Installing roller rocker ?????????
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Joined: Dec 2009
Posts: 73
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From: N. Little Rock Arkansas
Installing roller rocker ?????????
I got the self aligning 1.6 roller rockers for my '89 L98. I already have Bosch II injectors. What kind of performance boost( if any ) can I expect after changing out my stock rockers to the full rollers? I have the factory D44 with 3.33 gear, and the six speed was swapped for an automatic by the previous owner.
Instructor
Joined: Dec 2009
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From: New Jersey
Thread Starter
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Joined: Dec 2009
Posts: 73
Likes: 1
From: N. Little Rock Arkansas
Thanks for the responses. I decided to put some rollers in since I'm taking the intake off to fix the leak from the manifold gasket. I figured I'd try something that wasn't too difficult while the car was apart. I'll let ya'll know how it goes. Later.
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Team Owner
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From: Phila., PA burbs
Advanced
Joined: Feb 2010
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I got the self aligning 1.6 roller rockers for my '89 L98. I already have Bosch II injectors. What kind of performance boost( if any ) can I expect after changing out my stock rockers to the full rollers? I have the factory D44 with 3.33 gear, and the six speed was swapped for an automatic by the previous owner.
1.5 Ratio Bow Tie Roller GM Performance Parts Rocker Arms
Part Number: 12370838
Do you know if they will fit under stock valve covers?
Racer
Joined: Sep 2010
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From: Epfenbach BW
I did the Scorpion 1.6 Self aligning RR when I had to do my head gasket.
I also had the valves done and installed LT4 springs.
I certainly DO feel a difference but may also be a combination of all the other new parts I added....
I also had the valves done and installed LT4 springs.
I certainly DO feel a difference but may also be a combination of all the other new parts I added....
Racer
Joined: Sep 2010
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From: Epfenbach BW
They fit under the stock valve covers btw. But I grinded the oil drip thingies and the sides of the center posts where the bolt goes through.
I did not check for clearance but did the grinding as a precaution as I waited for the parts to arrive.
I did not check for clearance but did the grinding as a precaution as I waited for the parts to arrive.
Race Director
Joined: Aug 2000
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pound for pound, pony for pony - give me more low end torque over upper rpm horsepower any day!
Intermediate
Joined: Jan 2011
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From: San ANtonio Texas
If you want a little more low end torque vs. high end horsepower, advance your cam to on @ 4 degrees. Be sure to check VTC clearance!!!!
My opinion on 1.6 rockers.....valvetrain geometry has many variables. Match your cam to your rockers and make sure your springs are suitable. Always check valve to cylinder clearance when you change your geometry :>)
My opinion on 1.6 rockers.....valvetrain geometry has many variables. Match your cam to your rockers and make sure your springs are suitable. Always check valve to cylinder clearance when you change your geometry :>)
Racer
Joined: Nov 2010
Posts: 460
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From: Oliphant Ontario
A little more timing (and premium to go with it) will probably add a bit.
The rockers might, I added 1.6's to mine but still have white crap on the ground so can't see what they did. I did read a number of dyno results that varied from no gain to 15hp on various motors (none were TPI though). Also found conflicting results on same motors using mixed 1.5/1.6 and all 1.6 so it is clearly a crap shoot.
A little more breathing out its butt will help some, IMO especially doing something with the pre-cats. X over might. Small diameter long tube headers might (but existing is small tube short so very little gain potential). Larger diameter long tubes will help up higher but may hurt off idle that you're looking for.
Chipping to a small degree. Cam can make a big change but a low end torque cam isn't known to extend the high end and visa/versa. Port matching the heads and intake.
Most things to add low end torque will not help higher RPM, some will hurt it, some help across the board.
The nice thing about torque numbers in the 2500 range is you will feel changes there more so than the same amount at say 4800..
The rockers might, I added 1.6's to mine but still have white crap on the ground so can't see what they did. I did read a number of dyno results that varied from no gain to 15hp on various motors (none were TPI though). Also found conflicting results on same motors using mixed 1.5/1.6 and all 1.6 so it is clearly a crap shoot.
A little more breathing out its butt will help some, IMO especially doing something with the pre-cats. X over might. Small diameter long tube headers might (but existing is small tube short so very little gain potential). Larger diameter long tubes will help up higher but may hurt off idle that you're looking for.
Chipping to a small degree. Cam can make a big change but a low end torque cam isn't known to extend the high end and visa/versa. Port matching the heads and intake.
Most things to add low end torque will not help higher RPM, some will hurt it, some help across the board.
The nice thing about torque numbers in the 2500 range is you will feel changes there more so than the same amount at say 4800..
Thread Starter
Advanced
Joined: Dec 2009
Posts: 73
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From: N. Little Rock Arkansas
If you want a little more low end torque vs. high end horsepower, advance your cam to on @ 4 degrees. Be sure to check VTC clearance!!!!
My opinion on 1.6 rockers.....valvetrain geometry has many variables. Match your cam to your rockers and make sure your springs are suitable. Always check valve to cylinder clearance when you change your geometry :>)
My opinion on 1.6 rockers.....valvetrain geometry has many variables. Match your cam to your rockers and make sure your springs are suitable. Always check valve to cylinder clearance when you change your geometry :>)
Advanced
Joined: Mar 2010
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From: Grove Oklahoma
Thanks for all the information about adding torque. I appreciate it. I am not looking for better 1/4 mile times, just looking at stoplight getup and go type street drag racing. In case someone pulls up alongside such as a mustang or something. I just have an L83. I know rear gears would really help in that area.
