Lol, I learned my lesson from my last LQ4/Magnuson build. Way too much money and never again.... Put that into another 1st gen Camaro I had. While very fun to drive on the road, I never could really put down the power down. I just had a really nice smoker.... This next one is going very mild and dedicated for street driving to go back and forth to work or car meets.

LS3 with a 222-234 on a 112+4 with a .553 lift. Staying with stock valve train - except the upgraded pushrods and just swapped in a new set of GM LS9 springs

Almost done with this one. Thanks everyone for jumping in and answering my questions. Hope this helps the next guy.

 

In the ensuing 2 decades, have thoughts changed much on the necessity of double roller chains? I hear most often that a GOOD single row will do the job on almost anything.
I guess the real question is, what is the deciding parameter or condition that decides a 2-row chain is more desirable than a single row?

 

I have no proof, but I'm reasonably sure a duplex chain is stronger than a single. Many decades ago, the SBC ran Morse Hy-vo chains, which were stonger than a roller chain, and very quiet. But their downfall was GM using iron gears with bonded plastic teeth, thereby trying to make a "silent chain" even more silent . This is probably where the term "timing chain and gears" came into being. You have to use what are basically gears with a Hy-vo chain. The failure of this setup was the nylon gears cracking, or the plastic to iron bond actually failing. I had a friend who had a 1960s C3. It was one of the fastest street cars in our part of the State. Was being key, because he experienced the nylon to iron gear bond failure.......At over 140mph! It wasn't pretty, and he nearly lost his life. Valves thru pistons, you name it, it was probably junk after this happened.

 

Yes, there's been a change of view on 1x vs 2x roller chains and for all the right reasons in my opinion. The quality 1x timing chain sets are very durable and reliable.


History, opinion & rambling on how that occurred plus how I saw it "demonstrated" on my 416.

FEAR motivated the 2x rollers, quiet a few single chains, even C5R's snapped at high rpm in the early days resulting in carnage. Last night at the track or on the road course a timing chain snapped

Details weren't always forth coming many folks weren't on the internet then. The pattern was most often M6 cars but it also happened with A4 cars. The high quality 2x rollers seemed a little more safe, durable and more reliable.

It happened enough, I got an early Roll Master 2x Iwis for my H/C/I M6 99 T/A. My two friends in NASCAR, said **** Happens when you race, we'll deal with it, if it happensto you. BtW get a Fluiddamper or ATI if you want an under drive pulley. Car went together, ran flawless, more reliable than friends stock Ford's & Honda's.

In time the culprit was isolated. On aggressive down shifts, the LS1 timing chain whipped and if you had a cheapo no name under 25% under drive pulley, the harmonics could hit just right and snap any timing chain. Stopping the whip was the real fix but getting rid of bottom barrel 25% UD's also help improve control of the harmonics greatly.

Naturally road course M6 cars had highest risk and A4 drag cars the least with a whipping the chain & running a crap UD pulley - a bad combo. Being a Nervous Nelly when it comes to reliable, my 2008 built 383 LS1 also got a 2x roller. My NASCAR friend chuckled saying it wasn't needed for my build.

Fast-forward

By 2017 my NASCAR friend was in engineering management with McClaren doing Formula 1. So the TA's 416 build was with ERL, Reher-Morrison & Norris MotorSports. They rolled their eyes when I wanted a 2x roller timing set. They'd done 1,000's of cars with quality 1x's and no issues. The 416 got an LS2 timing set.

Later when the car was stolen and rev'd 10,000+ rpms on a missed WOT down shift, the 1x timing chain held up no issues. The valve springs not so much but it was repaired. That ATI & quality 1x LS2 timing set saved my 416 from being a collection of beer cans in somebodys refrigerator.

Next project, a stroker LS2 will be getting 1x LS2 or 1x Rollmaster timing set.

 

VERY thorough and thought out. Thank you! AND you confirmed my suspicions about the necessity of dbl. roller chain. They're NOT, for most cases, necessary....

 

The only thing I'll add is I have never seen a double roller break, period....

 

When you have 4x the required strength instead of 2x, it won't break. BUT single roller chains rarely ever break as well...

 

I have. It was a 15:1 383 SBC I built for running at Pensacola. Sure it was illegal, but if you don’t cheat up something down there, you’ll get lapped. I never started the engine, and sold it to a neighbor, who put it in a 68 Camaro. We removed the dry sump setup, and went wet sump with a pan that fit the Camaro. He put prolly 10k miles on it and it broke the timing chain. He ended up selling the engine years later for like $1500. The shaft rockers cost more than that.

 

I'll edit my post to "I've never seen a high quality double roller break." Yes, I'm sure that even with high quality duplex chains, it has happened. As for the duplex chain you saw break, a single row would've broken, too, and maybe even sooner, given equal quality and no defects. But the point of my post is that a double/duplex chain is stronger than a single row chain. They also make triplex/triple row chains. Physics, and logic, say the more rows there are, the greater the tensile strength. Is it needed? Probably not. Neither are 600hp engines, but it's nice to know that BOTH are there, if and when you need it. The frictional loss in power would be immeasurable at the rear wheels between single and duplex chains. To each their own.

 

To be fair, you wouldn’t believe the valvesprings we ran with that ginormous roller setup. I’m surprised the chain lasted as long as it did. Guys were running belt drives, but I didn’t see it as necessary, being as how your supposed to change the belt every 400 laps. We put 2000 laps on our chains. It was a very high quality double roller for what it’s worth.

 

There are higher quality and made in USA
And less $$ also. We offer them along with all the others, but i will only use the SA Gear billet sets on my personal stuff. Even the torrington thrust bearing is better along with oil feed channels for the bearing itself. Not an issue with clearance or chamfer either so no need to worry.

Ill post a video on our Facebook Page likely tomorrow to show the difference along with a few pictures. It uses a ROLON chain which is the same company that makes alot of chains for Cloyes and iirc makes the ls2 chain as well. I will be comparing it to a stock ls2 chain and maybe one of the 2 different IWIS chains available.

Rolon also made the IRL/RAIN chain if any of the OG LS1TECH guys remember it. Its definitely impressive and doesn't cost $150 by itself like a few others.

I may get some more actual evidence from the company we sent our trunnions to for strength etc. When time (and funds lol) are available there.

 

You wouldnt measure internal frictional loss at the rear wheels, but you could measure how much less dampening the chain allows due to it being less forgiving. Well not in your garage, but in a lab under controlled conditions ie spintron etc.

If the double rollers arent needed to 2k hp which is getting to be commonplace now, then why eve bother with all the grinding and spacing the oil pump farther away from the hole in the block and not seal it with anything ie o ring etc and just rely on clamping/deforming the alum spacers? Its unnecessary and not needed. Even at 9k rpm.

 

I am all for Made in the USA slapped on my parts (sometime its just the packaging though...), but I would also not hesitate to slap on MADE in Australia or Germany parts. R&D, quality of material and quality control win every time for me, not where it's made. Would love to see the comparisons.

SA GEAR has been my go to for my SBC and BBC builds in the past, but did not really look at them for the LS market. Actually not sure why, maybe because most places I shopped at did not promote them as much?

 

Who says they're not needed until 2k hp? If you follow that logic, forged cranks aren't "needed" either, until over, say 750hp. Many LS1 builds are getting by (for awhile!) with OEM cast steel cranks, and the OEM PM rods at the twin turbocharged 1,000hp level. Forged pistons aren't "needed" either, unless you're running real high rpm/nitrous/turbo's/blowers. But it's all an extra insurance policy. I've run double rollers for 100,000 miles, and never had a harmonics problem, or any other issues. As for labs showing microscopic differences, so be it. BUT, I've NEVER heard of anyone wanting more slack, or "give" in they're cam drives! It's also not a big deal spacing the oil pump, or slightly clearancing the inside of timing cover, which some engines don't even require. Most double roller sets include the spacers. Actually, I've never seen a any double roller setup that didn't come with shims. How in Hell are you going to "deform" the spacers? Also, youre worried about clamping force from 4 M6x1.0 bolts? Each one can apply thousands of pounds of clamping force, far more than an 80lb psi oil pump can provide!! Just tighten down the bolts evenly, which should be done even if no shims are used! Next to gears, which don't offer any "forgiveness", or harmonics dampening, a belt is probably the best setup, better than any chain, single, double, or even triple. These engines are basically a small block Chevy with different oiling, and much better flowing heads. What worked on the original SBC generally works on the LS motors. Theyre both nothing more than air pumps.

 

Its literally proven daily. Thats all the logic necessary. Dont have to worry about it on paper, people are out there doing it. Thats proof enough without going down a rabbit hole especially with unrelated parts and on assumptions.

 

Also trying to bring sbc or bbc timing sets or parts even into a discussion like this definitely isnt the way to prove a case.
Everything about them is so completely different there is virtually no comparison valvetrain wise.

 

Oh well if Small Block Chevy is fair game, I'll bore everyone with more of my high mileage stories 😀😃🙂

I seem to recall ~25 to 30 years ago my 91 RS's 305 had a single timing chain from factory. The damn thing had stretched and started the rattles by 30,000 miles. You could feel retard that went with the wear too. Ran it that way for a long time.

Finally replaced with a 2x roller. Mechanic laughed said that 170hp 305 TBI didn't need a 2x roller was massive over kill. I said whatever, want the best 2x I can afford cause I don't want to do this again ever.

~300,000+ miles later ran perfect no rattle and ran perfect . Over Kill is Good, Very Good sometimes


The Vette's Dart 400 also got a 2x roller 😀

 

I see your 2x roller and raise you two sprockets, lol.





I don’t think I ever built a street small block chevy without a double roller. I think that was the norm. I did get into gear drives for a while than got really too noisy as I got older and went back to 2x billet roller assembly.

 

I went to the double roller after stretching a c5r chain. Singles have been breaking if they havnt used a quality harmonic balancer.
i think rollmaster have 5 different length chains for ls so you can get them so theres minimal slack.. I have the cam plate with grooves so no need to camfor, dont know how i got it tho

 

On my original heads/cam ls1 car i owned many years ago it did 70k miles of street/strip beatings and went threw several different cam swaps. I used the same Rollmaster double red series chain from the beginning. The final day i pulled it down to swap out the cam/heads and return the car to standard to sell it, the rollmaster chain was still tight. I was impressed and sold on them ever since. Not saying other chains don't work but i don't see the double roller is a detriment. Now for people like Mick above running heavy springs because large solid roller... the extra force required to turn the cam against the heavy springs is being transferred from the crank through the chain. The chain takes even more of a beating. So why would you risk a single chain when the double has been proven reliable for decades in not just LS's but everything else as well.

Worst part for me was having to clearance the timing cover on my current LS2 for the double chain, was probably more of a pita than the entire engine build. I never had to clearance it on my ls1's for the double chain. I didn't bother looking into why that is or what the difference is, i just got the die grinder out until it fit.