[DeTomaso] Rocker Arms

Brian Dudley bd8134 at gmail.com
Tue Mar 10 09:11:54 EDT 2015


I am using 3/8" Comp Cams Hi-Tech pushrods with no interference using the
Yella Terra rockers.
YMMV.


On Tue, Mar 10, 2015 at 12:46 AM, doug351c <doug351c at gmail.com> wrote:

>  Brian,
>
> I had a wrong dimension for the pushrods in my first email.  I meant to
> say that you have to be careful when you use 3/8" dia pushrods which are
> larger than the stock 5/16" pushrods.
> It's not the 7/16" studs that cause the rocker binding problem with high
> lift cams.  Most every roller rocker has plenty of rocker stud clearance
> for high lift cams.  But not all of them are properly clearanced for use
> with larger diameter pushrods when using high lift cams.  The side of
> a larger 3/8" diameter pushrod can bind against the backside of the rocker
> body at near full lift.
>
> Doug Braun
> blue 73L #5505
>
> -----Original Message-----
> *From:* Brian Dudley [mailto:bd8134 at gmail.com]
> *Sent:* Monday, March 09, 2015 12:28 PM
> *To:* doug351c at gmail.com
> *Cc:* mark skwarek; Tony DiGiovanna; detomaso
> *Subject:* Re: [DeTomaso] Rocker Arms
>
> As per George Pence's sticky..
> "If your motor’s cylinder heads are milled and tapped for 7/16” stud &
> guide plate type rocker arms the Yella Terra YT-6321 rocker arm is the hot
> tip. This very rugged rocker arm also performs like a shaft mounted rocker
> arm therefore it requires no studs, guide plates or hardened push rods.
> Internet pricing for the Yella Terra YT-6321 rocker arm is in the range of
> $650 US dollars for a set of 16, sometimes even lower. That may look
> "pricey" up front when compared to the standard push-rod guided arm, but
> they don't require studs, guide plates, poly-locks or heat treated
> push-rods. Once you add up the price for a set of conventional roller
> rocker arms plus all the additional stuff you need the price difference is
> not that bad ... some guys feel it is break-even."
> I am using these with a solid cam with the same lift.
> Stock valve cover fits.
> Using a rocker that you have to modify sounds like it is designed for a
> lower lift.
>
> On Sun, Mar 8, 2015 at 10:49 PM, doug351c <doug351c at gmail.com> wrote:
>
>>    i>>?
>>
>>    Yep Mark - that can't be empahsized too much.  That's why I said the
>>    backside may need to be clearanced. (it bit me too !!!)
>>
>>
>>
>>    Doug
>>
>>    -----Original Message-----
>>    From: mark skwarek [mailto:ehpantera at yahoo.com]
>>    Sent: Sunday, March 08, 2015 6:34 PM
>>    To: doug351c at gmail.com; Tony DiGiovanna; detomaso at poca.com
>>    Subject: Re: [DeTomaso] Rocker Arms
>>
>>    Just make sure that you have clearance between the pushrod and the
>>    rocker base at full lift. Under high lift the pushrod can make contact
>>    with the base of the rocker arm. Them the end of the rocker arm end
>>    will break off. Been there, done that.
>>    Mark
>>    On Sunday, March 8, 2015 9:48 PM, doug351c <doug351c at gmail.com> wrote:
>>    I like the Scorpion Endurance SCP3023 1.73:1 forged aluminum roller
>>    rockers.
>>    They have a hardened insert seat, the shaft is centerless ground, a
>>    7/16"
>>    poloc nut is included and they have a great lifetime warranty.  $326 a
>>    set
>>    at Summit Racing.
>>    Max spring dia = 1.625"
>>    [1]http://www.summitracing.com/parts/scc-scp3023bl
>>    I'm running these on my 70 Cleveland Mach1 engine.  Please note though
>>    that
>>    if you intend to run 7/16" dia pushrods, their backsides need to be
>>    clearance for them.  Scorpion's Endurance series cost more than the
>>    Race
>>    series but they have a narrower body and shorter polylocks so they fit
>>    better under stock rocker covers.
>>    Doug Braun
>>    blue 73L #550
>>    -----Original Message-----
>>    From: DeTomaso [mailto:[2]detomaso-bounces at poca.com]On Behalf Of Tony
>>    DiGiovanna
>>    Sent: Sunday, March 08, 2015 4:00 PM
>>    To: [3]detomaso at poca.com
>>    Subject: [DeTomaso] Rocker Arms
>>    351C, solid flat tappet cam with lift of 0.640.  7/16 screwed-in
>>    studs.  Any
>>    opinions on Rock Arms? PRW vs. Harland Sharp vs. other?
>>    _______________________________________________
>>    Detomaso Forum Managed by POCA
>>    Posted emails must not exceed 1.5 Megabytes
>>    DeTomaso mailing list
>>    [4]DeTomaso at poca.com
>>    [5]http://poca.com/mailman/listinfo/detomaso_poca.com
>>    To manage your subscription (change email address, unsubscribe, etc.)
>>    use the links above.
>>
>> References
>>
>>    1. file://localhost/tmp/tmpfWSGk7.html
>>    2. file://localhost/tmp/tmpfWSGk7.html
>>    3. file://localhost/tmp/tmpfWSGk7.html
>>    4. file://localhost/tmp/tmpfWSGk7.html
>>    5. file://localhost/tmp/tmpfWSGk7.html
>>
>> _______________________________________________
>>
>> Detomaso Forum Managed by POCA
>> Posted emails must not exceed 1.5 Megabytes
>> DeTomaso mailing list
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>> http://poca.com/mailman/listinfo/detomaso_poca.com
>>
>> To manage your subscription (change email address, unsubscribe, etc.) use
>> the links above.
>>
>>
>
-------------- next part --------------
   I am using 3/8" Comp Cams Hi-Tech pushrods with no interference using
   the Yella Terra rockers.
   YMMV.

   On Tue, Mar 10, 2015 at 12:46 AM, doug351c <[1]doug351c at gmail.com>
   wrote:

   Brian,
   A
   I had a wrong dimension for the pushrods in my first email.A  I meant
   to say that you have to be careful when you use 3/8" dia
   pushrodsA which are larger than the stock 5/16" pushrods.A A
   It's not the 7/16" studs that cause the rocker binding problem with
   high lift cams.A  Most every roller rocker has plenty of rocker stud
   clearance for high lift cams.A A But not all of them are properly
   clearanced for use with larger diameter pushrods when using high lift
   cams.A  The side of aA larger 3/8" diameter pushrod canA bind against
   the backside of theA rocker body at near full lift.A A
   A
   Doug Braun
   blue 73L #5505A A A

   -----Original Message-----
   From: Brian Dudley [mailto:[2]bd8134 at gmail.com]
   Sent: Monday, March 09, 2015 12:28 PM
   To: [3]doug351c at gmail.com
   Cc: mark skwarek; Tony DiGiovanna; detomaso
   Subject: Re: [DeTomaso] Rocker Arms

   As per George Pence's sticky..
   "If your motoras cylinder heads are milled and tapped for 7/16a stud &
   guide plate type rocker arms the Yella Terra YT-6321 rocker arm is the
   hot tip. This very rugged rocker arm also performs like a shaft mounted
   rocker arm therefore it requires no studs, guide plates or hardened
   push rods. Internet pricing for the Yella Terra YT-6321 rocker arm is
   in the range of $650 US dollars for a set of 16, sometimes even lower.
   That may look "pricey" up front when compared to the standard push-rod
   guided arm, but they don't require studs, guide plates, poly-locks or
   heat treated push-rods. Once you add up the price for a set of
   conventional roller rocker arms plus all the additional stuff you need
   the price difference is not that bad ... some guys feel it is
   break-even."
   I am using these with a solid cam with the same lift.
   Stock valve cover fits.
   Using a rocker that you have to modify sounds like it is designed for a
   lower lift.

   On Sun, Mar 8, 2015 at 10:49 PM, doug351c <[4]doug351c at gmail.com>
   wrote:

     A  A i>>?
     A  A Yep Mark - that can't be empahsized too much.A  That's why I
     said the
     A  A backside may need to be clearanced. (it bit me too !!!)
     A  A Doug
     A  A -----Original Message-----
     A  A From: mark skwarek [mailto:[5]ehpantera at yahoo.com]
     A  A Sent: Sunday, March 08, 2015 6:34 PM
     A  A To: [6]doug351c at gmail.com; Tony DiGiovanna;
     [7]detomaso at poca.com
     A  A Subject: Re: [DeTomaso] Rocker Arms
     A  A Just make sure that you have clearance between the pushrod and
     the
     A  A rocker base at full lift. Under high lift the pushrod can make
     contact
     A  A with the base of the rocker arm. Them the end of the rocker arm
     end
     A  A will break off. Been there, done that.
     A  A Mark
     A  A On Sunday, March 8, 2015 9:48 PM, doug351c
     <[8]doug351c at gmail.com> wrote:
     A  A I like the Scorpion Endurance SCP3023 1.73:1 forged aluminum
     roller
     A  A rockers.
     A  A They have a hardened insert seat, the shaft is centerless
     ground, a
     A  A 7/16"
     A  A poloc nut is included and they have a great lifetime
     warranty.A  $326 a
     A  A set
     A  A at Summit Racing.
     A  A Max spring dia = 1.625"
     A  A [1][9]http://www.summitracing.com/parts/scc-scp3023bl
     A  A I'm running these on my 70 Cleveland Mach1 engine.A  Please
     note though
     A  A that
     A  A if you intend to run 7/16" dia pushrods, their backsides need
     to be
     A  A clearance for them.A  Scorpion's Endurance series cost more
     than the
     A  A Race
     A  A series but they have a narrower body and shorter polylocks so
     they fit
     A  A better under stock rocker covers.
     A  A Doug Braun
     A  A blue 73L #550
     A  A -----Original Message-----
     A  A From: DeTomaso [mailto:[2][10]detomaso-bounces at poca.com]On
     Behalf Of Tony
     A  A DiGiovanna
     A  A Sent: Sunday, March 08, 2015 4:00 PM
     A  A To: [3][11]detomaso at poca.com
     A  A Subject: [DeTomaso] Rocker Arms
     A  A 351C, solid flat tappet cam with lift of 0.640.A  7/16
     screwed-in
     A  A studs.A  Any
     A  A opinions on Rock Arms? PRW vs. Harland Sharp vs. other?
     A  A _______________________________________________
     A  A Detomaso Forum Managed by POCA
     A  A Posted emails must not exceed 1.5 Megabytes
     A  A DeTomaso mailing list
     A  A [4][12]DeTomaso at poca.com
     A  A [5][13]http://poca.com/mailman/listinfo/detomaso_poca.com
     A  A To manage your subscription (change email address, unsubscribe,
     etc.)
     A  A use the links above.
     References
     A  A 1. file://localhost/tmp/tmpfWSGk7.html
     A  A 2. file://localhost/tmp/tmpfWSGk7.html
     A  A 3. file://localhost/tmp/tmpfWSGk7.html
     A  A 4. file://localhost/tmp/tmpfWSGk7.html
     A  A 5. file://localhost/tmp/tmpfWSGk7.html
     _______________________________________________
     Detomaso Forum Managed by POCA
     Posted emails must not exceed 1.5 Megabytes
     DeTomaso mailing list
     [14]DeTomaso at poca.com
     [15]http://poca.com/mailman/listinfo/detomaso_poca.com
     To manage your subscription (change email address, unsubscribe,
     etc.) use the links above.

References

   1. mailto:doug351c at gmail.com
   2. mailto:bd8134 at gmail.com
   3. mailto:doug351c at gmail.com
   4. mailto:doug351c at gmail.com
   5. mailto:ehpantera at yahoo.com
   6. mailto:doug351c at gmail.com
   7. mailto:detomaso at poca.com
   8. mailto:doug351c at gmail.com
   9. http://www.summitracing.com/parts/scc-scp3023bl
  10. mailto:detomaso-bounces at poca.com
  11. mailto:detomaso at poca.com
  12. mailto:DeTomaso at poca.com
  13. http://poca.com/mailman/listinfo/detomaso_poca.com
  14. mailto:DeTomaso at poca.com
  15. http://poca.com/mailman/listinfo/detomaso_poca.com


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