How tight is correct for the timing chain?

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LovetheA's

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Im in the process of reinstalling my cam after having it notched for better oiling. When I pulled off my timing chain it had a little slack in it. Is some amount of slack ok in a double roller timing chain? If so how much? Also is it good insurance to just put another double roller chain in when doing install of the cam?
Carl
 
Book says 1/2 of play, but with any kind of performance engine, less is better.
 
I hope you didn't put the chain on with the dots lined up like in the photo.
 
Buy a better timing chain ,at least a Edelbrock True Roller. Better yet : look for a "Rolan supplied " chain. The 39.99 " Cloyes ," ,will be a disappointment ,into your performance future..
Been there ,done that
Spend the money man. .
 
72Dart6pack
I thought if the dots are lined up the engine is at TDC? Isn’t that how you want to take apart and reassemble the chain and how to set the cam when reinstalling so that timing is on Point? I haven’t pulled the chain off yet. Now I’m worried I’m doing something wrong. Please alaborate?
Carl
 
TDC on #6 if lined up like in the photo. Easier to get that part right if you do it that way. Lined up in the middle you will have to pull the distributor and turn the rotor a half turn and re-install. (re-time of course)
 
I thought for a 383 TDC should be cylinder #1( front drivers side)? Then just reinstall the distributor with the rotor pointing in the same direction which I have marked with sharpie making sure it is on the correct stroke not off 180?
 
Your good just turn the crank 1 turn after you put it back together and it will be on #1 TDC
 
I think I understand everyone. As it sits it is TDC on compression stroke on #6. If moved one rotation of crank than the gears move one revolution and it moves to TDC #1 on compression stroke and dots line up again. Have I got it correct?
 
LovetheA's said:
I think I understand everyone. As it sits it is TDC on compression stroke on #6. If moved one rotation of crank than the gears move one revolution and it moves to TDC #1 on compression stroke and dots line up again. Have I got it correct?
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Correct. One rotation and the dots will still be lined up but not next to each other.
 
You SHOULD have degreed the cam in rather than do the dot to dot deal.

You now have no idea where the cam is timed, unless you did degree the cam and the dots actually lined up.
 
Install a chain tensioner from a magnum and don't worry about it.

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The tighter your timing chain the better you cam timing and timing. Not a place to skimp in my mind.......
 
Okay I probably should include some additional info to better explain the situation. It is a big block 383 B engine. The engine was built about 15 years ago but only has about 12,000 miles on it. At that time the cam was degreed. Keep in mind I’m learning a lot of this as I go along so excuse my ignorance on some things. That’s why I ask so many questions and youtube instructional videos have become my friend. Before I broke it down it ran great dynoed at 340 rwhp with stock 915 heads, approx 9.8 to 1 compression, basic Keith black HP Pistons, Harland sharp roller rockers etc. I decided to do some upgrades on the engine. Move up to edelbrock performer rpm heads and buy a geometry kit for the rockers from B3 racing engines. Long story short one thing leads to another when you tear into an engine and while it’s apart for durability I wanted to try and freshen up whatever I could that wasnt crazy expensive. I’m hoping to be able to take out the cam and get it notched for better oiling to work with the new heads and reinstalled rockers. What I don’t want to do is mess anything up but instead pull out cam, pull out distributor and gear drive, fuel pump and then reinstall everything as before. I though if the timing was set on TDC correctly then I can just time it and have a great running engine. So I thought I had lined up my timing by looking at the gears for the crank and cam at TDC based on the markings. I would take everything apart carefully marking everything and reassemble no problem easy peezy. But now I’m totally confused and don’t know what I did wrong? If I rotate the engine one revolution at the crank then it moves a piston up and down twice. Either on the compression stroke or power stroke. Am I on the power stroke and should be on the compression stroke therefore I have to move the crank one revolution? If I do that wont the gears move around once and then the dots should line up again and be close together as long as the cam was degreed when first assembled? I can then remove everything and put it back the same, making sure the distributor points to the correct piston? Then my rotor on my distributor should point to cylinder #1 at the top of compression stroke where now it is pointing to cylinder #6 at the top of the power stroke. Did I get it? Sorry I don’t mean to be so rudimentary in my understanding this is my first engine tear down.
 
The camshaft is an older mopar performance camshaft. I believe .484 lift 284deg duration. Is it possible that the two dots on the gear drives shouldn’t be close to each other. More like cam gear at 12 o’clock and crank gear at 12 o’clock? How do I know? I always thought that the cam gear should be at 6 o’clock and crank gear at 12 o’clock. Now I’m overthinking this.
 
There's no manual that I know of that's ever printed that dot to dot is 180* out. You can do one of two things. Get a 12" ruler and line the cam gear up at 12 o'clock and crank gear at 12 o'clock, OR simply line the dots up together and drop the distributor in at #6. The latter is what I do.......AFTER of course degreeing the cam. If you are replacing the timing set, the camshaft will have to be degreed again. As stated, if you want stable cam timing for a long time, don't skimp. A timing set under 100 dollars is skimping. I like the Comp billet sets. The last one I bought was 110 dollars and it was for a big Chevy. If you do decide to skimp on the timing set, advance the cam even a few extra degrees ahead of where the cam card says, because it will be stretch after 5 minutes of run time.
 
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When the crank is turned 1 revolution the cam turns 1/2 revolution. That puts both timing dots at 12 oclock.
The piston goes down and up 1 time.
 
By this I assume you had a notch ground across the cam journal oil holes. A lot of oil already goes up to the rocker shafts through the stock holes. Updating that old cam grind would have been a nice investment to take advantage of the increased head flow.

One of the best "tricks" I found regarding timing chains is to soak them on their side in fresh, warm high quality synthetic gear oil for a few days before installing them. You can tap the container a few times a day and see small bubbles coming out of the rollers as it fills them up.

I stumbled on this after running out of chainsaw bar oil one time and substituted some Redline 140w synthetic gear oil. The stuff immediately made my chains last 6 to 8 times as long, virtually eliminated chain adjustments during the life of the chains and is not that much more expensive.

I've done this on half a dozen engine builds so far, and it has pretty much eliminated any chain stretch I used to get. Buy the best timing set you can afford and soak that chain. I'll never install another chain without doing it. It just works.
 
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