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Jack Leslie's 1957 Sedan Delivery

2024 April
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Stripes

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Posts posted by Stripes

  1. The line from carb to the pump is pressurized with gasoline. If it leaks, it can spray fuel onto your starter, alternator, plug wire, etc and burn you and your car to the ground. Every car I have ever seen from the factory has metal lines from the carb to pump. If the suction line leaks to the tank, it just quits pumping fuel. So, Frosty is giving some very bad advice based on others that have done it wrong  many times. If the line never leaks, it might be ok. Even the NHRA limits the amount of rubber fuel line a car can have and race. This includes steel braided lines. This is for fire safety.

    Many car fires are caused by leaking rubber hoses. In a claim I investigated, a drunk patron returned to his truck and passed out with his foot on the accelerator while in park. The engine screamed but no one wanted to break a window of another's car. The alternator got hot enough to fail and dripped hot metal directly on the truck owners altered rubber fuel line. The resulting hole sprayed gas directly behind the reved up fan. Igniting and resulting in an inferno that killed the owner and burnt the truck to the ground.

    Those metal lines are there for a reason. The carb has a place for an internal filter. Use rubber lines in very short sections to connect metal lines together, or for emergencies. Otherwise, spend the 20 bucks to replace the line with steel.

  2. Good luck! With the vapor lock issues we had, we didn't have a choice. While we are very happy with the Sniper, had we not had carb / vapor locking issues we would still be running a carb. As they add more alcohol each year to the gas, it gets more difficult to keep from boiling fuel in the lines, especially with increased hp which generates more heat.

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  3. Wiring the Sniper was easy. The hardest part is removing all the wires you don't need, like nitrous, electric fan. Etc. You first take the car and have the exhaust bung placed in an exhaust pipe.  Wires to hook up: power, ground, temp sender, O2 sensor, fuel pump wire to pump. To tune. tell the system the engine size and desired idle and start it. If self tunes. I think driving it around it tuned itself 80% in about 30 minutes. The Xflow Sniper uses a external fuel regulator, I set at 60psi.

     

    I bought a replacement battery that was the same size but had top and side post. I hooked the main power off the provided harness to the side terminals so I could continue to use the OE spring ring battery terminals.

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  4. Sure. The picture is of the same Pontiac iron spread bore intake manifold. The Holley Sniper X-flow has duel bolt holes to allow it to bolt to either a square bore manifold or a spread bore manifold. The issue with a Pontiac factory intake manifold is as shown in the photo, the restriction would have been huge if it had not been modified.  To resolve the issue, we took a sawsall and grinder and opened up the manifold to the point that the Sniper would see no restriction. This resulted in huge power increases and no need to run any power robbing spacers.

    Sniper does make a 650cfm spread bore fuel injection unit. I felt since the original carb was 700cfm with the engine in stock form, a 650 cfm would restrict my HP. I realize they claim it supports 600hp, but we can discuss what that really means and doesn't mean at another time. On the dyno the 800 holley 4150 made 40 more hp than the factory carb. Lets talk about what works well.

    Additionally, the factory manifold was up about 20hp over the E RPM+ and the torker, from our dyno tests when the engine was assembled. Both of these aftermarket manifolds  had hood and air cleaner clearance issues, in the car, which also caused the top of the carb to sit too close to the top of the air cleaner with drop base air cleaners. The drop base air cleaners were required to allow the top to clear the hood on a 69 firebird. Additionally, the hp loss was recorded on a dyno with no air cleaners at all!  So unless you are running over 500hp, and larger than a 468 turning up to 6000 rpm, an aftermarket intake manifold is a losing proposition.  I believe an aftermarket intake with a drop base air cleaner could be over 30hp down. To be fair, I port matched all intake ports to the D port E heads prior to dyno testing, and the iron factory intake was matched to RA4 port sizes the E heads use. Heck, even the Edelbrock intake manifolds ports sizes are way small on their manifolds when matching to their OWN out of the box D port Aluminum E heads.

    Now, the engine with fuel injection appears totally stock with the air cleaner on, and the performance and drivability improvements are huge! I highly recommend the Sniper X-flow (900 CFM). Of course the best part is there is no VAPOR Lock anymore as the fuel line has 58lbs of pressure instead of a vapor lock inducing vacuum on the fuel line. Fuel pump in the tank can not be heard or seen! Wheel spin is instantaneous. Recently at a car show a bystander walked by and said, look a totally stock Pontiac 400. I found that highly complimentary since this was now a 455 bored 60, with  forged rods and pistons, a hyd roller Comp cam, RA3 exhaust manifolds, HEI, and a 900 CFM Sniper FI making over 500hp and nearly 600 ft lbs of tq.

    Here are some more photos of the manifold as we modified it.5AD6F404-2B0D-4763-9129-8AEBA36D3A20.thumb.jpeg.aef3193442251f11737f33e6794077d3.jpeg

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  5. It all depends on the clearance you have at the valves. All Pontiacs have around .420 lift and most have non adjustable valve trains except on RA2 & 4 & 455SD engines. While they will physically fit on the engine rocker stud, Pontiac did a few things to ensure their 400 RA4 engines didnt blow up with 1.6 rockers. The push rod holes typically need to be enlarged to ensure the pushrod doesn't contact the head. And adjustable rocker studs are will be necessary so you can lash the valves. The factory valve springs will bind if not replaced, and the taller springs need their location milled to accept tall springs to prevent binding.  Other than that its a go. 1.6 are hard on pushrods, many replace theirs with better ones. The best working fix is a cam with more lift ground into the cam, and then use 1.5 rockers for reliability.  1.6 rockers will add about 3 degrees of duration and around .040 " lift to a stock cam. Dropping them on a stock motor will very likely result in a broken valve springs, bent pushrods, and a walk home...

  6. The Holley X-flow 900 CFM works extremely well of a 468 Pontiac with a hyd roller cam. We made 500hp and over 550 ft lbs and have perfect cold starts, great fuel handling and better mileage than a factory carb.  We modified the stock iron intake to accept the X-flow, bolts right up with no spacer required. Factory air cleaner fits, no hood interference and much more HP than a RPM+ or Torker manifold.

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  7. We have 2 69 Fb's, one with a 4 speed muncie, one with a 700R4 overdrive with a tight 2200 stall convertor.. I love driving the Muncie equipped 4 speed, shifting the gears, selecting when I want to change the rpm level, and such. My wife hates the manual car, and loves her car with the 700R4. Her car will white smoke the tires for long ways, has crisp shifts, and at 70 mph is turning about 2000rpm. Both cars have 3.55 rear end gears. With her 700r4 she has the equivalent of a 4.20 rear end gear in 1st gear, and a 2.56 rear gear equivalent in 4th. Best of both worlds. 

    The cars have different power levels, but I suspect the 700r4 would be faster at the drag strip as it allows a continuous transmission of power, as compared to a manual that has to release and re-engage the engine at shift points, and traction issues related to hooking it up each time.

    It sounds as you need a better transmission builder for your 700r4. Properly built, they work great. Hers has been to the drag strip with drag radials and held up well. 

    With the manual, remember there are a lot of items to maintain. Clutches are designed to wear out, so expect to replace it on occasion. 

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  8. If your total budget is $2,000, a hyd roller will not be cost effective enough, although supeior in performance. A gear change/or transmission change is a must. So, realistically, your budget is main limiting factor. Rear gear, set up, gaskets, and fluid will run at least $500. 3:73 is too low for a non overdrive street driven 455 that sees 70 mph speeds for long distances. We use 3:55 with a 700R4 overdrive transmission. With no overdrive, the highest I would go is 3.08-3.23 if you do a lot of highway driving, or maybe 3.42-3.55 around town. Keep in mind, Pontiac ran 3.08 rear gears in their 455SD cars and they ran great!  

    There is no need to change your intake, your factory iron 4 barrel intake will outperform any aftermarket intake at less than 500hp.

    The lowest power to dollar hp increase that is available in the market is Nitros Oxide. A 125 hp kit, NOS Powershot Nitrous Oxide Systems is $550.  To safely run this kit, a fuel system upgrade will be in order. Expect to add an electric fuel pump, and either a larger fuel line or another fuel line, fuel pressure regulator, and filter.  You will have about $300-500 in the fuel system if you install it yourself.

    When you start talking cam swap, you need a gasket set, oil, coolant, timing chain, lifters and cam at a minimum. If valve springs are not improved, gains will be small. Does the engine have adjustable valve train? If not, you are limited to around .420 lift. Everything considered, a cam change can make a 40 hp difference, but not a 125hp difference on an otherwise stock motor. 

  9. I might add, I found my vapor lock issue was the fuel heating in the mechanical fuel pump prior to the EFI install. Everything else i tried did not correct the issue, the EFI did. Gasoline at vacume, being sucked in by the mechanical pump way up front  on the engine, can cause the fuel to boil at less than 90F. Vapor doesn't pump thru a mechanical pump.. Boiling gasoline at 60 psi has to be near 300F. This why new cars don't vapor lock, since they all have intank pumps and a 6" or less suction line, the rest is pressurized fuel line.

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  10. I did clean up the wires some, wrapped then in flexable conduit. I'm a fan of things looking stock. I ran the power wire (Ron Francis 10 Gauge relay kit FP36) inside the passenger fender, into the car where the radio antenna enters, thru the cars wiring channel inside the floor, to the trunk. Here I installed the Ron Francis crash relay that disconnects power to the pump if the car is impacted.  The holley system shuts the pump down if the engine isn't spinning. This all hooked up to the battery and is essentially invisible, as its under the fender, or routed thru the car. I do not believe in running the pump wire outside the car underneath for a lot of reasons.

  11. I needed 60 lbs of fuel pressure at all times with the Sniper.  Its nearly impossible to find a external location to mount a fuel pump lower than the tank as suggested, plus I did not want to hear it. So. I ordered from Butler  Tanks tan-tm32bn-t fuel tank with internal 400 lph pump as they recommend. Installation was easy, bolt in. You cannot see or hear the pump, and it works grear. No more vapor lock, no fuel smell in the garage, and cold starts like a new car every time. By installing the regulator at the tank, i didn't have to install but a 6 inch return line, and reused the factory 3/8 fuel line to supply the engine 60 psi fuel.

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  12. Petronix is great when new. However, they fail often. When you run a hei you can get any part anywhere for it. When your petronix module frys, and they all do, you are stuck until summit or jegs can overnight you one. There is no performance advantage, the hei is superior in every way. Research it. Pontiac knew what they were doing. Larger cap, less crossfire. More amps to the plugs = wider gap= more power.

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