SBC chains....

[mrvette]

On the double roller timing chains, is there any difference between the early blocks and the later on piece mainseal blocks?? the flat tappet engines vs the later roller blocks....L98 type, not LT.....

and when changing the chains.....can the old gear set be reused?? and of those two, which one gets the worst wear? the crank sprocket or the cam sprocket??? would it be a total sin to just replace the chain and maybe the crank sprocket and reuse the cam sprocket....??

thanks guys...

 

[clutchdust]

OK, GENE, I'm no expert on this but I believe the chains themselves are interchangeabe. The gears between the two are not, at least the cam gear isn't. The cam gear on the later, roller blocks are built for clearence of the retainer, which the early non-roller blocks don't have.
As for which gets the worst wear, typically it's the cam gear as in most factory and cheaper aftermarket sets the crack gear is hardened and the cam gear is just cast. I'm surprised you can even find a chain by itself.
But really, when you can get a brand new Cloyes for <$40, why are you even considering this?

 

[larrywalk]

Chains may or may not be interchangeable. Some chains use a roller (or pin) only .200" diameter; other higher performance chains use a .250" roller. Each requires gears matched to its pin size.

Previously, I used used double row chains, these always seemed to wear and become loose after a certain mileage, but currently, I'm using the double roller chains which don't appear to wear as rapidly.

OK, what's the difference you ask...
Both have double rows, but the double roller has a rolling cylinder around each pin which makes it more friendly to the crank and cam gears, lasting longer before stretch becomes an issue.

 

[mrvette]

Pulled the engine down today, heads are for tmrw....but have intake and front naked now...and the chain in there was a Cloyes double roller, and so after 14 years and maybe 100k miles, that rascle has only 1/2" of deflection on the slack side of the chain....most stock shit lasts maybe 1/2 as long and I seen enough slop to slap the covers....

I going to check the chain I have, but it's a Summit brand early block set, but being Summit and setting on the shelf here for over a decade, I wonder about if it's worth the bother....is the quality there??.....and today, I getting prices for a Cloyes double roller at about 150 bux.....4x any 40 buck figger....

so at that point I really dunno WTF....

:bonkers::flash::goodnight:

 

[Twin_Turbo]

no, the cam sprocket on a roller cam is different, the 3 bolts are not on the same bolt circle either, it will not fit

 

[mrvette]

no, the cam sprocket on a roller cam is different, the 3 bolts are not on the same bolt circle either, it will not fit

I know the cam sprocket is different, was wondering if the chain would fit...and so I would have to check the roller sizes.....

what do you think of 1/2 inch chain deflection?? loose or still good to go??

:beer:

 

[MYBAD79]

I would only replace the set.

$40 set vs $150 set.... you pretty much answered your own question about this one ... the good stuff lasted 14yrs and 100K miles...

If you're not planning on another disassembly in the next 50K miles then I'd replace it - my main reason is my own lazyness, I wouldn't want to drop the oil pan and go thru this mess if I can avoid it....

why are you taking the heads off ?? Got new heads ?? Didn't you want a different cam a few months ago ??

 

[mrvette]

I would only replace the set.

$40 set vs $150 set.... you pretty much answered your own question about this one ... the good stuff lasted 14yrs and 100K miles...

If you're not planning on another disassembly in the next 50K miles then I'd replace it - my main reason is my own lazyness, I wouldn't want to drop the oil pan and go thru this mess if I can avoid it....

why are you taking the heads off ?? Got new heads ?? Didn't you want a different cam a few months ago ??

Well, if the weather not too painful, I pulling the heads today, got the induction/front all apart yesterday....when changing the induction and putting on the remote stat housing, the temp sender is now in the housing, and it need be put in the head....but the damn steel nut in the pass head is in there too damn good, and so stuck, it's stripped and cant be removed in that position...the induction has had oil leaks from the china walls....and I want to paint it anyway....and change a couple other things around, nothing major, clean up the engine compartment, cover some of the wiring, tons of detail shit....I maybe even get super ambitious and redo the plug wires....yawn, then again, maybe not.....they work....

but redoing the cam would require removing the rad support assy....whole damn mess, 6 bolts and outta there.....the chain, ten years, shit, I"m age 67, think I will save the money....

:clobbered::zzz:

 

[larrywalk]

Half an inch of slack is too loose - time for a replacement.

 

[mrvette]

Half an inch of slack is too loose - time for a replacement.

HUMM....ok, any other guys....opinions??

:gurney::drink:

 

[Twin_Turbo]

buy a new set, summit house brand is nice quality I'm 99.9999% sure it's the same as the trickflow one but at a reduced price. Comes w/ torrington bearing if you like that too.

 

[rodeck350]

That dude from Italy (Panic) had a problem with his double roller. It shredded and left a hand full of metal bits in the oil pan. The peaks of the sprocket sheared off.

I think the stock design is more robust although it may have a propensity to develop more slack. I think you hit a point of max stretch though. I have never heard of a stock steel chain and gear failing.

Hell just set a little more advance in the cam to compensate for stretch.

 

[mrvette]

That dude from Italy (Panic) had a problem with his double roller. It shredded and left a hand full of metal bits in the oil pan. The peaks of the sprocket sheared off.

I think the stock design is more robust although it may have a propensity to develop more slack. I think you hit a point of max stretch though. I have never heard of a stock steel chain and gear failing.

Hell just set a little more advance in the cam to compensate for stretch.

From years past...I don't remember GM, F, Mopar ever using anything BUT plastic cam gear teeth over aluminum cores....and they shattered like MAD at the 60k mark.....so much so that I would just replace them out of hand....
this is the first time I ever bothered to use a roller chain set on a fresh engine build....but it was intended as a hot rod vette....AND DD use....

I put a tad of advance on it when installed...

I thinking of leaving well enough alone....going to bolts the heads down tomorrow, and maybe a seyance or premonition will come overnight as what to do with the cam/chain.....

:clobbered::nuts: