I went ahead and did 1.6 all around on mine. I just stayed with self aligning and put in new springs.
Mixing Roller Rockers
Thread Starter
Burning Brakes
Joined: Aug 2006
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From: Rockland County NY
Mixing Roller Rockers
Has anyone heard of mixing 1.5 and 1.6 Roller rockers... I'm replacing a bad lifter (all of them actually) on my 91 L98 and figured while I had it apart, I might as well do an affordable upgrade. A friend suggested mixing them, but I've never heard of that. Does it make sense to you guys and why?
Team Owner
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yes, 1.5 on intake and 1.6 on exhaust suits the L98 just fine
its up to you, i'd go ahead and do 1.6 everywhere
its up to you, i'd go ahead and do 1.6 everywhere
Team Owner
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From: SE NY
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Does it make sense to you guys and why?
I installed 1.6s around on my '88 with #113 heads with very good results; it would also be the recommended path if you have a '91.
Le Mans Master
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From: One day you're a Comet...the next day you're dust... Arkansas
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Burning Brakes
Joined: Aug 2006
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From: Rockland County NY
Thanks guys, there never seems to be a black and white answer to any question! Now, lets say I get the intake off and find out the bad lifter ruined the cam. Will 1.6's affect the performance of an aftermarket cam? And while I'm asking...is there a good cam to use (keeping the stock intake, l/t headers and flowmaster cat-back system) . I'm going to be tackling this project next week hopefully and want to have all the answers before I start.
Team Owner
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From: SE NY
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TPIS several others make nice cams that will work with 1.6:1RRs and single springs. The 1.6:1 RRs will have the same effect on an aftermarket cam as on the stock cam, i.e. they will increase max lift by ~7% and increase duration at .005" by ~2deg.
If you have the valve cover off you can measure lift at the pushrod in question and compare with lift at another lobe to see if the suspected lobe was flattened by the bad lifter.
What was the failure mode of the faulty lifter??
If you have the valve cover off you can measure lift at the pushrod in question and compare with lift at another lobe to see if the suspected lobe was flattened by the bad lifter.
What was the failure mode of the faulty lifter??
Last edited by 65Z01; Apr 4, 2008 at 03:27 PM.
Le Mans Master
Joined: Jun 2006
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From: One day you're a Comet...the next day you're dust... Arkansas
Thanks guys, there never seems to be a black and white answer to any question! Now, lets say I get the intake off and find out the bad lifter ruined the cam. Will 1.6's affect the performance of an aftermarket cam? And while I'm asking...is there a good cam to use (keeping the stock intake, l/t headers and flowmaster cat-back system) . I'm going to be tackling this project next week hopefully and want to have all the answers before I start.
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Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 1,123
Likes: 1
From: Rockland County NY
TPIS several others make nice cams that will work with 1.6:1RRs and single springs. The 1.6:1 RRs will have the same effect on an aftermarket cam as on the stock cam, i.e. they will increase max lift by ~7% and increase duration at .005" by ~2deg.
If you have the valve cover off you can measure lift at the pushrod in question and compare with lift at another lobe to see if the suspected lobe was flattened by the bad lifter.
What was the failure mode of the faulty lifter??
If you have the valve cover off you can measure lift at the pushrod in question and compare with lift at another lobe to see if the suspected lobe was flattened by the bad lifter.
What was the failure mode of the faulty lifter??
Team Owner
Joined: Sep 2001
Posts: 62,146
Likes: 1,730
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Thanks guys, there never seems to be a black and white answer to any question! Now, lets say I get the intake off and find out the bad lifter ruined the cam.
Will 1.6's affect the performance of an aftermarket cam?
And while I'm asking...is there a good cam to use (keeping the stock intake, l/t headers and flowmaster cat-back system) . I'm going to be tackling this project next week hopefully and want to have all the answers before I start.
Will 1.6's affect the performance of an aftermarket cam?
And while I'm asking...is there a good cam to use (keeping the stock intake, l/t headers and flowmaster cat-back system) . I'm going to be tackling this project next week hopefully and want to have all the answers before I start.
1.6s enhance lift specs, so yes they affect performance, generally in a positive way. You need not worry about a case where they would hurt rather than help, just buy them.
Keeping stock TPI intake, or even a modified one, go with Accel 211, or TPiS ZZ9.
Once the cam is changed a new custom chip is needed.
Team Owner
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From: SE NY
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Under a load or over 3k rpm it sounds like my grandmothers old typewriter! I'm only guessing at the lifter
Then you can pull the cover to see if it's a loose lifter.
Have you checked the injectors to see if one of them is noisy?
Thread Starter
Burning Brakes
Joined: Aug 2006
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From: Rockland County NY
no, I didn't know an injector could make that kind of noise. How can I check? Same way?
Team Owner
Joined: Dec 2000
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From: SE NY
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The rubber tube against the ear held to the back of each injector will give you the audable feedback; I just put my finger on the back of the injector connector and feel the vibration.
Racer
Joined: May 2005
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From: looking for my insanity state of confusion
I'll throw in the suggestion to also check the rocker clearances, they might need an adjustment. Or you can just accept the fact that your subconscious is telling to mod it, and just pick up the cam, rockers, and have a blast driving it.
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 1,123
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From: Rockland County NY
