New timing chain, allowable slack?

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fshd4it

fshd4it

Squid inc
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New edelbrock timing chain, went on a lot easier than others I've done (which normally seem to be banjo string tight), just wondering if it may be a little too loose. I can just push a straightedge to the links with a 5/16 bolt in between it and the chain, and I get .030-.040" lash at the cam gear. I did this by hand, and measured with calipers, so I'll admit it's not exactly precise. This engine has been align honed, and I'm not sure if the shop didn't cheat and take a bit from the block. I also tried a new ProGear chain I have on hand and it was only marginally tighter. My FSM only gives maximum wear tolerances. Opinions, please?

20180226_082302.jpg
 
Did you replace sprockets and chain as a set? What engine / year?
 
Yep, all new. Motor is a '68 340. The sprockets don't look that great since the set's been sitting in the box on the shelf for quite a while, and whatever rust-preventative they used didn't work so well.
 
If the set is usa or European made, run the tensioner and don't lose any sleep over it.
 
I would install the tensioner P5007709. I have done so in my small blocks and it dramatically improved timing accuracy. All that slop causes the timing mark to jump around when you attempt to set it. I bet you have all seen this.
 
Check out a billet set, they are not that much, and fit real nice, and in mine experience very little stretch over time.
 
You had the block honed so that were the slop is from.
If you look at some catalogs they will offer you the correct set up.
Ted
 
The other set I tried is a billet ProGear/Avon one, and it was barely any better. That said, I put the exact same kind (ProGear, not Edelbrock) on my 360 the other day and it was a pretty tight fit, but I don't have any way to measure the distance between the crank and cam to compare the 2 motors with any precision. I figured the tensioner was an option, and even though it seems to have more supportes than haters, I don't want it to be considered a "bandaid" in this case. I know Cloyes makes .005" & .010" undersize timing sets, I figure I'd have to order one up and check fitment, then return it if it doesn't... but I haven't called them yet to see if they can recommend one from my rudimentary measurement.
 
DusTed74 said:
You had the block honed so that were the slop is from.
If you look at some catalogs they will offer you the correct set up.
Ted
Click to expand...
As I understand it, an align bore (done correctly) doesn't take any material from the block?
 
Only thing I don't like about tensioners is they wear. I have had two damage 2 engines (both Chevy with >100,000 miles on them) each time plastic fell into the timing chain and caused the chain to brake. One engine was a clearance motor, no harm no foul the other not so much.
 
dano said:
Are you degreeing the cam too?
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Eventually, yes. After finding the Lunati I put in my 360 was 8 degrees retarded when installed dot to dot, I'm a believer. Just not sure if the cam I have is the one I will run, however.
 
align hone can vary. bores too tight or too big or not aligned. so some material will be removed from block and caps-just like honing a cylinder-no other result possible. use a cloyes shorter set, my guess is .010"
 
I just got off the phone with a tech @ Cloyes, and with the way I described the fit I have now he suggested trying one of their stock size hand-matched billet units, as he thought the deflection I'm seeing in the chain wasn't excessive. If that's still too loose he said I could return it for an undersize one, and at least I'd be using one of their sets to check with. Apples to apples for comparison/measurement, not trying to figure a fit based on a different manufacturer's set.
 
fshd4it said:
Eventually, yes. After finding the Lunati I put in my 360 was 8 degrees retarded when installed dot to dot, I'm a believer. Just not sure if the cam I have is the one I will run, however.
Click to expand...

Good, and its not just the cam that can be off.

I run this:

Hughes Engines

and this:

Hughes Engines

But, have used Cloys (and Ford Motorsports, which is/was a Cloys) in many engines between my dad and I and the engines we've built for others with great success.
 
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