My ongoing engine rebuild nightmare
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
I did the torrington bearing behind the cam gears, roller bearing button, and the chain oiling mod on the left-most oil galley plug, and the AllStar polished aluminum timing cover; it all tucks behind a corvette-style water pump PERFECTLY. -The AllStar cover wants a THICK oil pan gasket so only go that route if you have an oil pan that requires the thick gasket.
-The drill bit for the oiling mod is just so insanely small I had to wrap it in a bit of duct tape to get the drill to even grab it; it was some kinda miracle that the drill bit didn't break. I did it to a press-in plug, I have NO IDEA how you'd successfully drill a hole that small into the thick screw in plugs...
Adam
-The drill bit for the oiling mod is just so insanely small I had to wrap it in a bit of duct tape to get the drill to even grab it; it was some kinda miracle that the drill bit didn't break. I did it to a press-in plug, I have NO IDEA how you'd successfully drill a hole that small into the thick screw in plugs...
Adam
Melting Slicks
Joined: Jun 2016
Posts: 2,979
Likes: 332
From: Woodinville WA
I think he mentioned that it was VERY hard not to break those teeny tiny drill bits and to use a drill press or just have machine shop do it.
I used the blue and white paper Felpro gasket for the timing chain cover, but added a bead of RTV because I was afraid of oil slowly seeping through the paper gasket without it after doing the drill press mod. I've only primed with a distributor turned priming tool, but not a single drip of oil while priming for a good long while, anyway.
Adam
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Team Owner
Joined: Jan 2006
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From: Into the Mystic And yet, despite the look on my face, you're still talking TN
St. Jude Donor '09 thru '25
I'm going to call Lunati's tech line this morning. They were very helpful with the lifters. See what they recommend about buttons and chains. Then I'm going to the shop and give him a chance to refund at least part of my money. I just don't trust them to fix it correctly.
Burning Brakes
Joined: Feb 2005
Posts: 894
Likes: 91
You really don't need "cam buttons" any longer if you prep the block beforehand, you just use a later style thrust-plate and a later stepped-nose cam!
Been doing these for a few years now, no end-play checking, no buttons, any timing cover works!!
Thanks, Gary in N.Y.
P.S. We developed this method of setting up all the early SB's, and haven't used any buttons in long time now. Here's a link to some reading to explain how we did it (https://www.chevelles.com/forums/18-...rly-block.html).
Been doing these for a few years now, no end-play checking, no buttons, any timing cover works!!
Thanks, Gary in N.Y.
P.S. We developed this method of setting up all the early SB's, and haven't used any buttons in long time now. Here's a link to some reading to explain how we did it (https://www.chevelles.com/forums/18-...rly-block.html).
Thread Starter
Team Owner
Joined: Jan 2006
Posts: 39,379
Likes: 171
From: Into the Mystic And yet, despite the look on my face, you're still talking TN
St. Jude Donor '09 thru '25
You really don't need "cam buttons" any longer if you prep the block beforehand, you just use a later style thrust-plate and a later stepped-nose cam!
Been doing these for a few years now, no end-play checking, no buttons, any timing cover works!!
Thanks, Gary in N.Y.
P.S. We developed this method of setting up all the early SB's, and haven't used any buttons in long time now. Here's a link to some reading to explain how we did it (https://www.chevelles.com/forums/18-...rly-block.html).
Been doing these for a few years now, no end-play checking, no buttons, any timing cover works!!
Thanks, Gary in N.Y.
P.S. We developed this method of setting up all the early SB's, and haven't used any buttons in long time now. Here's a link to some reading to explain how we did it (https://www.chevelles.com/forums/18-...rly-block.html).
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
Pretty sure the cam walking issue is related to that roller timing chain. I agree 100% with gkull and have personal experience as well: There is no way a roller cam can walk forward in a SBC C3 with stout quality durable double roller timing chain...no chance....The chain is too tight and too strong.
I went through the hocus pocus about the roller cam, cam button, and cam walking hysteria back in 2014 during my rebuild of the 355 L-82 with a howards roller cam. After extensive personal reading on the subject, advice from knowledgeable car gurus who have actually used retro rollers in a SBC for a C3, and personal advice from my expert builder who did the short block build for me on the 355 L-82, i surmised the following which has been validated 6 years later with a perfectly operating L-82 355 roller cammed motor:
1. The GM OEM timing Chain cover will supposedly flex with a roller cam and cam button behind it pushing on the cover. Not in a SBC C3 where the cover sits directly against the back of the water pump which further reinforces the all ready heavy gauge metal cover....chance of flexing? None
2. The roller cam requires a cam button to prevent the cam from walking forward.....Nope...See my opening comment. A quality double roller timing chain will NOT flex, stretch or bend, allowing the cam to walk forward.
3. Using a cam button, which I did use for insurance, requires trial and error to get the clearance correct? Nope. Just slightly dimple the timing chain cover for a nylon cam button to fit snuggly and done.
4. Measuring the pushrods for proper fit also was completely overly complicated by many, and it too, is a clear procedure, and easy.
All told much of the roller cam install is very overblown and is moderately easy.....
I went through the hocus pocus about the roller cam, cam button, and cam walking hysteria back in 2014 during my rebuild of the 355 L-82 with a howards roller cam. After extensive personal reading on the subject, advice from knowledgeable car gurus who have actually used retro rollers in a SBC for a C3, and personal advice from my expert builder who did the short block build for me on the 355 L-82, i surmised the following which has been validated 6 years later with a perfectly operating L-82 355 roller cammed motor:
1. The GM OEM timing Chain cover will supposedly flex with a roller cam and cam button behind it pushing on the cover. Not in a SBC C3 where the cover sits directly against the back of the water pump which further reinforces the all ready heavy gauge metal cover....chance of flexing? None
2. The roller cam requires a cam button to prevent the cam from walking forward.....Nope...See my opening comment. A quality double roller timing chain will NOT flex, stretch or bend, allowing the cam to walk forward.
3. Using a cam button, which I did use for insurance, requires trial and error to get the clearance correct? Nope. Just slightly dimple the timing chain cover for a nylon cam button to fit snuggly and done.
4. Measuring the pushrods for proper fit also was completely overly complicated by many, and it too, is a clear procedure, and easy.
All told much of the roller cam install is very overblown and is moderately easy.....
used a double roller cloys timing chain set up.
timing cover DOES NOT touch the back of water pump. I had to add metal to the outside of the timing cover to make that happen.
needed the button plus a dimple plus metal on timing cover to get it to stop walking forward.
when the cam walks forward, so does the distributor drive gear and that WILL cause problems.
so ya, cam walk can be an issue. Most blocks maybe not some however, definitely yes!
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
The "double roller" chain you posted a pic of is not a True Roller chain........you need the True Street Roller Cloyes 9-1100. It has actual rollers on each link....the cheap ones do not and wear out quickly.
I ALWAYS use a button on a roller cam.......on a SBC....use the Comp short button, and the Allstar Steel Cad plated cover: https://allstarperformance.com/sbc-t...over-all90010/
This setup requires zero endplay check.......it is right on the money and the Fel Pro timing cover gasket is your .010 endplay. If you don't believe me.....try it, I stumbled across it in 2006.
Why a button? It is not there to hold anything all of the time....but if you get in a high RPM overrev situation under a load.....the cam will walk.....this side loads the rollers on the lifters, not good.
Jebby
I ALWAYS use a button on a roller cam.......on a SBC....use the Comp short button, and the Allstar Steel Cad plated cover: https://allstarperformance.com/sbc-t...over-all90010/
This setup requires zero endplay check.......it is right on the money and the Fel Pro timing cover gasket is your .010 endplay. If you don't believe me.....try it, I stumbled across it in 2006.
Why a button? It is not there to hold anything all of the time....but if you get in a high RPM overrev situation under a load.....the cam will walk.....this side loads the rollers on the lifters, not good.
Jebby
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Thread Starter
Team Owner
Joined: Jan 2006
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From: Into the Mystic And yet, despite the look on my face, you're still talking TN
St. Jude Donor '09 thru '25
I talked to Lunati and he said "They didn't use a cam button?" Got the part numbers for the button, locking plate and timing chain.
Jebby....I did not think that was a true roller chain. Forgive my ignorance but if I replace the timing cover, how do I correctly relocate the timing pointer?
Jebby....I did not think that was a true roller chain. Forgive my ignorance but if I replace the timing cover, how do I correctly relocate the timing pointer?
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
I talked to Lunati and he said "They didn't use a cam button?" Got the part numbers for the button, locking plate and timing chain.
Jebby....I did not think that was a true roller chain. Forgive my ignorance but if I replace the timing cover, how do I correctly relocate the timing pointer?
Jebby....I did not think that was a true roller chain. Forgive my ignorance but if I replace the timing cover, how do I correctly relocate the timing pointer?
Jebby
Thread Starter
Team Owner
Joined: Jan 2006
Posts: 39,379
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From: Into the Mystic And yet, despite the look on my face, you're still talking TN
St. Jude Donor '09 thru '25
Pro
Joined: Mar 2014
Posts: 529
Likes: 113
From: Texas
I talked to Lunati and he said "They didn't use a cam button?" Got the part numbers for the button, locking plate and timing chain.
Jebby....I did not think that was a true roller chain. Forgive my ignorance but if I replace the timing cover, how do I correctly relocate the timing pointer?
Jebby....I did not think that was a true roller chain. Forgive my ignorance but if I replace the timing cover, how do I correctly relocate the timing pointer?
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Jebby
Thread Starter
Team Owner
Joined: Jan 2006
Posts: 39,379
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From: Into the Mystic And yet, despite the look on my face, you're still talking TN
St. Jude Donor '09 thru '25
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
The "double roller" chain you posted a pic of is not a True Roller chain........you need the True Street Roller Cloyes 9-1100. It has actual rollers on each link....the cheap ones do not and wear out quickly.
I ALWAYS use a button on a roller cam.......on a SBC....use the Comp short button, and the Allstar Steel Cad plated cover: https://allstarperformance.com/sbc-t...over-all90010/
This setup requires zero endplay check.......it is right on the money and the Fel Pro timing cover gasket is your .010 endplay. If you don't believe me.....try it, I stumbled across it in 2006.
Why a button? It is not there to hold anything all of the time....but if you get in a high RPM overrev situation under a load.....the cam will walk.....this side loads the rollers on the lifters, not good.
Jebby
I ALWAYS use a button on a roller cam.......on a SBC....use the Comp short button, and the Allstar Steel Cad plated cover: https://allstarperformance.com/sbc-t...over-all90010/
This setup requires zero endplay check.......it is right on the money and the Fel Pro timing cover gasket is your .010 endplay. If you don't believe me.....try it, I stumbled across it in 2006.
Why a button? It is not there to hold anything all of the time....but if you get in a high RPM overrev situation under a load.....the cam will walk.....this side loads the rollers on the lifters, not good.
Jebby
Since these few mods it has been trouble free.
Burning Brakes
Joined: Feb 2014
Posts: 1,045
Likes: 226
From: Cape Neddick Maine
2020 C3 of the Year Finalist - Modified
I run a retro roller cam. I have a Torrington thrust bearing against the block as Gkull suggests. Years ago I had a timing gear actually chewing away at the front of the block. When I built my SBC i went back and forth about using a cam button. some times you don't need it some times you do. So I erred on the side of caution and put one in along with a heavier front cover and added steel to the inside just piece of mind.
Hope this helps.
Hope this helps.
Burning Brakes
Joined: Jun 2020
Posts: 881
Likes: 113
Regardless of chain type/quality:
If it's a retro-fit roller in a pre-roller block, you should install a correctly-clearanced cam button.
On OE roller blocks, GM had the wisdom to design a stepped relief on cam nose; with a corresponding retainer bolted to front of block as well.
Seems Gosfast retro-fit solution emulates OE GM design.
If it's a retro-fit roller in a pre-roller block, you should install a correctly-clearanced cam button.
On OE roller blocks, GM had the wisdom to design a stepped relief on cam nose; with a corresponding retainer bolted to front of block as well.
Seems Gosfast retro-fit solution emulates OE GM design.
Le Mans Master
Joined: Oct 2007
Posts: 7,446
Likes: 972
From: Tennessee/Rhode Island
Like I said earlier, use a cam button for insurance by slightly dimpling the timing cover and install cam button..no elaborate measuring needed or required. Water pump sits directly against timing chain cover..................no reinforcement needed on a C3.
Burning Brakes
Joined: Jun 2020
Posts: 881
Likes: 113
many aftermarket waterpumps have an extra threaded boss/lug at bottom of pump; its sole purpose is for install of simple adjustable bolt/stud to press against timing cover at where cam button contacts cover. Especially for those that get run hard, proper button-to-cover clearance does matter. In similar manner as OE roller block cam retainer does. YMMV
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
which timing cover does this? Link? Like I said, mine does not. It’s so close that a metal ruler won’t even fit in the space so the adjustable nut cover is out, but it’s enough to allow the cover to flex and cam to walk.