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1.5 or 1.6 rockers ?

Discussion in 'The Garage' started by y5mgisi, Jun 8, 2003.

  1. y5mgisi

    y5mgisi 1 ton status

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    How can i see if i have the 1.5 or 1.6's on my truck? is it realy worth it to have the 1.6's or arethe 1.5's plenty fine. /forums/images/graemlins/confused.gif
     
  2. fortcollinsram

    fortcollinsram 1/2 ton status

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    is your engine stock? if so you have 1.5...a higher ratio rocker equates to more valve lift than stock rockers at a given amount of cam lift. it can be beneficial, but I wouldn't spend the money ot get higer ratio rockers unless you are doing lots of other things, like a cam, headers, intkae, etc...For example, on my 454 that I build for my K5, I have the stock ratio rockers but in a roller version...I personally feel that there is a greater benefit to going with roller rocers than a higher ratio rocker...

    Chris
     
  3. blasterD

    blasterD 1/2 ton status

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    I agree with fortcollinsram. You may see a little gain by going to the 1.6 rockers a stock cam , but most aftermarket cams are designed to work the best with 1.5 rockers. You also need to consider piston-valve interference with an aftermarket cam and 1.6 rockers.
     
  4. BlazerGuy

    BlazerGuy 3/4 ton status

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    Yep, 1.5s are stock fer small blocks...
     
  5. Mreetz

    Mreetz 1/2 ton status

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    I went with 1.5s worked out great!
     
  6. y5mgisi

    y5mgisi 1 ton status

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    See thats the thing is that i know the motor is modified but I dont know if theyt put diffrent rocks in when they did all the other work. (it was done in 1990). and the cam im running is about the smallest one you can get(252h comp cams) so it has veary little lift and duration. So i figured bumping up the rockers would give it more lift and duration making it seem like a bigger cam. Am I crazy or was i misinformed about the benifits of 1.6 rockers? /forums/images/graemlins/1zhelp.gif
     
  7. BowtieRed

    BowtieRed 1/2 ton status Author

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    extra money????? what? they close the same price

    851-1001 1.5 Ratio, 3/8'' Stud (16/pkg.) $182.99
    851-1002 1.6 Ratio, 3/8'' Stud (16/pkg.) $197.99
    with some dich pistons, or ones cut to avoid interference and a high lift cam they can be very beneficial.
     
  8. y5mgisi

    y5mgisi 1 ton status

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    Do you think I have enough clearnce sence im running that small cam I think it would be OK.
     
  9. BowtieRed

    BowtieRed 1/2 ton status Author

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    what pistons are you running? if they are inverted dish i wouldn't risk it, if flat top then you should be OK
     
  10. y5mgisi

    y5mgisi 1 ton status

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    I have no idea. I know the comp ratio is up about .5 of what it was before motor mork .I could probly call dad and ask him he might remember.
     
  11. SUBFAN

    SUBFAN 1/2 ton status

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    From the description of your motor, there is a very good chance that the 1.6 rockers will work fine. Don't expect a huge difference with the but-crack dyno though.

    Try pulling one of the old rockers off and looking it over carefully, the ratio might be stamped on it. If you don't see a ratio stamped on it, then more than likely it is a factory 1.5 . With a basic rebuild, most people don't even bother to change the rockers. I used Cam Dynamics aluminum roller rockers, made by Crane, and cheaper too. I've used two sets with no problems.

    Aftermarket rockers are more accurate than factory ones, but at this level I don't feel they are necessary.

    If you are looking for 'bang for your buck' then go with a set of headers and a free flowing exhaust. That but-crack dyno WILL notice that mod. /forums/images/graemlins/grin.gif
     
  12. sled_dog

    sled_dog 1 ton status

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    I would rather run flat tops and 1.5s than dished and 1.6s. Higher compression will bring better gains than that lift change in almost all conditions. Only time I would do it is if I was somehow already running like 12:1 and it would just bump me down to like 11:1. but higher compression can be higher fuel octane needs.
     
  13. y5mgisi

    y5mgisi 1 ton status

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    Well thanks for all the info guys. sounds like i'll just stick with what i got. as for the headers that will be tough because i have a PTO winch that runs off my 205 tansfer case, so the drive shaft for it is right in the way of where the headers will need to be /forums/images/graemlins/mad.gif
     
  14. sled_dog

    sled_dog 1 ton status

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    shortys? won't be as big an improvement as long tubes but still better then them big heavy blocks of steel they cast in the plant
     

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