Timing Chains are one of the most critical components in an engine. On one side you have the 57-pound crankshaft feeding near-instantaneous acceleration and deceleration loads from idle to redline. On the other end you have a nine-pound cam and sixteen lifters, pushrods, rockers, springs, retainers, and valve locks that must be kept in perfect harmony.
All of that weight, plus a few thousand pounds of combined spring force, is a lot of mass to control at 7,000+ rpm.
And while you know that a Chevrolet LS engine loves more camshaft, you still have to keep it all in sync.
Turns out, there’s an easy way and a hard way to do it.
- The Hard Way: Double-roller timing chains are strong but don’t fit behind the oil pump and timing cover without spacers and grinding.
- The Easy Way: Premium, American-made Summit Racing Pro LS Billet Timing Chain Sets. These single-roller chain sets use an extremely high-quality roller chain for the ultimate in durability.
But these timing sets don’t just solve your timing problem, there are plenty of other reasons why you’d want to use one on your LS project:
- Made from precision machined billet to exacting tolerances.
- Precisely balanced with weight reduction holes to offset the weight of the 1x or 4x poles on the front of the timing gear. This reduces chain whip at high rpm for more accurate timing and less wear.
- Available in 1X and 4X versions for all Gen. 3 and 4 (1997-2015) LS engines utilizing a 3-bolt performance camshaft. LS7-specific sets are available as well.
- Available in standard, -.005 in. and -.010 in. lengths for align-honed blocks.
- They’re adjustable, with included captured color-coded degree bushings to advance or retard the cam in two-degree increments for a total of eight degrees either way. The crank sprocket is adjustable in four-degree increments too.
- Solve piston to valve clearance issues without the need to fly-cut pistons. Advancing the cam adds exhaust clearance. Retarding the cam increases intake clearance.
- Micro-finished pins reduce friction for more horsepower and reduced wear.
- They’re continuously tested for hardness, tensile strength, and dyno performance to ensure quality.
- Upper gears are available separately. They’re compatible with common OE-style LS2 replacement timing chains.
- Dampers and damper bracket kits are available for the early Gen. 3 engines that offer even more stability and durability.
These Pro LS Timing Chain Sets and Gears are part of Summit Racing’s growing Pro LS line of engine components initially introduced in 2018. Since its launch, the Pro LS lineup has continued to expand and includes forged pistons, rods, and cranks, along with a large selection of camshafts and valvetrain parts.
Here’s a complete list of part numbers and applications for the Summit Racing Pro LS Timing Gear and Chain Sets.
Summit Racing Pro LS Timing Gears & Gear Sets
Part Number | Part Type | LS Engine Application | Camshaft Gear, Bolt | Length |
---|---|---|---|---|
SUM-G6643-1X | Timing Gear | LS Gen 3 & Gen 4 | 1X, 3-Bolt | Standard |
SUM-G6643-1X-005 | Timing Gear | LS Gen 3 & Gen 4 | 1X, 3-Bolt | -0.005" Line Hone |
SUM-G6643-1X-010 | Timing Gear | LS Gen 3 & Gen 4 | 1X, 3-Bolt | -0.010" Line Hone |
SUM-G6644-4X | Timing Gear | LS Gen 4 | 4X, 3-Bolt | Standard |
SUM-G6644-4X-005 | Timing Gear | LS Gen 4 | 4X, 3-Bolt | -0.005" Line Hone |
SUM-G6644-4X-010 | Timing Gear | LS Gen 4 | 4X, 3-Bolt | -0.010" Line Hone |
SUM-G6645-1X | Timing Set | LS Gen 3 & Gen 4 | 1X, 3-Bolt | Standard |
SUM-G6645-1X-005 | Timing Set | LS Gen 3 & Gen 4 | 1X, 3-Bolt | -0.005" Line Hone |
SUM-G6645-1X-010 | Timing Set | LS Gen 3 & Gen 4 | 1X, 3-Bolt | -0.010" Line Hone |
SUM-G6647-4X | Timing Set | LS Gen 4 | 4X, 3-Bolt | Standard |
SUM-G6647-4X-005 | Timing Set | LS Gen 4 | 4X, 3-Bolt | -0.005" Line Hone |
SUM-G6647-4X-010 | Timing Set | LS Gen 4 | 4X, 3-Bolt | -0.010" Line Hone |
SUM-G6649-4X-LS7 | Timing Set | LS7 | 4X, 3-Bolt | Standard |
SUM-G6649-LS7005 | Timing Set | LS7 | 4X, 3-Bolt | -0.005" Line Hone |
SUM-G6649-LS7010 | Timing Set | LS7 | 4X, 3-Bolt | -0.010" Line Hone |
[…] Timing Chains are one of the most critical components in an engine. On one side you have the 57-pound crankshaft feeding near-instantaneous acceleration and deceleration loads from idle to redline. […] Read full article at http://www.onallcylinders.com […]
Who manufactures the chain?
Hello Ed. The chain itself is manufactured by Rolon.
What’s puzzling to me is that it seems the same oil pump cog is being used for both single and double row timing sets. Obviously the thickness of a single and double row gear will vary which will create harmonic balancer spacing issues. I ordered the single adjustable billet set and it actually didn’t have an oil pump cog with it, which is not that big of a deal, I realize that things happen and I had my cam degreed by the time I realized it.
I’m having a terrible time tracking down the correct oil pump cog and I’ve ordered three from three different vendors so far and while they pretended to understand my dilemma on the phone, they all sent SA Gear 13-3133 cogs to me. If I can’t find an answer soon, I’m going to measure the crank gear against the oe crank gear and either machine the gear off the stock one or machine one of my 3 sa gear cogs to make a spacer to get my balancer in the correct position. I sent Summit an automated request using my order history but nobody ever contacted me.
Hey Adam, thanks for the heads up. I reached out to the Summit Racing tech folks and here’s what they had to say.
“They do not use the same oil pump cog between the 2 sets. They also relieve the back of the double row gear by .055”. The front of the oil drive will be within +-.002” and will not alter the damper position or affect drive belt alignment. The additional thickness of the double row will require you to shim the oil pump out from the block face”
They also provided this table:
I’ll give you a few more details in a separate email soon–thanks for reaching out.