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Max Lift outta a stock 305

Discussion in 'The Garage' started by BigBurban350, May 14, 2003.

  1. BigBurban350

    BigBurban350 1/2 ton status

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    What is the maximum lift that I can get outta a stock 305 setup? Im hoping to get .6 outta both intake and exhaust. /forums/images/graemlins/usaflag.gif /forums/images/graemlins/burb.gif /forums/images/graemlins/usaflag.gif
     
  2. dyeager535

    dyeager535 1 ton status Premium Member

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    Sorry, can't help myself.

    [ QUOTE ]
    Golden rule #1: There is no replacement for DISPLACEMENT!

    [/ QUOTE ]

    /forums/images/graemlins/smile.gif
     
  3. Shaggy

    Shaggy 3/4 ton status

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    <font color="green"> What the hell kind of drag racing cam are you going to use!? Seems to me that any cam with that kind of lift is going to seriously suck at anything below 3000 RPM or so; that doesn't seem quite right for a 4x4. </font>
     
  4. Hossbaby50

    Hossbaby50 3/4 ton status

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    It should have about 3 ft of lift. You then pull it over the radiator support and put it in the trash. Then install a real motor.

    Seriously though. I can't help you on max lift. I can't imagine it is near .6 though. 305's were never motors ment for performance so I don't think they would have been designed with that much lift possibility.
     
  5. BigBurban350

    BigBurban350 1/2 ton status

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    [ QUOTE ]
    <font color="green"> What the hell kind of drag racing cam are you going to use!? Seems to me that any cam with that kind of lift is going to seriously suck at anything below 3000 RPM or so; that doesn't seem quite right for a 4x4. </font>

    [/ QUOTE ]

    This is how I figured that. I plugged in all stock specs into Dyno2000, then I iterated the best cam and lift for max horsepower between 2000 to 3500 rpms. There was something like 2 million combinations to test so I ran it all last night. It came up with like 272 and 280 durations with .6 lift on intake and .59 lift on exhaust.

    I just want the most horsepower the cheapest way, so I just want to put on headers and a cam, probably a new carb too. /forums/images/graemlins/usaflag.gif /forums/images/graemlins/burb.gif /forums/images/graemlins/usaflag.gif
     
  6. BigBurban350

    BigBurban350 1/2 ton status

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    [ QUOTE ]
    It should have about 3 ft of lift. You then pull it over the radiator support and put it in the trash. Then install a real motor.

    Seriously though. I can't help you on max lift. I can't imagine it is near .6 though. 305's were never motors ment for performance so I don't think they would have been designed with that much lift possibility.

    [/ QUOTE ]

    I am a broke ass college student who needs to do things in the cheapest way possible /forums/images/graemlins/smile.gif, so my only option it to build the engine that I already have. If I was outta school with a real job, or had parents that give their kids spending money then I would have a built 350 with all the bells and whistles. For now I will be doing the best with what I got.
     
  7. Hossbaby50

    Hossbaby50 3/4 ton status

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    I hear you. I am a college student too with little cash. Start with the easy stuff first. Exhaust and intake. Put on an Edelbrock aluminum manifold to let it breath better and some headers. Then when money allows cam, full exhaust, etc.
     
  8. HarryH3

    HarryH3 1 ton status Author

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    The problem is, that the program didn't take your budget into account. /forums/images/graemlins/eek.gif The only cams that I know of off-hand that get into that kind of lift are full-on roller cams and use solid roller lifters. You would also have to do extensive machine work to the heads and use special valve springs that could handle that much lift. I'd guesstimate that just for the valvetrain parts and head work, you would easily be spending $1,500 or more. /forums/images/graemlins/shocked.gif

    Now, bringing things back into reality... The tech line for CompCams or Crane Cams can help you find a cam that will work within the restraints of your current engine and still make a noticable improvement. /forums/images/graemlins/thumb.gif
     
  9. 88Silverado

    88Silverado 1/2 ton status

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    With stock 305 heads I wouldnt push more than .460
    305 heads pretty much suck when it comes to flow. Thats why the program works with .6 lift, reallllly need to get the valve open. You would be better off finding some old 350 882's or something. Do you have the head numbers??
     
  10. big pappa b

    big pappa b 3/4 ton status

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    If you put a cam near .5 or more in there I can guarantee that you will be pulling the studs out of the heads. Maybe a .46 -.48 at the very most. Save up your money and build a motor the right way
     
  11. 88Silverado

    88Silverado 1/2 ton status

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    Several months ago Car Craft magazine did a comparison of a "Bolt-On" performance 350 with the same parts on a 305. Results were pretty impressive. Might want to find that article and see what they did. As posted above, call comp or crane cams and get their suggestions
     
  12. 88Silverado

    88Silverado 1/2 ton status

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    Several months ago Car Craft magazine did a comparison of a "Bolt-On" performance 350 with the same parts on a 305. Results were pretty impressive. Might want to find that article and see what they did. As posted above, call comp or crane cams and get their suggestions
     
  13. dyeager535

    dyeager535 1 ton status Premium Member

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    Here's a fairly old 305 build up:

    http://dyeager535.topcities.com/305.html

    You'll be better off saving your money and spending it on a 350. You can get power with a 305, but as with any other CID change, the exact same changes on a larger motor will make more power, easier.
     
  14. BigBurban350

    BigBurban350 1/2 ton status

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    Yeah, I guess that much lift is excessive. I re-did the iterater test with it set at .454 lift for best TORQUE between 2000-3500 rpms: I got a nice flat torque curve of 300 ftlbs dropping off at 4500 and got a peak hp of 274 at 5000 rpms. Thats with just a cam(dur in:271 ex:281) and small tube headers! Thats only $250 in mods /forums/images/graemlins/thumb.gif!
     
  15. dyeager535

    dyeager535 1 ton status Premium Member

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    $250 isn't too bad I guess.

    Then again, probably get you into a roller 350 core for that kind of money /forums/images/graemlins/tongue.gif
     
  16. sdavid

    sdavid 1/2 ton status

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    I think 2000rpms is a little high to want your motor to start making power. You would also need to add a stall convertor to your budget. You'll find that pretty mild cam grinds do the best on torque and if you have a burb to pull around, torque is where it is at. Look at diesel motor specs to get some ideas of what moves heavy rigs around.
     
  17. 88Silverado

    88Silverado 1/2 ton status

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  18. BigBurban350

    BigBurban350 1/2 ton status

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    [ QUOTE ]
    I think 2000rpms is a little high to want your motor to start making power. You would also need to add a stall convertor to your budget. You'll find that pretty mild cam grinds do the best on torque and if you have a burb to pull around, torque is where it is at. Look at diesel motor specs to get some ideas of what moves heavy rigs around.

    [/ QUOTE ]

    This engine is for a blazer frame w/ an s-10 cab(plannin on it) so itll be very light.
     
  19. HarryH3

    HarryH3 1 ton status Author

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    Dyno 2000 also doesn't let you do any calculations below 2,000 RPM. That could be part of why he selected the RPM range that he posted. /forums/images/graemlins/wink.gif
     
  20. sdavid

    sdavid 1/2 ton status

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    Well is it a rock crawler or a mud racer? That will help you decide what cam you want. The application of the rig is going to be the biggest deciding factor in cam selection, not just the biggest you can get. You would not want to be roasting the tires at 35 grand trying to climb an off camber boulder, but you would want all that power trying to fly through a mud pit. Just some things to think about.
     

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