Reusing stretched timing set....?

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MopaR&D

MopaR&D

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I pulled apart the front of the 318 in my '88 Fifth Ave to replace the stock chain and sprockets as preventative maintenance (would post on the FMJ forum but way more engine experts here). I wanted to reuse the double-roller timing set I pulled off my busted 360 (broken piston ring land) with about 25k miles on it. It does have quite a bit of slack, close to 3/4" which I have read is supposed to only be 1/2". Thing is this car is strictly a driver/cruiser and I don't want to spend any more than I need to; I already bought a new OEM replacement harmonic balancer for $80 because the old one had badly deteriorated rubber and IF I do get a new timing set I'm going for one of the better-quality ones which run around $150... Keep in mind I bought this car for $700 lol.

My idea is to also swap over the timing chain tensioner I had on that 360 to keep the chain from bouncing around, set the crank sprocket keyway to give +4 degrees of advance to make up for the slack in the worn timing set and call it good. What do you guys think? The engine is all stock internally including the cam, I am converting from 2-bbl Lean-Burn setup to a ThermoQuad on a Performer intake but even then it'll barely rev over 4500 RPM with the stock cam.
 
Khalid: Buy a fresh chain, use your timing tensioner..be done with it... Retarded camshaft timing , will kill torque here.... JMHO...
 
Abodybomber said:
Khalid: Buy a fresh chain, use your timing tensioner..be done with it... Retarded camshaft timing , will kill torque here.... JMHO...
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That's why I'm thinking of installing the crank sprocket with 4* advance to make up for the slack... If this was a performance engine I would totally go with new everything but I feel like unless the chain is going to stretch even more a significant amount or break something, it will be good enough....???

I'd also much rather not have to wait an additional 3-5 days to get this thing back on the road, it's already all apart.

Then there's the fact that basically all new timing sets get loose over time anyway, the better ones just don't loosen as much as quickly as the cheap ones.
 
MOPEkidD-3 said:
That's why I'm thinking of installing the crank sprocket with 4* advance to make up for the slack... If this was a performance engine I would totally go with new everything but I feel like unless the chain is going to stretch even more a significant amount or break something, it will be good enough....???

I'd also much rather not have to wait an additional 3-5 days to get this thing back on the road, it's already all apart.

Then there's the fact that basically all new timing sets get loose over time anyway, the better ones just don't loosen as much as quickly as the cheap ones.
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True.... You could advance it four degrees, and throw the the tensioner in it, that would be better than nothing, Khalid....
 
Abodybomber said:
True.... You could advance it four degrees, and throw the the tensioner in it, that would be better than nothing, Khalid....
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Tim, I know it would be the "right" thing to do with all new parts but yeah... basically just want something that won't break apart and jump the chain like the factory nylon silent-chain setup. I had that happen on the 318 in my Duster a few months after I first got it, MAN that pi**ed me off lol. Nothing like stepping on the gas and hearing that awful sputter-clunk sound, then silence... followed by cranking that sounds like I lost all compression.
 
MOPEkidD-3 said:
Tim, I know it would be the "right" thing to do with all new parts but yeah... basically just want something that won't break apart and jump the chain like the factory nylon silent-chain setup. I had that happen on the 318 in my Duster a few months after I first got it, MAN that pi**ed me off lol. Nothing like stepping on the gas and hearing that awful sputter-clunk sound, then silence... followed by cranking that sounds like I lost all compression.
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Yes, I know that sound......(sigh)....
 
3/4 slack though not optimum isn't enough to matter in an inexpensive just make it ok driver, and it sure isn't enough to warrant advancing it.
I say throw it in stock and run it, or advance it just for the fun of it if you want.

Oh yea, just my opinion. :D
 
TrailBeast said:
3/4 slack though not optimum isn't enough to matter in an inexpensive just make it ok driver, and it sure isn't enough to warrant advancing it.
I say throw it in stock and run it, or advance it just for the fun of it if you want.

Oh yea, just my opinion. :D
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That brings up the question, about how many degrees of timing retard would that much slack equal? My timing set only does +/- 4 degrees or zero, nothing in between...
 
I did just what you are thinking with my 318 truck.Got the engine for free(unknown mileage) got matched used steel gears and chain. Only thing I didn't do was the tensioner and boy I wish I did. Kinda noisey when cold but fine after warm up. Been running for 5 years now.Same as you just a driver.Almost has 30K since now.
 
MOPEkidD-3 said:
That brings up the question, about how many degrees of timing retard would that much slack equal? My timing set only does +/- 4 degrees or zero, nothing in between...
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Don't know for sure but it aint anywhere near four.
Go ahead and do four just for the fun of it, as it won't hurt anything.
I was just making the point that I didn't think it was necessary for it to run decent on a budget.
 
TrailBeast said:
Don't know for sure but it aint anywhere near four.
Go ahead and do four just for the fun of it, as it won't hurt anything.
I was just making the point that I didn't think it was necessary for it to run decent on a budget.
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I just slid the sprockets on straight-up... you think I should try 4* advance? Will it make a noticeable difference? It had lots of grunt before and got decent MPGs with the stock silent chain, that thing had about 1" of slack.
 
MOPEkidD-3 said:
It had lots of grunt before and got decent MPGs with the stock silent chain, that thing had about 1" of slack.
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Yea, that was my point.:D
Straight up/4 degrees, whatever as you won't feel any difference anyway.
About the only difference it will make is to move the torque band higher in the RPM's.
It'll leave a light with an automatic better straight up.

I'm not an expert on cams by any means, just so you know. :D
 
So you're trying to decide if you should reuse the 360 piece you have or buy a new, top of the line race piece??? That's quite the swing. What you paid for the car doesn't compute here. You're there now - spend the $$ and replace it. Think of it this way, if that 360 chain fails on you - how much did saving that buck fifty just cost you? And I'm not saying you can't reuse the 360 piece, I just believe that one should go with new if the opportunity presents itself.
 
This topic is getting a bit long and loose too... :)

Put a degree wheel on the crank with the old chain attached. Turn crank back and forth and measure degrees of slack.
I recall those 4 degrees on the sprocket are usually crank-degrees. Which means the cam only sees 2 degrees change.
And yes you can sure feel the difference, but it depends on your personal inbuilt ability to sense technical improvements, or not.

Even though I never want to see any play in a timing chain, I would run it, especially with the chain-tensioner.

Even if the old chainset has 2 degrees of retard, I would install it in the 4deg advance way and have 2 degrees to 'wear' in the future as spare :)
A too far advanced cam will build more cylinder pressure (and torque) but might run out of steam above 3-4k rpm.
Beware of pinging though.
 
You can buy a new double roller set from advance auto for around $30.00ish. Thats is what i would do.
 
gliderider06 said:
You can buy a new double roller set from advance auto for around $30.00ish. Thats is what i would do.
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They slack out as much in the first 1000 miles. Under the circumstances, I give my thumbs up on re using the 360s chain , but I'd degree it. We're just prolonging the life of junk, not a race engine.
 
MOPAROFFICIAL said:
They slack out as much in the first 1000 miles. Under the circumstances, I give my thumbs up on re using the 360s chain , but I'd degree it. We're just prolonging the life of junk, not a race engine.
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Agreed.
If you have it laying around anyway, what else are you going to use it on? This is why you save decent/okay used parts.
I would install it maybe the 4 degrees advanced and forget about it.
It's just a thrown together thing anyway, and you have the tensioner to boot.
Don't over think this, it'll be a lot better than what you had, and will last trouble free for a long time..........
I'm all about using GOOD used parts if you are on a budget, that's how i built my Dart Sport, and is the reason i am driving it instead of still building it!
It ain't going to blow up if you do this!
 
Dartnut said:
Agreed.
If you have it laying around anyway, what else are you going to use it on? This is why you save decent/okay used parts.
I would install it maybe the 4 degrees advanced and forget about it.
It's just a thrown together thing anyway, and you have the tensioner to boot.
Don't over think this, it'll be a lot better than what you had, and will last trouble free for a long time..........
I'm all about using GOOD used parts if you are on a budget, that's how i built my Dart Sport, and is the reason i am driving it instead of still building it!
It ain't going to blow up if you do this!
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That's exactly my thinking with this. I could have thrown away the timing set, rods, crank, etc. because I wouldn't call them "perfect", but I decided to save them because I like having spare parts; I've been in the hobby about 10 years and could definitely use a bigger stash to select from. My Fifth Ave ran well enough to not even bother with the stock timing set but I decided to at least replace it with something that doesn't have 1" of slack and plastic cam sprocket teeth at the same time I do my 4-barrel conversion. I will surely be revving it higher than before (meaning 4200-ish instead of 3500) and probably just driving it harder in general at times just to have fun but this is a 4000-lb cruiser with A/C and power everything, strictly street driver duty.

I didn't want to take the time to check the play with a degree wheel but I did slide on the crank sprocket with the 4* advance keyway and noted the position of the timing mark compared to where it is with the straight-up keyway. Then once I installed the timing set straight-up and released the tensioner I again looked at the timing marks to see how far they were off; I'd say the timing set has about 1* of retard, 2* tops meaning if I had installed it 4* advanced it would have actually been 2-3 seen at the cam. Good enough for me especially considering this is a fairly heavy car, advanced would have given me a bit more grunt but pinging is very possible with these engines even with the not-so-high compression. In fact the stock engine computer (basically a later version of Lean Burn) had a knock sensor and would retard ignition timing when lower-octane fuel was used because apparently regular gas could make it knock. Even on the gas filler door it says "Premium Fuel Recommended" lol!
 
ScampMike said:
So you're trying to decide if you should reuse the 360 piece you have or buy a new, top of the line race piece??? That's quite the swing. What you paid for the car doesn't compute here. You're there now - spend the $$ and replace it. Think of it this way, if that 360 chain fails on you - how much did saving that buck fifty just cost you? And I'm not saying you can't reuse the 360 piece, I just believe that one should go with new if the opportunity presents itself.
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What I paid for the car does kind of compute because I'm open to the possibility of selling this car at some point. Nobody looking for an old M-body Chrysler with a stock 318 will give a rat's a$$ that it has a billet true-roller cam timing set, they'll just be happy the previous owner even bothered to replace the factory timing set at all. While cool and super comfy this car isn't very practical, the trunk is wayyy smaller than my Duster's, the back seats have just "OK" legroom, and the lack of power doesn't really justify the poor gas mileage compared to a more modern car of similar size and power. I'd really like an older pickup truck TBH... a 1/2-ton Dodge with a 318 and manual trans would probably get close to the same MPG as this tank, and have a truck bed and towing ability to boot.
 
Many many years ago,I reused a chain that was so floppy I advanced the sprocket a full tooth. That was before I ever heard about degreeing stuff, and there weren't no such things as tensioners. The eyeball method looked good. And it was. Hmmmmmmmmmmm I wonder what ever happened to that old girl
 
MOPEkidD-3 said:
What I paid for the car does kind of compute because I'm open to the possibility of selling this car at some point. Nobody looking for an old M-body Chrysler with a stock 318 will give a rat's a$$ that it has a billet true-roller cam timing set, they'll just be happy the previous owner even bothered to replace the factory timing set at all. While cool and super comfy this car isn't very practical, the trunk is wayyy smaller than my Duster's, the back seats have just "OK" legroom, and the lack of power doesn't really justify the poor gas mileage compared to a more modern car of similar size and power. I'd really like an older pickup truck TBH... a 1/2-ton Dodge with a 318 and manual trans would probably get close to the same MPG as this tank, and have a truck bed and towing ability to boot.
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ok - makes sense - so why even consider, or mention, the good timing chain then? ..you can get a new run of the mill unit for $50ish. If you don't really care about it, and you're so sure the next owner won't care about - jam that 360 piece in there and be done with it. It actually sounds like you're looking forward to the experiment.. and the general consensus does seem to lean toward using the 360 unit. What's the worst that can happen? It fails and you maybe lunch a 318 in an '88 Fifth Ave. - all good.
 
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