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Old 12-05-2019   #21
A26B
 
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Default Re: Careful with that camshaft

Quite awhile back, I purchased 31 LT5 engines the came out of a GM warehouse. Most of the engines were in some state of disassembly which included some loose cams with the sprocket still bolted to the cam. I put the cam in a vise clamping the hex end in the jaws to remove the sprocket/cam bolt. I didn't measure the twist in the camshaft, but it had to be in the 15~25deg range before I quit. Very spooky. After that, I would nest the camshaft in the cylinder head with the retainers & pin the cam with the timing pin. Works very well to remove/install the cam sprocket bolt.
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Old 12-05-2019   #22
LGAFF
 
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Default Re: Careful with that camshaft

Quote:
Originally Posted by Karl View Post
How many failed LT-5 camshafts have you come across?


I bought an engine from a guy in Georgia; one of the cams had a bad snout, and then I got a bunch of cams from Dave Generous from the Callaway program and several of those had broken snouts
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Old 12-15-2019   #23
WydGlydJim
 
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Default Re: Careful with that camshaft

I think I was told not sure by who, probably Jerry, to use the pins to hold the camshaft, instead of the rear hex head...I suppose theory is shortening up the distance reduces twist?
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Old 12-17-2019   #24
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Default Re: Careful with that camshaft

Quote:
Originally Posted by WydGlydJim View Post
I think I was told not sure by who, probably Jerry, to use the pins to hold the camshaft, instead of the rear hex head...I suppose theory is shortening up the distance reduces twist?
That will work for removal.
Will not work after you degree cam.
Sometimes pin hole does not align after degreeing the cam.

Pete
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Old 12-17-2019   #25
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Default Re: Careful with that camshaft

After having degreed the camshaft with the sprocket pin in place, I use the following process:
1) Ensuring that the sprocket pin is in place with the sprocket washer and the camshaft sprocket bolt nipped up to around 50ft lbs, check if the camshaft timing pin J37326 will fit through the cap into the cam.
2) If the timing pin does not align with the cam, rotate the crank very slightly until it does align. Insert the timing pin to positively hold the cam from rotating.
3) Remove the camshaft sprocket bolt, clean the threads in the cam with a solvent to remove any oil etc and fit a new camshaft sprocket bolt, applying oil to the bolt flange only plus Loctite 262 to bolt threads only. Torque to spec (factory replacement bolt 19ft lbs plus 80 - 85 degrees) or Jerrys Gaskets ARP bolt 10090566 to 80ft Lbs.
4) To be very safe, you can also use a 0.020" strip of cardboard to fit between one of the temporary camshaft retaining caps and the cam, in order to further prevent any slight movement of the cam.
5) Remove the timing pin (and 0.020" strip of cardboard if used) and re-check timing.
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Old 02-25-2021   #26
wfot
 
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Default Re: Careful with that camshaft

I figured I would share this that I figured out about the sprocket removal. I bought a disassembled engine and had the very same fear of holding the cam in a vise or the head an did not want to put any more stress anywhere that it did not have to be.

ironically, the cam chain is basically identical to every aftermarket ford motorsports 302/small block timing chain kit. from that ford motorsports kit I used the chain and crank gear. looped the FM/302 chain around the LT5 cam gear on one end and the FM/302 crank gear on the other end of the FM/302 chain put the whole set up into a vice and pinched the chain tight. looks like a figure 8. muscled the cam blot came right out with zero stress on the cam or the cam sprocket. Worked like a charm on all 4 cams. I ended up putting zip ties to help hold the chain around the crank gear.
it was a surprise to me that the chains were pitch but a good surprise

John
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Old 03-01-2021   #27
JThomas
 
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Default Re: Careful with that camshaft

Quote:
Originally Posted by Pete View Post
I use custom made aluminum temporary cam caps i install these on all the cam journals then use a breaker bar and box wrench to break cam bolt loose.
I have taken off 100's of LT5 cam bolts this way for 20 years with no issues.

I do not have any back history on this cam.
I have been buying and accumulating cams the past 20 years so at this time i can only speculate.
Maybe small crack that got worse with time or i'm just very strong.

What ever it was i have never seen this before.

Pete

PS
Regrind has nothing to do with this break i have 3 dozen regrinds out there running for years with no issues some with really hard racing time on them especially the ones in Al's,Bobs and my ZR-1's for the past 15+ years and these are the fastest N/A pump gas ZR-1's out there.
I'm going to go with you're "Very Strong"!
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Old 03-01-2021   #28
Pete
 
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Default Re: Careful with that camshaft

Quote:
Originally Posted by JThomas View Post
I'm going to go with you're "Very Strong"!
Ok we'll leave it at that 🤣🤣

Pete
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'91 #1635 PoloGreen 350 LT5
11.09 @ 129.27
11.04 @ 128.86
474RWHP 400RWTQ
http://www.youtube.com/watch?v=SFNFOhGGlR4
http://www.youtube.com/watch?v=ZlRIOMwaDYY
https://sites.google.com/site/peteszr1garage
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