Adjustung Valves
Race Director
Joined: Jun 2009
Posts: 10,428
Likes: 9
From: Southside of Western Norte Americano State of Confusion, ColoFornia
St. Jude '13
you know.. Im not sure about the F body.. but I would be checking the knock sensor and timing on this car.. what you are describing is preignition..pinging it sounds like a coffee can full of rocks being shaken.
Valve adjustment just isnt this hard. and if it isnt backfiring and missing they are probably very close.
Valve adjustment just isnt this hard. and if it isnt backfiring and missing they are probably very close.
Melting Slicks
Joined: Feb 2008
Posts: 3,286
Likes: 6
From: Palm Beach
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,009
From: Texas
Couple things...
If it's pinging, that is not the rocker arm adjustment. That is timing.
- Did you actually disconnect the ESC connector at the distributor and set the timing with a timing light or are you just winging it? Sounds like you're winging it. Even with too much advance, at idle the engine will sound fine and actually run quite smooth. Here's the danger....Too much advance and you could very well end up burning a valve.
- Do you know for a fact that the L98 springs have enough clearance to work with the stock cam and 1.6 rockers? With the added lift you risk experiencing coil bind. If the spring breaks and you drop a valve it won't be pretty.
If it's pinging, that is not the rocker arm adjustment. That is timing.
- Did you actually disconnect the ESC connector at the distributor and set the timing with a timing light or are you just winging it? Sounds like you're winging it. Even with too much advance, at idle the engine will sound fine and actually run quite smooth. Here's the danger....Too much advance and you could very well end up burning a valve.
- Do you know for a fact that the L98 springs have enough clearance to work with the stock cam and 1.6 rockers? With the added lift you risk experiencing coil bind. If the spring breaks and you drop a valve it won't be pretty.
Last edited by 96GS#007; Jun 22, 2010 at 11:44 PM.
Instructor
Joined: Oct 2009
Posts: 101
Likes: 0
From: Gilbert Az
This is also true with hydraulic lifters. If the preload is incorrect as load/rpm increases the lifter will absorb the preload adjustment that is not there thus loosing the lift and what some may be misconstrued as "pinging" may actually be rocker clatter because the lifter has absorbed the prelaod and is now too loose. Not always but at times. This can also go the other way on tight engines with high volume, high pressure pumps thus the need for anti pump up lifters so the oil pressure does not cause the lifter to push the valve open because of preload. I am a middle aged old fart that has been working on these engines for a while. Do not claim to know everything only what has worked for me and those I have done work for. Some times you just have to do things a little different.
Last edited by Killer408; Jun 23, 2010 at 02:22 PM. Reason: forgot a word
Thread Starter
Racer
Joined: Aug 2009
Posts: 496
Likes: 4
From: Cordova TN
Stock everything except for the rockers. I unplugged the est wire before I timed it.
Someone else has told me it sounds like coil bind. With 145k miles the springs could be weak since 1.6 is supposed to be fine with the stock cam and stock springs.
Thanks for all the replies. I will adjust them once again and maybe try my luck at replacing the springs.
I can now remove the valve covers in about 10 minutes so it isn't too difficult to go through them again.
Someone else has told me it sounds like coil bind. With 145k miles the springs could be weak since 1.6 is supposed to be fine with the stock cam and stock springs.
Thanks for all the replies. I will adjust them once again and maybe try my luck at replacing the springs.
I can now remove the valve covers in about 10 minutes so it isn't too difficult to go through them again.
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Racer
Joined: Mar 2010
Posts: 291
Likes: 1
From: Temecula Cali
It's not a mess at all if you use a little common sense. Use cardboard like in this video will make no mess at all. Just make sure the cardboard is down in the head so the oil will drain back to the motor. Get the motor up to operating temp and have at it. When the lifter quits tapping turn 1/2 turn more and tighten it down. Works great!
i noticed you had the alternator and all brackets on the car with the serp belt in full operation.
is there enough clearance to remove the valve cover without pulling the alt or the rear bracket? i was thinking i was going to have to yank the alt to get the valve cover off...
rob
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Great vid there (and even greater sound! wow!)
i noticed you had the alternator and all brackets on the car with the serp belt in full operation.
is there enough clearance to remove the valve cover without pulling the alt or the rear bracket? i was thinking i was going to have to yank the alt to get the valve cover off...
rob
i noticed you had the alternator and all brackets on the car with the serp belt in full operation.
is there enough clearance to remove the valve cover without pulling the alt or the rear bracket? i was thinking i was going to have to yank the alt to get the valve cover off...
rob
That was with open headers. Won't be doing that again! Melted the d&*n shifter cable. 
Racer
Joined: Mar 2010
Posts: 291
Likes: 1
From: Temecula Cali
gotcha - but you did have room to adjust the rockers with alt and bracket in place?
Thread Starter
Racer
Joined: Aug 2009
Posts: 496
Likes: 4
From: Cordova TN
OK I m back now with more info. I replaced the springs/seals on the driver's side of the engine and noticed that the roller tip is not the only thing touching. The self adjusting sides are hitting the top cover of the springs and getting nicked up pretty good especially on the exhaust rockers. Looks like I found what is causing the racket but what would cause the damage I am seeing? Pushrod length? From reading this forum and TGO I sure thought this would be a pretty straight forward swap but you live and learn.
Oh, the old springs were pretty worn out so changing them out was probably needed. Just replaced with stocked rated springs since I feel a little skiddish about going the mod route at this point. I am about ready to throw the 1.5 stamped back in and call it a day.
Thanks
I'll try to get around to posting some pics later today and show what I am seeing.
Oh, the old springs were pretty worn out so changing them out was probably needed. Just replaced with stocked rated springs since I feel a little skiddish about going the mod route at this point. I am about ready to throw the 1.5 stamped back in and call it a day.
Thanks
I'll try to get around to posting some pics later today and show what I am seeing.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
You can come out cheaper by selecting different valve spring retainers. Retainers that will give you the needed clearance.
What you're seeing is a fairly common problem with SA rocker arms used in performance applications; guys on all the other Forums complain about this clearance problem.
Jake
My son, Ryan M. Cameron, graduated from West Point on 22 May 2010! He was commissioned as a 2nd Lieutenant and I pinned on his first pair of "Butter Bars" PROUDEST DAY OF MY LIFE!!
What you're seeing is a fairly common problem with SA rocker arms used in performance applications; guys on all the other Forums complain about this clearance problem.
Jake
My son, Ryan M. Cameron, graduated from West Point on 22 May 2010! He was commissioned as a 2nd Lieutenant and I pinned on his first pair of "Butter Bars" PROUDEST DAY OF MY LIFE!!
Thread Starter
Racer
Joined: Aug 2009
Posts: 496
Likes: 4
From: Cordova TN
You can come out cheaper by selecting different valve spring retainers. Retainers that will give you the needed clearance.
What you're seeing is a fairly common problem with SA rocker arms used in performance applications; guys on all the other Forums complain about this clearance problem.
Jake
My son, Ryan M. Cameron, graduated from West Point on 22 May 2010! He was commissioned as a 2nd Lieutenant and I pinned on his first pair of "Butter Bars" PROUDEST DAY OF MY LIFE!!
What you're seeing is a fairly common problem with SA rocker arms used in performance applications; guys on all the other Forums complain about this clearance problem.
Jake
My son, Ryan M. Cameron, graduated from West Point on 22 May 2010! He was commissioned as a 2nd Lieutenant and I pinned on his first pair of "Butter Bars" PROUDEST DAY OF MY LIFE!!
or these
http://cgi.ebay.com/ebaymotors/sb-sb...item5d223cc95b
Last edited by megtom2; Jun 27, 2010 at 11:37 AM.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Did the stock heads have guide plates like the #113 in the Vette L98; if so did you remove them??
Did the stock motor come with self-aligning stamped steel rockers as do the Vette L98 with Al heads?
Did the stock motor come with self-aligning stamped steel rockers as do the Vette L98 with Al heads?
Thread Starter
Racer
Joined: Aug 2009
Posts: 496
Likes: 4
From: Cordova TN
q
I guess this has gone from being an adjusting valve lash thread to being a "Before you go roller rocker this is what you need to know" thread. lol
Last edited by megtom2; Jun 27, 2010 at 01:18 PM.