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which cam to choose...

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by reddog64, Oct 11, 2001.

  1. reddog64

    reddog64 1/2 ton status

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    I know this has been covered but...
    I've got a small block 350.. performer intake... 650 carb... and I need a good off-road cam... aka-good low rpm torque...

    PLease advise...
    I'm not partial to any specific brands so... suggest away!!!
     
  2. KRAZIE87K5

    KRAZIE87K5 1/2 ton status

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    Check out my FTP SITE (copy and paste: ftp://CK5@24.10.209.54), and download engine analyzer. Then you can plug in your combo, and play with all different cam specs. Let us know what you find! I would start with CompCams. My new BBC cam PN 11-206-3 is going to make huge power for me. I can't wait to start her up again...! Let me know if you need any help with the software.

    Good luck!

    <font color=red>GOT MUD???</font color=red>
    My license plate reads:
    <font color=blue>8 YRSUV</font color=blue>
    <a target="_blank" href=http://24.10.209.54/bigolk5.htm>http://24.10.209.54/bigolk5.htm</a>
    454/TH400/NP205 - 14BFF/D60/w/ 4.10s
     
  3. Mr.Chevy4x4

    Mr.Chevy4x4 1/2 ton status

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    Summit has a good house brand cam that is fairly cheap that is a dual pattern design. I woul personally go with the 214-224 degrees duration at .050 valve lift with .442-.465 valve lift. I have had very good service out of this cam. Just my $.02.

    '85 K5 : Run it til it breaks, then fix it and go again!
     
  4. tRustyK5

    tRustyK5 Big meanie Staff Member Super Moderator GMOTM Winner Author

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    I plugged in all my numbers for curiousity...9 to 1 350, with the 260H cam from comp cams. 292 lb/ft of torque by 2000 rpm and peak torque was 376 @ 4000 HP peaked at 313 @ 4500.

    Rene


    <font color=green>Dyslexics of the world...UNTIE!</font color=green>
     
  5. chevyboy24598

    chevyboy24598 1/2 ton status

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    Cool deal! It shows that I'm making 450hp and 423 torque! I didn't expect that much.....


    Rust=Good
    <a target="_blank" href=http://www.bodatious.com> bodatious </a>
    <a target="_blank" href=http://www.mudboggingfun.homestead.com> my site </a>
     
  6. Mr.Chevy4x4

    Mr.Chevy4x4 1/2 ton status

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    You have to take the numbers that the software gives you with a grain of salt. I have seen cases where the actual dyno numbers were close to the same as the software, and I have seen many more cases where the dyno numbers were far lower than what the software claimed. I am a software engineer by trade, and I don't think anyone will ever be able to factor all of the variables into a "desktop dyno". Just my $.02.

    '85 K5 : Run it til it breaks, then fix it and go again!
     
  7. 84_Chevy_K10

    84_Chevy_K10 Banned

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    The Summit in house cam is probably pretty good, but taking advantage of the new technology offered by other companies can net a whole lot of gain in HP. It's impossible to try everything close to what will work, but if you think about all your other engine/vehicle specs, it's a little easier to make a more educated decision.

    I chose the Comp Xtreme 4x4 250/258 grind, 206/214 duration @ .050", .432/.453 lift, 111 LSA. It is installed in a 305 with a few other goodies and DD 2000 puts it at 247 HP @ 4500 and 330 ft-lbs @ 3000. That's with a 500 cfm Edelbrock carb, too.

    Tim
    '84 Chevy K10, lifted, loud, fast, and 3/4 ton axles
     
  8. KRAZIE87K5

    KRAZIE87K5 1/2 ton status

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    Don't get me wrong Mr.Chevy4x4, but the software will give you a fairly good impression of how a cam would react to your engine combination. The final numbers may not be 100%, but you can see how the curves change when different cam specs are inserted....

    <font color=red>GOT MUD???</font color=red>
    My license plate reads:
    <font color=blue>8 YRSUV</font color=blue>
    <a target="_blank" href=http://24.10.209.54/bigolk5.htm>http://24.10.209.54/bigolk5.htm</a>
    454/TH400/NP205 - 14BFF/D60/w/ 4.10s
     
  9. Mr.Chevy4x4

    Mr.Chevy4x4 1/2 ton status

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    I agree with you to a point. My point was that there are many other factors that effect power production that the software packages that I have seen don't take into account. For example: port and combustion chamber design can have a huge impact on horsepower. I have seen 40 horsepower increase just changing from TBI heads to Vortec heads with no other changes. What I don't like seeing are these guys that boast 450 H.P. from their 350. I know it can be done, but not without considerable cost and modifications. Making this much power with a 350 moves the power band way up the RMP range which is not the hot ticket for most 4x4's. Just from knowledge and experience I can usually come closer to the actual numbers from a dyno session that the desktop dyno produces. I have seen too many kids overcam a motor because the desktop dyno said they would make more H.P.

    '85 K5 : Run it til it breaks, then fix it and go again!
     
  10. tRustyK5

    tRustyK5 Big meanie Staff Member Super Moderator GMOTM Winner Author

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    Using the software was what convinced me that a smaller cam is the hot ticket sometimes. KRAZIE87K5 has a 454 that was not living up to expectations...we used the software to input his current numbers to obtain a 'cyber' baseline and then changed nothing but the bumpstick and did some camparisons. My original thoughts as to what would be a good cam were close...but going even a step milder resulted in a flatter torque curve and better numbers down low where they help the most.
    I think a lot of motors get 'overcammed' by lack of research and basing the decision on what the cam catalog says about idle quality. The software may not be as accurate as a real dyno but it can make good comparisons of certain components.

    Rene

    <font color=green>Dyslexics of the world...UNTIE!</font color=green>
    <a target="_blank" href=http://coloradok5.com/gallery/project_T2> tRusty pics...</a>
     

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