Timimg Chain length?

[Chris McDade]

Im changing my high mileage timing chain. How do I measure to make sure I get the correct new chain. I don't want any slack in it when I install the new one.

Do I need to still run the tensioner if I get the correct length chain.

Thanks in advance.

 

[charlief1]

What chain do you want to run first. Double roller or single or stock. Specify which one you want first then we can help you better.

 

[Chris McDade]

Double Roller....Thanks

 

[bison]

I usually try a .004 under first and they are usually right on. I used a .006 under on the one i just assembled and it fit perfectly. I have not found a way to accurately determine the chain needed without trying one first. There are too many variables. Be sure the cam and crank gear are in the same plane.

 

[charlief1]

bison is 100% correct about having to try one and go from there. The only way to get closer is to measure between the center of the crank to the center of the cam and ask the manufacturer. It will give them a better idea of what you need but it's not an exact science unfortunatly.
BTW bison, where are you getting them from. Gonna be needing one soon it looks like.

 

[BADDGUY6]

Hope this helps.
http://romacusa.com/Sprocket_Data.pdf

 

[Nick Micale]

slack is your friend.....

........ I don't want any slack in it when I install the new one. Thanks in advance.

We use the method Bison suggested, too many variables.

My opinion, after a few hundred Buick timing chains, and a few that have failed, is the "tight" is not good. :frown:

The distance between crank and cam gets larger as the engine get to temperature.

 

[bison]

Hope this helps.
http://romacusa.com/Sprocket_Data.pdf

NIce but they still suggest having a standard chain as a baseline.

 

[bison]

We use the method Bison suggested, too many variables.

My opinion, after a few hundred Buick timing chains, and a few that have failed, is the "tight" is not good. :frown:

The distance between crank and cam gets larger as the engine get to temperature.

Ive seen a lot of engines where the sprockets arent lined up. Not a good thing. I always pull the crank forward and use a straight edge and feeler gauges to get it close. Ive seen variances in the crank and cam gears that required moving the cam gear back a little or shimming it outward a little. Not as easy with a non modular nose.

 

[Chris McDade]

Good info guys.

I had one that I pulled out of my parts laying around and there is slack on both sides. Not allot though. Im going to pull it off and see If I can get some numbers off of it.

Thanks

 

[Just a Six??]

Remember NO Tensioner with a double roller. I mentioned since you asked in your first post.

 

[Mad_Trbo]

Undersized Chains

Chris I have a couple of undersized never run chains from TA Performance. Using the method descirbed by Bison and Nick, I purchased several sets. If I have what you need, I would be willing to make you a deal.