Tuner wrote: ↑
Sat Nov 30, 2019 4:43 pm
Somewhere in the waybachdaze in this forum was a link to a Cloyes tech bulletin that described during manufacture links are (were ?) sorted by length and separated categorically in short, long and longer, to be assembled as longer and shorter overall chain lengths. As I recall the measurement was optical (laser?) and the precision tolerance was less than .0001" per link. In another process the sprockets are (were?) measured for precise diameter and chains and sprockets are finally assembled and measured together and packaged as a set for precise fit to a specified cam and crank centerline measurement.
I looked through a large number of pages on the forum using simply "Cloyes" as a search parameter.
I found all sorts of interesting things (again) including the info from BHJ about the 20 to 30 degree temperature rise in the oil pan temperature
of a Chevy 292 run continuously at a critical rpm.
There are patents for optically sorting morse silent chain parts to avoid misassembly.
There have been many discussions about chain quality or lack thereof and custom set creation by mixing short chains with different sized gears. Many of the links given would need to be tracked down again as websites have been changed.
Re: Timing set for line bored SBC
by tenxal » Mon Feb 08, 2016 10:07 pm
Cutlassefi wrote:That's impossible, how are you going to do that? They all use a larger diameter gear(s) to take up the slack.
The Technical person I spoke with at Cloyes told me they use a combination of gears and chains that fall on either side of manufacturing tolerances to get the final centerline distance. In other words, a custom 'short' set may have standard gears and a short chain, a standard chain and larger gears or any combination of the three. Cloyes identifies their 'short' chains by a copper colored link for each .005 the length is shortened.
Re: Timing set for line bored SBC
by tenxal » Sat Feb 13, 2016 12:23 pm
Pic of the new .015 chain. As mentioned earlier, each .005 totallength difference from standard is denoted by a copper colored link. As measured with my Mitutoyo ball end .0001 (ten thou.) micrometer, the center-to-center dimension of all pins are the same, as are all the roller diameters. I've got the .005 'short' chain on it now and will get pics of it's deflection as well as the .015 'short' chain and post them.
Re: Some Q's on SBF timing gear & chain - thrust
by Daniel Jones » Mon Nov 19, 2012 3:16 pm
Most vendors of timing sets do not make the timing sets they sell. Instead,
they repackage the chain and gears from multiple vendors. You need to know
who made the sprockets and chains. One of the guys on the FE Big Block Ford
forum (FE Engine Specialist Barry Rabotnick) used to work at Speed Pro. When
he worked there, they had offshore companies trying to be suppliers, so they
piggybacked some chain and sprocket testing on an OE bearing durability dyno
run. The Rolon chain from India cost them the test motor a couple times when
it failed before the test was completed. Having recently disassembled a 351C
Ford that had a Rolon chain, I can believe it. This engine had approximately
8000 miles on the chain and it was stretched worse than the one I pulled from
my 5.0L at 163,000 miles.
A summary of the test results for the chains from Barry is listed below.
Speed Pro ended up using Dynagear sprockets and Morse chain but had some
quality control issues then Dynagear went out of business. After that they
sourced the high end Cloyes sets (which used high quality Renold and Iwis
chain) and the quality control complaints went away. Take a look at the name
on the sprockets and the name on the chain and let me know what they say.
FWIW, The Ford Motorsport 351C timing sets I've purchased have used the Renold
chain and I think some of the SBF used Iwis but the last FRPP 351C chain we
examined had no manufacturer markings on the chain. The middle and top of the
line J.P. Performance sets used the Iwis/Jwis chain. I saw some Comp timing
sets that were Cloyes but that can change and you really have to open the box
to know for sure.
I was discussing the timing chain issue with a local shop that does a lot of
351C work (owner owns a Pantera and Mustang with 351C's and the builder raced
351C circle track). They use and like the Rolon chain bt only the gold color
chain. The Rolon chain that stretched on me was black in color and apparently
the gold Rolon chain is their premium line. FWIW, that shop said it was as
good as the FRPP stuff they also use and you can buy the chain separately.
Barry mentioned that the sprockets tend to come from Rollmaster (Australia),
SA Gear (US but poor quality) and Cloyes (US, not pretty but good quality).
Avon also makes some sprockets but sources others. Dynagear (US) used to make
sprockets but went out of business. A bunch of the performance aftermarket
companies are selling the poor quality chain from India (Rolon), along with
sprockets from Australia (Rollmaster, J.P Performance) or SA gear.
Chain durability testing summary:
Iwis (German) - looks very nice but was not tested, but has excellent
reputation as an OE supplier, used in high end Rollmaster
and some high end Cloyes sets
Cloyes (US) - tested OK
Renold (France) - tested excellent, used in most high end Cloyes sets but not
Morse (US and Mexico) - tested excellent
Daido (Japan) - tested excellent
Tsubaki (Japan) - tested excellent
KCM (Japan) - looks very nice but was not tested
Rolon (India) - failed test
Rollmaster - Aus - pretty - never examined QA, good reputation
SA Gear - US - ugly - crappy
Cloyes - US - not pretty - good QA
Dynagear - US - out of business - so-so when they existed
Avon - some sprockets, buys everything else
Crane - buys everything
Comp - buys everything
Speed-Pro - buys everything
Ebrock - buys everything
Melling - buys everything
Elgin - buys everything
Note: Some of the test data was from Speed Pro, other from TRW.
Re: Broken timming chains
by Kevin Johnson » Tue Feb 14, 2017 8:21 pm
MadBill wrote:I recently read (possibly here) an interview with one of the 'name' damper companies. He talked of instrumenting customer engines to create 'bespoke' parts. He said that when they ran at critical RPMs, not only did the crank's torsional vibration increase a ton, but the oil temp rapidly rose as much as 20°. Just like a paper clip heating up when you bend it back and forth...
Re: Harmonics V's Oil Viscosity.
Postby bill@bhj » Mon Jul 26, 2010 11:29 pm
I can only partly answer the question -
While testing OEM crank dampers on an inline 6, (292 Chevy) we used to make a quick sweep across the rpm range to spot the general pattern of where the torsion peaks were, then go back and go very slowly across the rpm band where the worst peaks were to get a more exact reading of where those peaks were. We wanted the frequency of those peaks for fine tuning the damper. Inline's are not alone here, I just use it as an example - They usually had several nice peaks to contend with.
If we would set the engine directly on a high peak, (say .6° p-p) we would see that peak slowly rise (~20-30%) and see a corresponding rise in the oil temperature ( say 20-30°) Since the engine owner didn't want to pursue this any longer than necessary, we never sat there to see how high either value would go.
All it proved was that the torsion was enough to make each of the bearings into a small viscous damper which would absorb some energy at the expense of heating the oil in the bearings and consequently in the pan.
This was only an issue if one were going to have the engine run right at one of the torsion peaks when these peaks might be only 100 - 200 rpm wide at the worst amplitudes.
For an engine that was up and down the rpm range and just running quickly back and forth through the peaks, it was a non-issue. NOW, for a big speedway situation where the rpm may be in a narrow rpm band for a big % of the lap, you sure wouldn't want the engine to be sitting right on a significant torsion peak. For the NASCAR size V8's this is typically in the high 6000 - low 7000 rpm neighbor hood and is usually the 2.5 order peak. In that situation, oil heating in the bearings could get significant and the oil viscosity would be going down with rising temp.
So - The torsion peaks can be influenced by the oil viscosity - and vice / versa.
Also, the high rpm track motors can certainly benefit from careful sizing and tuning of the damper to keep from having the engine dwelling on a torsion peak. All those dampers aren't the same and not enough people are measuring their effect.
Re: Timing chain; how tight is too tight?
by MadBill » Tue Nov 23, 2010 2:50 pm
Rizzle wrote:I don't think .220 chain deflection becomes the same as growth amount for the block, since that has to come from both sides of the chain. However, how much does the chain grow from heat as well, since its got to generate at least a little heat?
Exactly right, slack is taken from both sides and even then .110" at the chain does not equal .110" possible movement between gear centers either. Chain angle ,( which will be determined by cam/crank centers), to cam/crank ctr/line will effect how much linear movement X amount of chain slack will allow.
You guys are over-analysing this. All that matters is the temperature change from ambient to running and the difference in expansion rate between aluminum and iron/steel. The former is ~ 13 parts per million in Imperial units for typical block material and the latter ~ 7 for most iron and common steel alloys. Since the sprockets, chain and block are all iron/steel in the first case, there is no change except for any temperature difference between them when hot.
For the aluminum block case, let's say the center-to-center distance crank to cam is 6" and the operating temperature is 200° F., an increase of 130° from ambient. The increase in c-to-c distance, and thus reduced chain slack each side is then (13-7) x 130 x 6 /1,000,000 = 4.68 thousandths.
Re: Comp timing sets...Any good?
by Barry_R » Mon Aug 25, 2014 8:41 am
Gears & sprockets:
Dynagear has been out of business for a decade. They used to make a lot of the industry's private label stuff. Not great, but was functional for stock rebuilders - and cheap.
SA Gear is still in business. They make a lot of the industry's private label stuff. not great, but was functional for stock rebuilders - and cheap. Was not as good as Dynagear back then - and cheaper. Might be better now, but I don't know that I am willing to take that bet.
Rollmaster - a lot of the race community is enamoured with this stuff, but my observations and experiences have not been as good. We find a lot of variable tooth shape and loose fit issues. I have "fixed" at least half a dozen internet/customer "loose chain" complaints where they thought they needed a -.005 set by sending them a standard Cloyes Tru-Roller set to try.
Cloyes is an OEM supplier and manufacturer. They are the only one I am aware of from the bunch that has passed any sort of OEM level production, development, or design testing/certification processes. Does not mean that their aftermarket stuff is as good - but if I were a betting man... My luck so far has been very good.
Cloyes purchased the Dynagear chain operations 10 years ago from the bankruptcy. They use that chain product in all their inexpensive and replacement timing sets. But they use outsourced chain in their top of the line sets - either Renold or JwiS. Probably a message in there
JwiS - German chain used in the top of the line Cloyes and Rollmaster sets. Seems to be very, very good.
Renold - French chain that used to be used in the top of the line Cloyes sets. Was very, very good - no idea whay Cloyes changed
Morse - American based OEM supplier. Used to see a lot of it, not as much anymore. Was very, very good.
Tsubaki - Japanese chain. Used to be used in older TRW sets. Was very, very good.
Daido - - Japanese chain marked "DID". Still found on occasion in some private label stuff. Very, very good.
Rolon - made in India. Used in most private label and low cost timing sets. I have had exactly two timing chains fail on me in perhaps 40 years of screwing around with cars. One failure cost me an OE engine bearing 100 hr durability test. One failure cost me a ton of valves and assorted parts in an SOHC Ford. Both occurred during dyno testing in fairly well controlled environments. Neither engine showed any sign of distress right up to the failure point and ran without issue once the damaged parts were replaced along with chains from an alternate source. If I find a Rolon chain in the shop I put on rubber gloves, pick it up with pliers and dispose of it in a doubled up plastic bag clearly marked as "hazardous waste". After sealing the bag I throw out both the gloves and the pliers.
WD for Comp, Manley, Blue Thunder, Diamond
Probe, Holley, Clevite, Federal-Mogul, Scat....
Re: Degreeing Cam Chain Stretch?
by Kevin Johnson » Mon May 02, 2016 3:15 am
digger wrote:The op is not talking about wear it's a new chain is how I read the post. Of course parts wear over time leading to the thing getting longer. Maybe it pays to shakedown the chain by loading it a few times before installing? When you do strain and displacement measurements on real structures you're supposed to load it and unload a structure a few times before recording measurments to get rid of relaxation kind of like running it in
A survey of literature from chain manufacturers reveals that many are quick to point out that their products are pre-stressed, pre-strained and/or pre-stretched and this is a sign of quality. Of the surveyed manufacturers, Timken is the most specific as to the process used.
FACTORY PRE-LOADED AT 50 PERCENT MUTS
Timken drives chains are preloaded to 50 percent of minimum ultimate tensile strength (MUTS) which is especially important for applications involving fixed center-to-center sprockets without take-ups. Applications can withstand shock loads up to 50 percent of the chain’s tensile strength without premature elongation.
During the assembly process, our roller chain is pre-stressed to avoid excessive early chain wear leading
to less frequent take-up adjustments.
Pre-stressed for higher accuracy.
Roller chains are prestressed to minimize chain stretch during initial running periods and for long lasting durability. Prestressing minimizes tolerance variations by providing balanced loading among all parts and avoiding premature fatigue failure. Shot peening increases resistance to fatigue. case hardening of pins and bushings means longer life for Browning chain.
Often the same or similar terminology is used when describing elements involving wear. It is open to discussion whether physical elongation of individual elements due to shock loads in use constitutes wear.