Solid Roller Cam Button Flexing Timing Chain Cover
Thread Starter
Safety Car
Joined: Apr 2001
Posts: 3,525
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From: Houston TX
Solid Roller Cam Button Flexing Timing Chain Cover
I have an L-98 block that is running a hi-volume oil pump (read as high force to push the cam forward and retard timing) and a slightly radical solid roller cam. The cam button was installed with the proper amount of clearance, but I believe that I feel is loosing advance under load (I can adjust the timing to 50+ degrees w/o a hint of detonation under boost). I hear from machinists that the stock timing cover has a tendency to flex when used with a SR cam and a HV oil pump. Does anyone manufacture either an aluminum cover (2 pc or 3 pc OK) for the L-98 or a reverse rotation water pump that has the cam stop "jack bolt" built in? If not, I am going to be forced to weld a tab on a new water pump to install a cam button stop bolt.
I can not be the first one to encounter this situation.
Thoughts?
Aaron
I can not be the first one to encounter this situation.
Thoughts?
Aaron
Drifting
Joined: Feb 2002
Posts: 1,952
Likes: 2
From: Little Rock Arkansas
Re: Solid Roller Cam Button Flexing Timing Chain Cover (AKS Racing)
This IS a very common problem with the sheet metal timing covers and HV oil pumps when not using an original roller block with a retainer plate. Edelbrock's Victor series water pump for the Vettes is reverse drive and has the cam thrust stud; or Comp, Milodon, Moroso, and a couple others build solid single, two, and three piece timing covers. I actually have an Edelbrock pump I'd sell you; it's still in the box (dyno time only). IM me if you're interested in the pump.
-Jeb
-Jeb
Thread Starter
Safety Car
Joined: Apr 2001
Posts: 3,525
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From: Houston TX
Re: Solid Roller Cam Button Flexing Timing Chain Cover (jburnett)
Jeb,
Thanks for the reply. I thought no one would reply. Some seem to get lost in the more technical issues.
I am using an original roller block, but was advised by both my machinist and tech from Comp Cams to have the cam machined with the large bolt circle on the front of the cam due to the high lift and high spring psi (there have been instances where the bolts were sheared under extreme situations). I currently run a cam button, and was today advised by CC to move to their aluminum timing chain cover (2 pc or 3 pc, either will work).
As a side note, I have been chewing through distributor gears. I think this is a result of the cam walking forward. I think that I am loosing 15+ degrees of timing under full load.
Aaron
Thanks for the reply. I thought no one would reply. Some seem to get lost in the more technical issues.
I am using an original roller block, but was advised by both my machinist and tech from Comp Cams to have the cam machined with the large bolt circle on the front of the cam due to the high lift and high spring psi (there have been instances where the bolts were sheared under extreme situations). I currently run a cam button, and was today advised by CC to move to their aluminum timing chain cover (2 pc or 3 pc, either will work).
As a side note, I have been chewing through distributor gears. I think this is a result of the cam walking forward. I think that I am loosing 15+ degrees of timing under full load.
Aaron
Drifting
Joined: Jul 2001
Posts: 1,897
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From: La Fontaine Indiana
Re: Solid Roller Cam Button Flexing Timing Chain Cover (AKS Racing)
Aaron when I built my engine I used a cast aluminum cover it has a plate that can be removed to change the cam timing. I have a torrington bearing behind the gear serves as a thrust plate. The timing cove has a bearing on an adjustable bolt to set cam play. The cover is heavy won't flex but I had to modify the water pump to get it on. Dam this is things that I had forgot all about. The stock pump has a bulge on the back remove that plate make one from a flat plate grind about a third of the head off of the cap screws that hold it on and install. Mine has been trouble free for more than four years. I was doing some tuning today and I was watching the timing and data logging several other things my timing is stable. I think you are correct in what your problem is.
Thread Starter
Safety Car
Joined: Apr 2001
Posts: 3,525
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From: Houston TX
Re: Solid Roller Cam Button Flexing Timing Chain Cover (black bart)
Black Bart,
Who manufactures the cover of which you speak? The aluminum cover that I am looking at is made by Comp and relies upon a bearing cam button on the frontside. I would be interested in a cover with an adjustable cam button stop, which I believe you have described.
As a side note, the Hydraulic roller you run required this set-up, or was this an extra effort on your part? I had no choice with mine as mine is a large bolt circle solid roller.
Thanks,
Aaron
Who manufactures the cover of which you speak? The aluminum cover that I am looking at is made by Comp and relies upon a bearing cam button on the frontside. I would be interested in a cover with an adjustable cam button stop, which I believe you have described.
As a side note, the Hydraulic roller you run required this set-up, or was this an extra effort on your part? I had no choice with mine as mine is a large bolt circle solid roller.
Thanks,
Aaron
Drifting
Joined: Jul 2001
Posts: 1,897
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From: La Fontaine Indiana
Re: Solid Roller Cam Button Flexing Timing Chain Cover (AKS Racing)
Aaron Sorry about the slow response but I have been really busy today and I had to dig through all my old invoices to find out what it was.
I bought it on Jan. 25,2000 from Summit I think it is made by cloyes because the Summit part is CLO-9-221 My current catalog don't show it but I went to the Summit web site and typed that number and it came up price is $95
The site shows a picture of it but not a very good one. Caution most if not all high output water pumps will not work with this cover but when you put a flat plate on and do away with the bulge on the stock pump it will flow alot more water. Hope this works for you. I got to go check my blower I think I may have an oil seal leaking on it :mad How some reason I'm getting bad detonation may be oil causing it. :cry
I bought it on Jan. 25,2000 from Summit I think it is made by cloyes because the Summit part is CLO-9-221 My current catalog don't show it but I went to the Summit web site and typed that number and it came up price is $95
The site shows a picture of it but not a very good one. Caution most if not all high output water pumps will not work with this cover but when you put a flat plate on and do away with the bulge on the stock pump it will flow alot more water. Hope this works for you. I got to go check my blower I think I may have an oil seal leaking on it :mad How some reason I'm getting bad detonation may be oil causing it. :cry
