TD="class: xl70"]lbs/hr[/TD]
    [TD="class: xl71, width: 78"]lbs/hr w/Safety Margin -10%[/TD]
    [TD="class: xl74, width: 98"]Max NA Flywheel HP (BSFC = .45)[/TD]
    [TD="class: xl74, width: 64"]Max NA RWHP[/TD]
    [TD="class: xl76, width: 98"]Max Boosted Flywheel HP (BSFC = .60)[/TD]
    [TD="class: xl76, width: 92"]Max Boosted RWHP[/TD]
    [TD="class: xl70, width: 126"]Max Kenne Bell Boosted Recommendation[/TD]
    [/TR]
    [TR]
    [TD="class: xl64"]12V[/TD]
    [TD="class: xl65"]123[/TD]
    [TD="class: xl65"]33[/TD]
    [TD="class: xl65"]205[/TD]
    [TD="class: xl65"]185[/TD]
    [TD="class: xl75"]410[/TD]
    [TD="class: xl75"]349[/TD]
    [TD="class: xl77"]308[/TD]
    [TD="class: xl77"]261[/TD]
    [TD="class: xl64"][/TD]
    [/TR]
    [TR]
    [TD="class: xl66"]13.5V[/TD]
    [TD="class: xl67"]161[/TD]
    [TD="class: xl67"]43[/TD]
    [TD="class: xl67"]268[/TD]
    [TD="class: xl67"]242[/TD]
    [TD="class: xl67"]537[/TD]
    [TD="class: xl67"]456[/TD]
    [TD="class: xl67"]403[/TD]
    [TD="class: xl67"]342[/TD]
    [TD="class: xl64"][/TD]
    [/TR]
    [TR]
    [TD="class: xl64"]17.5[/TD]
    [TD="class: xl64"]203[/TD]
    [TD="class: xl65"]54[/TD]
    [TD="class: xl68"]338[/TD]
    [TD="class: xl65"]305[/TD]
    [TD="class: xl75"]677[/TD]
    [TD="class: xl75"]575[/TD]
    [TD="class: xl77"]508[/TD]
    [TD="class: xl77"]431[/TD]
    [TD="class: xl64"][/TD]
    [/TR]
    [TR]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD="class: xl65"][/TD]
    [TD="class: xl75"][/TD]
    [TD="class: xl75"][/TD]
    [TD="class: xl77"][/TD]
    [TD="class: xl77"][/TD]
    [TD="class: xl64"][/TD]
    [/TR]
    [TR]
    [TD="class: xl70, width: 111"]255L Pump *(Gen 3)[/TD]
    [TD="class: xl73"]L/hr[/TD]
    [TD="class: xl73"]Gal/hr[/TD]
    [TD="class: xl73"]lbs/hr[/TD]
    [TD="class: xl71, width: 78"]lbs/hr Safety Margin -10%[/TD]
    [TD="class: xl74, width: 98"]Max NA Flywheel HP[/TD]
    [TD="class: xl74, width: 64"]Max NA RWHP[/TD]
    [TD="class: xl76, width: 98"]Max Boosted Flywheel HP[/TD]
    [TD="class: xl76, width: 92"]Max Boosted RWHP[/TD]
    [TD="class: xl78"][/TD]
    [/TR]
    [TR]
    [TD="class: xl64"]12V[/TD]
    [TD="class: xl64"]208[/TD]
    [TD="class: xl65"]55[/TD]
    [TD="class: xl65"]346[/TD]
    [TD="class: xl65"]312[/TD]
    [TD="class: xl75"]692[/TD]
    [TD="class: xl75"]589[/TD]
    [TD="class: xl77"]519[/TD]
    [TD="class: xl77"]441[/TD]
    [TD="class: xl64"][/TD]
    [/TR]
    [TR]
    [TD="class: xl66"]13.5[/TD]
    [TD="class: xl67"]246[/TD]
    [TD="class: xl67"]65[/TD]
    [TD="class: xl67"]410[/TD]
    [TD="class: xl67"]369[/TD]
    [TD="class: xl67"]819[/TD]
    [TD="class: xl67"]696[/TD]
    [TD="class: xl67"]614[/TD]
    [TD="class: xl67"]522[/TD]
    [TD="class: xl64"][/TD]
    [/TR]
    [TR]
    [TD="class: xl64"]17.5V[/TD]
    [TD="class: xl64"]351[/TD]
    [TD="class: xl65"]93[/TD]
    [TD="class: xl65"]584[/TD]
    [TD="class: xl65"]526[/TD]
    [TD="class: xl75"]1168[/TD]
    [TD="class: xl75"]993[/TD]
    [TD="class: xl77"]876[/TD]
    [TD="class: xl77"]745[/TD]
    [TD="class: xl64"][/TD]
    [/TR]
    [TR]
    [TD="class: xl64"]20V[/TD]
    [TD="class: xl64"]440[/TD]
    [TD="class: xl65"]116[/TD]
    [TD="class: xl65"]732[/TD]
    [TD="class: xl65"]659[/TD]
    [TD="class: xl75"]1465[/TD]
    [TD="class: xl75"]1245[/TD]
    [TD="class: xl77"]1099[/TD]
    [TD="class: xl77"]934[/TD]
    [TD="class: xl64"]750-850[/TD]
    [/TR]
    [TR]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD="class: xl63"][/TD]
    [/TR]
    [TR]
    [TD="class: xl63"]1. Based on 50 psi.[/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD="class: xl63"][/TD]
    [/TR]
    [TR]
    [TD="class: xl79, colspan: 5"]2. BSFC can vary dramatically on supercharged applications.[/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD="class: xl63"][/TD]
    [/TR]
    [TR]
    [TD="class: xl79, colspan: 6"]3. In high hp applications fuel line losses can reduce max attainable hp.[/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD="class: xl63"][/TD]
    [/TR]
    [TR]
    [TD="class: xl79"] * Assumed[/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD][/TD]
    [TD="class: xl63"][/TD]
    [/TR]
    [/TABLE]








    3. AN AFTERMARKET FUEL PUMP AND A NEW PROBLEM
    The generally accepted fix is a to install an external fuel pump or a double/triple pump set-up inside the tank. This post is not about the technical aspects of a double or triple pump install, obviously there are a lot of successful installations. However, the problem with any installation that does not use the reservoir bottle with the OEM two stage pump is that at some point (unless the tank is full) you will experience fuel starvation. It could happen in a corner or at the drag strip at the top of first gear. In many cases it will be almost indiscernible, but, if you are logging you will see a drop in fuel pressure and a dip in acceleration.

    Even if you use the factory bottle to house a two pump set-up, you will have the same starvation issue unless you are using a two stage OEM pump. If you say you haven’t encountered fuel starvation, you just haven’t driven the car hard enough or have not had the car on slicks, that applies to both drag and track tires. I went to a 255 LPH aftermarket Mustang pump and I would always experience fuel starvation at the drag strip at the top of first gear.. The only way I had to cure my problem was to keep the tank near full, that is an extra 90 lbs or an added 1/10 of sec to the ET.


    4. A GEN 3 PUMP WITH BAP:
    The Gen 3 pump appears to be a 255 LPH pump. With the addition of a Boost-A-Pump (BAP) to the Gen 3 pump you can possibly take a car approximately 850 hp. This is a very nice option for a medium high hp Gen 2 car.

    I can personally substantiate that the 255 LPH pump with a Boost-A-Pump (BAP) will take a nitrous car to 850 rwhp/1000 ft lbs. The BAP is an voltage regulator that has an adjustable set point. The BAP only increases the voltage when you are at or near WOT, the sensitivity is adjustable. The fuel pump is a simple DC motor and as you increase the voltage the pump spins faster giving you more flow.

    The previous flow table shows the output of both the 190 LPH and the 255 LPH pumps at 12V, 13,5V, 17.5V and 20V. The MSD BAP actually has a peak output of 22 volts .The input data for this table came from Kenne Bell.


    5. INSTALLING THE GEN 3 PUMP INTO A GEN 2

    A. THE PARTS
    The install is fairly straight forward. You will need the following:

    i. Gen 3 pump.

    ii. A Gen 3 in-the-bottle connector harness. This is the two wire connector and associated wires.

    iii. A 6" piece of submersible 1/4" gas hose. NAPA part #H315. You can use the old hose, however, I found mine was deteriorating.

    iv. Two hose clamps, the more compact the clamps the easier the install.

    v. The plastic Gen 3 OEM cage (not the hold-down clamp) that goes over the Gen 3 pump. This is pressed on to the pump and in turn the hold down spider in the bottle presses down on this to keep the pump in place
    .
    vi. The Gen 2 donut/gasket that goes between the bottle and the bottom of the in-the-bottle pump filter. The old donut is probably going to be reusable.

    vii. Two female socket terminals. You will use these to terminate the Gen 3 pump connector conductors to the existing Gen 2 in-the-bottle connector. Viper Specialties stocks these terminals. Personally, I would get at least four, just in case a crimp goes wrong.

    viii. You will need a crimp tool that does the double fold termination. This is a common automotive crimp.

    ix. It is not a bad idea to get connector release tool, it is a small thin screw driver looking tool.


    B. THE BOTTLE ASSEMBLY

    For information purposes there are two filters on the Gen 2. There is a filter in the bottle and also one on the outside of the bottle, directly on the bottom of the bottle. That filter actually rests on the bottom of the tank. I have a feeling there is more than one fuel filter set-up for the Gen 2, however, that should not impact this install.

    This is mostly common sense and it is fair ly simple, here some hints:

    I. The Gen 5 connector that goes into the pump has two wires that must terminate into the four position Gen 2 connector at the top of the bottle, you must remove the original Gen 2 wires and terminate the Gen 5 wires into the top connector. This is where the female terminals are needed.

    The connector cap must be removed. This is pushed outward from the back side of the connector. This exposes the release tabs on the inside front of the connector. When you snap the female terminals back in, make sure the short side of the connector goes into the locking tab - when you see them it becomes obvious what is short/long. If you get this wrong the pump will not work or it will work intermittently.

    ii. Next, snap on the plastic cage that goes over the top of the Gen 3 pump. This an OEM Gen 3 part and is NOT the Gen 2 hold-down mechanism,

    iii. Take the Gen 2 hold-down cage and remove an 1/8" all the way around the inside diameter with a dremel tool. The Gen 2 hold down clamp/spider will not fit over the Gen 3 pump unless you provide this clearance.

    iv. You have to cut an 1/8" plus from the Gen 3 pump’s bottom pick-up tube, otherwise it bottoms in the bottle and the donut will not seal.

    v. Assemble the pump set-up, that means the donut, filter, hose, connector and pump, then place it into the bottle. Put the hold down clamp/spider over the assembly and push down as far as it will go, You will find that it stands approximately 3/8" higher then the Gen 2 did. This means the internal hold-down clamp is not fully seated. Just to make sure it was held in place I put two thin flat head stainless self tapping screws into the bottle/clamp.






    Gen 2-3 Fuel Pump Connectors.jpg



    C, INSTALLING THE BOTTLE INTO THE CAR.

    Again, this is common sense, but, here are some tricks:

    i. Slide the bottle/tank gasket over the bottle and position it one inch from the top of the bottle. Coat it with a non-silicon coating like tire sheen, this makes it easier to work into the tank.

    ii, Once you have the bottle seated tight against the tank neck you must start the threaded tank hold-down cap, The trick is to mark the starter threads (top/bottom) and position it correctly or it will get cross threaded. Once you have the cap started about ½ turn you can use a 12" 1 X 2 piece of wood with a rubber mallet to gently tap the cap another ½ turn.

    If you do not start the cap in the right position, you will not be able to start the threading process.

    iii. Lastly, if the fuel line has been off for a while, you will want to squirt some gas into the line, otherwise, you will have a hard time seating the line into the bottles’s male stub, it will bind if it is dry. If you do not seat it completely you take the chance of having it come off under pressure.



    Inside Fuel Bottle.jpg






    Gen 2 Fuel Pump Bottle.jpg
     
    Last edited: Apr 30, 2013
  2. Viper Specialty

    Viper Specialty Viper Owner

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    Nice Jack! Finally someone who gets the importance of a surge system that functions, haha. I have toyed with the idea of trying to make a "combo pump" arrangement for the Gen-2 guys who are stuck in a pinch. I suspect that the late Gen-2, Gen-3 and Gen-4 pumps can be interchanged with very little modification, but the Gen-1 and early Gen-2 pumps with the canister top filling port present a problem. I may get my hands on one of each and see what can be done to make a "Frankenstein" setup that will drop in, but give the advantages of the Gen-3 and 4 pump sizes. The Gen-3 IMHO is the best "all around" design using a 255lph and a large surge reservoir making it ideal for "add-a-pump" arrangements and external pump draw, but the Gen-4 also offers some interesting options. The Gen-4 is a 400lph from what I can tell, but has the "second stage" as part of the bottle rather than the pump, therefore it can run any pump size aftermarket or OE than can physically fit. However, it does have the smallest surge capacity of all pump versions, and almost zero ability to plumb the top for extra feed/return ports... so its a trade off, but for just a bout any application short of huge-power, it is plenty. For the "huge power" guys, we are working on something else :D
     
  3. 99 R/T 10

    99 R/T 10 Enthusiast

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    for the Gen II GTS and RTs, if I understand it correctly, the fuel canisters from 1996-1999 are all the same. The 2000-2006 SRT-10s are all the same. Not sure about the 2008-2010s, but I assume they didn't change the design.
     
  4. Viper Specialty

    Viper Specialty Viper Owner

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    From what I have seen, there is a Gen-1 version, an early and late Gen-2 version, a Gen-3 version, and a Gen-4 version. All are distinctly different, though LG2 and G3 are very similar in design, albeit different pumps.

    G1 is brown with a filler on top [190lph]
    EG2 is white with a filler on top [190lph]
    LG2 is blue with no filler on top [190lph]
    G3 is white with no filler on top [255lph]
    G4 is white with no filler on top [400lph]
     
  5. GTS-R 001

    GTS-R 001 Enthusiast

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    Nice info Jack,


    Thanks for sharing, its exactly what I found for my TT systems is the stock pump with a BAP can handle 775 rwhp just fine without creating a new issue by paying around in the tank. The less you change the less that usually goes wrong.
     
  6. Jack B

    Jack B Enthusiast

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    08-10 are different than the Gen 3
     
    Last edited: Apr 30, 2013
  7. Viper98912

    Viper98912 Enthusiast

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    Awesome write up
     
  8. ViperTony

    ViperTony Enthusiast

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    Jack thanks for excellent, detailed write up! Well done!
     
  9. MoparBoyy

    MoparBoyy Enthusiast

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    Awesome info here, thanks!!
     
  10. JAY

    JAY Enthusiast

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    Thanks for sharing Jack . :)
     
  11. speedracervr4

    speedracervr4 Enthusiast

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    Great info! Thanks!
     
  12. dansauto

    dansauto Enthusiast

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    years ago in my TT gen 1, I added a walboro 255 in the stock canister with the OEM pump and "tee'd" them togather then ran a return. Wouldnt this give more volume and a gen 3 and also not have the issue of starvation since your using the OEM sump for both pumps? (I also ran a relay and seperate wire harness as to no overtax the OEM harness as it was only made for one pump. My set up worked great and was pretty cheap to do.
     
  13. Jack B

    Jack B Enthusiast

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    That would give you more flow and yield a higher hp capacity. How did you fasten the second pump and secondly, what did you use to wire through the bottle. The only negative would be the reduced bottle volume.

     
  14. dansauto

    dansauto Enthusiast

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    had a machine shop make me new al gromments for the top of the canister-just used zip ties to secure the second pump to side wall of canister, ran a seperate power/relay, ran a seperate return line off the rails- pretty easy and cheap.
     
  15. fe4snake

    fe4snake Enthusiast

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    Jack, will the stock injectors be able to keep up with the fuel demand? I thought that the Gen 2 injectors was the limiting factor when it came to higher HP. I believe that the Gen 2 injectors are around 45 lb/hr and that the stock fuel pump was more than capable to keep up with the stock injectors. I read that we would need to not only upgrade the fuel pump but the injectors too as a total system in order to get the proper benefit.
     
  16. Viper Specialty

    Viper Specialty Viper Owner

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    Nowhere close. G2 injectors are around 29lbs.


    As best I can tell;

    G1: 27
    G2: 29
    G3: 31
    G4: 36
     
  17. Jack B

    Jack B Enthusiast

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    This car has 50lb injectors. There has been a lot of discussion about the 29 lb Gen2 injectors and how far they can take you. Mine were static at approximately 525 rwhp, that is when I changed them out. Several tuners have taken the cars further, however, IMHO the a/f tuning is far too difficult beyond 500 rwhp with the stock Gen2 injectors.

     
  18. NI-KA

    NI-KA Enthusiast

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    GENERALLY, with regards to the canisters the differences appear to be where the rollover valve is and the overflow for the fill tube return routes back to. One group has these items as part of the canister/basket the others have these items as part of the fuel tank. From what I have been able to observe the later GEN 2 on up have the rollover and overflow as part of the fuel tank. In theory this should allow the GEN 4/5 fuel baskets to be dropped into an earlier model with minor alterations.

    For certain you cannot just drop in a GEN 4/5 fuel basket into a 1997 GEN 2 coupe. Jack B has documented the GEN 3 fuel pump into a 1997. A gen 4/5 fuel pump can be placed into a 1997 basket. Modification will be required. What affect it has on the two stage aspect has yet to be documented.
     
  19. Tom and Vipers

    Tom and Vipers Enthusiast

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    This should be a Sticky on Fuel Pumps.

    Some Questions / Clarifications:
    1. Gens 1-5 have an internal surge tank basket function (pump keeps basket full)
    2. Gen 1 & 2 have 2-stage pumps: one for basket, one for engin
    3. Lesser said the Gen 4/5 have the "2nd stage" in the basket meaning an after market fuel pump can be used and still have the basket filled with fuel.
    4. No mention if Gen 3 is a 2-stage pump or "2nd pump" in basket.
    5. What are the Fuse and Relay Current specs for Gen 1/2, 3, 4/5? (Can a Gen 3 be used in an early Gen 2 w/o any wire, fuse, relay upgrades?)
    6. In the original instructions should the "Gen 5" reference be "Gen 3"?
    7. Late Gen 2 and later Gen's have features in the tank ( probably a well the basket drops into ), is it possible to fab a well around the Gen 4 basket and drop in a Gen 1 or early Gen 2?
    8. What is the Rollover and Fill Tube Over Fill function which can be incorporated in basket or tank in later Gens?
     
    Last edited: Dec 31, 2019
  20. ViperJeff

    ViperJeff VCA Legacy Member - UT/AZ Staff Member

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    Sticky it is
     
  21. Dan Cragin

    Dan Cragin Enthusiast

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    Jack and Dan,
    Thanks for putting all this information together. In the past 25 years I've had to repair more botched fuel systems than I can remember.
    I think many shops just don't understand how to build a proper fuel system for the Viper. Many systems out there work, but are a compromise.
    The best fuel system is one that performs just like the factory setup.

    Bottom tank feed and non surge tank systems all have starvation issues.

    Back in the day we struggled coming up with a proper fuel system for our packages. The higher hp fuel return systems being hardest to develop and
    work correctly under all conditions.

    Years ago, fuel pump boosters were very unreliable and tended to fail over time, but today they are very reliable and most production
    fuel pumps can be regulated as high as 18 volts. On a normally aspirated engine you can meet your fuel requirements typically with just
    a BAP and bigger injectors. New BAP systems use a fuel pressure sensor to regulate voltage, some OE's are doing this now.

    Keep it simple, the factory type "dead head" system with the in tank surge tank can be easily modified as Jack indicated.

    One note, on our head, cam motors over 650hp we put "Y" into the rear of the fuel rails so both sides of the engine get good
    fuel delivery.

    A note on pump modules. The Gen 1 module is unique in the way it fills the surge tank. Also they can be difficult to find parts to rebuild.
    If anyone needs help with that, call me. I use the Gen 4/5 pump in all our Gen 3 builds, with a BAP it can handle some very high fuel demands.

    On really high hp forced induction applications a complete new return fuel system is needed. This is where a many folks get in trouble. Always
    keep the surge tank or you will need more than 1/2 tank of gas at all times, return the fuel from the regulator, not the fuels rails or you will
    get into vapor lock issues. Put the regulator as close to the tank as possible. Our simple solution which works well up to 1500 hp is to
    keep the factory pump module and set it up with a pump that only fills the basket. Into the top of the module we put a fuel pickup that
    supplies 2 external pumps, next comes the regulator, which returns back to the tank module. We make a plate on top of the module
    to accommodate the fittings for delivery and return. All the lines from the fuel pump to the fuels rails are changed, as well as the size of the
    fuel rails.

    We work with a company called RC Engineering that bench tests and qualifies our fuel systems before they go in the car. They
    can do complete fuel system testing or just pumps. For BAP assisted systems they can tell you how much power you can support
    at various voltage levels.

    Some notes on injectors. On Gen 1 engines, just adding headers requires changing to the Gen 2 injectors and a recalibration.
    Gen 2 injectors can handle up to 600hp at the motor, but the injectors are at 100% duty cycle at 5000rpm. You can get by
    with that on a street motor, but on a race motor you can overheat the injector drivers in the computer and damage it.
    We like to keep duty cycle around 80%. I like to only run as big a injector as needed. Gen 1 or 2 bottom feed injectors
    can be re sized, or there are bigger injectors available, the biggest require new connectors. Gen 3 injectors are good
    to just shy of 700hp, but we always go with the next bigger size.

    Your experience may differ, hope this helps.
     
  22. Dan Cragin

    Dan Cragin Enthusiast

    Posts:
    1,217
    Joined:
    Feb 16, 2007
    Location:
    LA, CA
    Another note on fuel injectors. The side feed Gen 1 and 2 injectors are notorious for clogging up over time. I started by sending them out for ultrasonic cleaning, new screens,
    o-rings and matching when we rebuilt an engine, but when I found the before and after cleaning flow documentation showed really poor flow, we started doing it on every car we tuned, keeping an exchange set on the shelf. You would be amazed at how well your car runs after this service.
     

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