Just purchased a Cloyes 9-3100 timing set from Summit for a 355 I'm building. I was surprised to find the .250 rollers are split, versus 1 piece. I've read the Cloyes 9-3100 has a True Roller Reynold 9-130 chain which has a concentric ground split roller pins. The pins in the Cloyes 9-1100 are extruded solid roller seamless chains and are not ground true. Both are .250" O.D. rollers. The sprockets used are the same iron cam sprocket and steel crank sprocket for both timing chain sets but the 9-3100 set is hand matched. There is a a $60 difference between the original "race" 9-3100 and the "street version" 9-1100 so I'm wondering if the supposed chain upgrade justifies the $60 additional cost. Application will be solid roller or flat tappet hydraulic as I haven't decided yet, either cam will run double springs.
well you bought it so I guess it's yours. AFAIK, None are "ground" true, true means roller truly rolls on pin as some do Not roll on pin The lesser $ roller is cut from a tube; the higher $ roller is "split" because it's formed from a small flat piece of steel. Both 9-1100 and 9-3100 have 58 Links w/ smaller diameter rollers and both truly Do roll on pin; Both are Double-row chains OTOH C-3055 has 46 Links w/ larger diameter (& wider) rollers that truly Do roll on pin; But it's a Single row Heavy Duty chain. Unless you have really really heavy springs, will routinely run high rpm for long time and Must have three keyways; suggest the Single row C-3055 because it's a really stout piece and you will Not run into the situation of having to clearance the block like some do with double row chains. C-3055 less $ than the other two. JMO, too many folk just fall in line believing their motor HAS to have a double row chain; most don't. Many folk think Rollmaster timing sets with IWIS chain are as good as it gets; I agree. JMO YMMV
When I put a cam in my LS3 I used the IWIS chain (single roller), 3 bolt cam gear and dogbone tensioner/chain guide, after ~ 20K miles which includes numerous track days all is well. Old habits die hard so this engine along with all the pre LS Chevy's I've built have had and will have the double roller chain. Both the 9-3100 and 9-1100 kits have .250" rollers that actually roll and are visibly larger than the bargain basement double "roller chains" that the rollers are stationary. I was trying to find out if the real difference between the 3100 and 1100 just boils down to chain quality and the 3100 chain & sprockets are matched per Cloyes. I like the 3 keyways along with offset crank keys when dialing in the cam.