Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

  1. chevyboy24598

    chevyboy24598 1/2 ton status

    Joined:
    Jul 17, 2001
    Posts:
    212
    Likes Received:
    0
    Location:
    Va, USA
    My tach reads 1500 at idle and runs all the way over to 8000.(all I got is a 8000rpm tach) Is my tach way off or is it right for a built 350?

    <a target="_blank" href=http://www.pinelanemuddbogg.com> pinelane </a>

    <a target="_blank" href=http://www.bodatious.com> bodatious </a>
     
  2. beater74

    beater74 1/2 ton status

    Joined:
    May 29, 2001
    Posts:
    1,749
    Likes Received:
    0
    Location:
    atlanta
    8000 rpm out of a 350, that sound like it's way past the red line, i think somthing is wrong there.
     
  3. chevyboy24598

    chevyboy24598 1/2 ton status

    Joined:
    Jul 17, 2001
    Posts:
    212
    Likes Received:
    0
    Location:
    Va, USA
    Its got a big cam, headers, and holley intake with a carb spacer. Everytime it hits it shakes the truck! I got a TCI 2400-2800 stall, acording to that the tach is 500 rpm behind.

    <a target="_blank" href=http://www.pinelanemuddbogg.com> pinelane </a>

    <a target="_blank" href=http://www.bodatious.com> bodatious </a>
     
  4. newyorkin

    newyorkin 1 ton status

    Joined:
    May 8, 2001
    Posts:
    16,555
    Likes Received:
    157
    Location:
    Los Estados Unitos
    Hmm. Could be a tach for a 4 or 6-cylinder or the wrong setting on the tach. Mine is selectable, and when I reversed the face and body on it (for an old car), the switch read backwards 4-6-8, so I had it in 4 by accident. Freaked me out when I first started the motor with it on...

    I would bet if it's reading that high, it's set for a 4-cylinder, doubling your actual RPM.
    If it's set for a 6-cyl, you're idling at 1125 rpm. At 8000 on the clock, you'd really be at 6750 rpm, still high for a sbc.

    Y'know, I was gonna leave it at "the tach is probably set for the wrong cyl count", but then I wanted to challenge myself to actually figure it out... It's been a loonnnnnng time for me...


    Ratch
    &lt;a target="_blank" href=http://k5.8m.com&gt;k5.8m.com&lt;/a&gt;
    **K5 - What more is there to life?**
     
  5. chevyboy24598

    chevyboy24598 1/2 ton status

    Joined:
    Jul 17, 2001
    Posts:
    212
    Likes Received:
    0
    Location:
    Va, USA
    Look at the winston cup cars, they could cruise at 6750 all day long.

    <a target="_blank" href=http://www.pinelanemuddbogg.com> pinelane </a>

    <a target="_blank" href=http://www.bodatious.com> bodatious </a>
     
  6. tRustyK5

    tRustyK5 Big meanie Staff Member Super Moderator GMOTM Winner Author

    Joined:
    Jul 23, 2000
    Posts:
    36,173
    Likes Received:
    1,385
    Location:
    E-town baby!
    I agree that the tach is either way off or set for a 4 or 6 cylinder...
    I don't doubt that a really built 350 'could' pull 8000 RPM, but I have yet to see it. You would have to be running a 900 CFM or better carb just to feed a 350 pulling 8000 RPM, plus the cam and head work necessary to get it to pull those numbers would be insane.

    My bet is that its set for a 4 cylinder...

    Rene

    <font color=green>Dyslexics of the world...UNTIE!</font color=green>
     
  7. Cusm

    Cusm 1/2 ton status

    Joined:
    Feb 25, 2000
    Posts:
    360
    Likes Received:
    0
    Location:
    OK
    His point was, you are NOT driving a Winston Cup car. 8k is way too high.

    Good lord. The rod up that man's butt must have a rod up it's butt.
     
  8. white_knight

    white_knight 1/2 ton status

    Joined:
    Feb 23, 2001
    Posts:
    1,171
    Likes Received:
    0
    Location:
    Calgary, Alberta,Canada
    Way too high. That doesn't sound right at all

    <a target="_blank" href=http://www.whiteknight.scriptmania.com/>http://www.whiteknight.scriptma
    nia.com
    </a>
     
  9. newyorkin

    newyorkin 1 ton status

    Joined:
    May 8, 2001
    Posts:
    16,555
    Likes Received:
    157
    Location:
    Los Estados Unitos
    6750 is high, but I didn't say or mean to imply impossible, and I wouldn't try to sustain it too long.

    Did you look at the tach? Is it definately an 8-cylinder tach?

    BTW, Winston cup nascar engines are generally built a little different than stock motors, pushing 750 HP at 9000 rpm (about double a stock motor). They are also rebuilt every few races...

    Ratch
    &lt;a target="_blank" href=http://k5.8m.com&gt;k5.8m.com&lt;/a&gt;
    **K5 - What more is there to life?**
     
  10. beater74

    beater74 1/2 ton status

    Joined:
    May 29, 2001
    Posts:
    1,749
    Likes Received:
    0
    Location:
    atlanta
    8000 rpm out of a sbc not on this planet unless you spent $10,000 on that engine and having it built by one of the best engine builders around. get a new tach
     
  11. chevyboy24598

    chevyboy24598 1/2 ton status

    Joined:
    Jul 17, 2001
    Posts:
    212
    Likes Received:
    0
    Location:
    Va, USA
    I didn't build the motor so I dont know, but I can tell you its not stock!

    <a target="_blank" href=http://www.pinelanemuddbogg.com> pinelane </a>

    <a target="_blank" href=http://www.bodatious.com> bodatious </a>
     
  12. tRustyK5

    tRustyK5 Big meanie Staff Member Super Moderator GMOTM Winner Author

    Joined:
    Jul 23, 2000
    Posts:
    36,173
    Likes Received:
    1,385
    Location:
    E-town baby!
    My not stock 350 runs out of usable 'R's at about 4700 RPM. Performance cam, Edelbrock carb etc...

    Its your tach.

    Rene

    <font color=green>Dyslexics of the world...UNTIE!</font color=green>
     
  13. beater74

    beater74 1/2 ton status

    Joined:
    May 29, 2001
    Posts:
    1,749
    Likes Received:
    0
    Location:
    atlanta
    I run a built 350 pushing 350 hp and if i pushed mine to 8000 rpm rod would come shooten out my oil pan and piston out of the hood not to mention it would not be good for the engine. I'm no master engine guru god builder but if someone has a sbc that will run 8000 rpms all day i'd like to see it. i blew my first engine sitting in my drive my, i thought i would be cool and wake up the neigbors by reveing the motor. well i pushed it a little to far and not even close to 8000 rpm and broke the crank shaft in two places.
     
  14. 4x4blazer

    4x4blazer 1/2 ton status

    Joined:
    Jun 14, 2000
    Posts:
    278
    Likes Received:
    0
    Location:
    Louisiana
    If you really think you are gettin 8 grand out of it, you may want to install some scatter blankets on the engine cause it is gonna go kabloom soon. And with that shaking your whole truck thing, check those motor mounts.
     
  15. chevyboy24598

    chevyboy24598 1/2 ton status

    Joined:
    Jul 17, 2001
    Posts:
    212
    Likes Received:
    0
    Location:
    Va, USA
    The motor mounts are in good shape.

    <a target="_blank" href=http://www.pinelanemuddbogg.com> pinelane </a>

    <a target="_blank" href=http://www.bodatious.com> bodatious </a>
     
  16. chevyboy24598

    chevyboy24598 1/2 ton status

    Joined:
    Jul 17, 2001
    Posts:
    212
    Likes Received:
    0
    Location:
    Va, USA
    You were right on the money! I look behind the tack and sure enough it had a setting for a 6 and one for 8. It was on 6, so i changed it to 8. It idles around 1000 and pulls strong til' 7000!

    <a target="_blank" href=http://www.pinelanemuddbogg.com> pinelane </a>

    <a target="_blank" href=http://www.bodatious.com> bodatious </a>
     

Share This Page