I was reading car craft the other day, and I remember reading that most gearheads upgrade to a double-roller chain during a motor swamp. I was wondering what the extra cost of one is and its advantages.

I believe they're around $50-70. More accurate and less stretch I would think.

O'Reillys sells a cloyes double roller timing chain for $20. Its what I have on my engine, and its working great. I jsut had the timing cover off last week, and the timing chain is still as tight as the day i put it on after about 1500 miles.

The roller is easier to turn=more efficient.
Less heat.
Less wear.
More accuracy.

I paid abt $79 for my Cloyes "true" double roller timing set from Jegs.

I don't think the $20 Cloyes is the double roller.

The last longer and the true rollers are supposed to last longer free up HP with less friction. I personally dont recommend paying 100+ for a true double roller chain set the Comp "true double roller" that I paid wayy too much for seemed to have the same amount of strech as the cheapo $16 DynaGear I got from Azone.

"Ward" O'Reillys sells a cloyes double roller timing chain for $20.


Yes WE do!!


Peace

The reason its $20 is because its not a true double roller. It doesnt use rollers on the chain links, but it's still better than stock.

Exactly... the $20 chain looks like a roller, but it's really built with bushings inside it, not rollers. The $75 sets actually have roller bearings.

IMHO a cheap "bushing roller", AKA "truck chain", is worse than the usual stock style chain. I refuse to use them. They don't hold up. There is actually less load-bearing area in one of those than the stock kind of chain. I have no idea where the notion that they're better than the car type of chain came from; they're not.

1,500 miles isn't even the first full oil change interval on an engine. That's not long enough to evaluate any kind of long-term wear. Come back and look at it after 101,500 miles, and see what really happens.

I'll take exception to some of the comments made here. Twenty years experience in industrial power transmission and drive systems has educated me better than that.

First, the roller chains are not more accurate. The pitch lengths of most roller chains is longer than that of the Link Belt silent chain. (Link Belt is the brand and original patent holder.) Because of the longer pitch ANY wear and stretching introduces a larger amount of slack or lash in the drive, so if anything they are less accurate by basic design. Also, the intermeshing, folding plates of the silent chain act more like gear teeth in the sprockets, and tend to automatically take up lash where they wrap the sprockets under load, whereas a roller chain only stretches more and introduces more lash.

The roller chain type timing drive will not "outlast" the stock chain. It will certainly last longer than a stock chain with the older style plastic-toothed cam sprocket (yes, SPROCKET, not gear), but will not outlast a cast sprocket/silent chain setup. GM hasn't used plastic toothed cam sprockets for many years now, so you can probably forget your old notions about the plastic sprockets wearing out.

A roller chain is also weaker than the Link Belt silent chain drives. Study any good reference on power transmission equipment and you will discover that an RC35-2 drive will transmit far less torque than a silent chain before failure. That doesn't mean a roller chain drive is too weak. They are sized correctly for the application and should transmit the necessary power without failure. But that certainly doesn't make them stronger, just adequate. I've seen single width silent chains operate virtually forever in drives that would stretch the side plates of a roller chain double its size. There just isn't that much longitudal bearing strength in a roller chain link, even if it is double wide with four plates.

What is in favor of the roller chain drives is mass. They are a lot lighter than the silent chains, which means they consume less power and accelerate faster. They also tend to be a little more forgiving of shock loading, which shouldn't normally occur in a timing/distributor/oil pump drive, but it can occur.

Another factor in the true roller chains is reduced friction. By design, a silent chain will slide its plates into the sprocket teeth, creating energy loss, heat, and friction. That is evident in a used silent chain drive since the pattern created in the sprocket teeth by this wear is fairly obvious. A true roller drive has minimal sliding friction and mostly rolling friction, which is a lot more efficient. More efficient = less wasted power.

And as stated earlier, be very careful about your selection, since not all roller chains are created equal. If you can take advantage of the lighter, more efficient drive, then do it. If you really want the greatest efficiency in your timing drive, trash the metal and install an HTD belt or Gilmour belt drive. It is lighter, stronger, and even more efficient than the roller chains.

Just my 2¢

You should never swamp your motor, they don't like water inside them.

Unless it'a Misubishi. All of them are marine-duty engines, i.e., made to bolt a chain to and be used for an anchor. If you're in a swamp, so be it. It'll work just as well there as in a river or lake.