Timing Chain broke. What's a good replacement?

ttypewhite

Well-Known Member
Joined
Oct 1, 2001
Maybe i better get a camera and look inside to see if i can see a ding in the piston.
Now you're cooking with grease. Bigger question is how did it happen? During a pass? driving on the street? what rpm? This will tell you the severity of the hit, because there is no way that it didn't hit. This happened in my garage while my junk was warming up. Went in the house to get my wallet and heard a snap crackle pop. Damn near all my valves looked like this. Do yourself a favor and do it right, you will save a ton of money not going in the direction you just mentioned.

IMG_20211013_0953408.jpg
 

Haulz A

Active Member
Joined
Mar 31, 2015
Like TType white said- make sure no damage occurred to the engine which is almost impossible bc Ive broke two timing chains over the years. One driving about 15-20 mph and one racing the car at about 130 mph. The timing chain that broke driving slow did the most damage to the valve train- bent every valve in the cylinder head, the chain that broke at 130 mph only bent two intake and one exhaust valve.

At least do a leak down test with the rocker arms removed from the cylinder heads- I bet you will find at least three or more of those cylinders leaking air immediately. The bottom line- those cylinders heads will need a valve job. Call Ferrea Racing Components @ 1(888) 733-2505 or 1(954) 733-2505 and ask for Emanuel- they sell all the valve train components need to repair those cylinder heads or send those heads to Champion if you dont have a local machine shop to repair them. Good luck my friend.
 

turbo1962

Member
Joined
Jul 2, 2006
I did a leak down test today. putting 80 psi in cylinder and they are holding at 78 psi and 77 psi not any lower i also looked in the cylinders with a scope and could not find any damage . I already ordered a new roll master chain from TA performance.
 

Haulz A

Active Member
Joined
Mar 31, 2015
I did a leak down test today. putting 80 psi in cylinder and they are holding at 78 psi and 77 psi not any lower i also looked in the cylinders with a scope and could not find any damage . I already ordered a new roll master chain from TA performance.
Wow- I'm very surprised those cylinders held air without a major leak- like I said earlier, you gotta be one of the luckiest GN guys around if there's not any damage in the valve train.

After you replace the timing chain and remove the oil pan to check for any metal particle from the chain breakage- I would install the rocker arms and do a compression test prior to starting the engine. If the compression test is good and the engine runs fine- you need to go buy some lottery tickets before your luck runs out- Lol.
 

turbo1962

Member
Joined
Jul 2, 2006
Guess maybe i better buy some lottery tickets . I have been doing some research on timing chain breaking, They say sometimes if the cam stops in the right spot no valves would hit. Thanks everyone for your help.
 

Haulz A

Active Member
Joined
Mar 31, 2015
Guess maybe i better buy some lottery tickets . I have been doing some research on timing chain breaking, They say sometimes if the cam stops in the right spot no valves would hit. Thanks everyone for your help.
Make sure when you remove the front cover- inspect cam tensioner . It should be a comp cam PN# 249-269 steel roller bearing assembly with shims- not the stock spring style tensioner bc you have a roller camshaft according to your threads posted.

You will have to shim the roller button to acquire approximately .005 to .008 camshaft end play. Also the crankshaft should be somewhere in that range as well. Also verify the springs on the cylinder heads have correct seat/open pressure recommended for the camshaft at the boost level you plan on running as well to prevent valve float.

Attention to detail during the repair process in those areas will net you a higher success rate my friend.
 
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