I've got a 454 - .030 over, internally balanced, approx. 11.5:1 comp., solid roller cam. This is going to be a 7000 rpm engine, but will be driven 98% of the time on the street. I had a gear drive for it, but even though it is a "quite" drive I just don't want any whines.. Right now, I am torn between a link-belt and a double roller.

1. Which one is least prone to stretching and failure?
2. Should I pay the extra money for the billet steel sprockets?
3. Do I still need a cam button, since I am running a roller cam?

BTW - This is for a Mark IV block - (not a factory roller block)

 

I have had good luck with the Manley double roller with the built in torrington bearing on the back side. And for sure on the button.

 

good pick......

 

Thanks for the help guys!

 

This a pic of a basic $30 Cloyes 3 position set that has been in my 540 for years. It regularly turns 7500 rpm and has a solid roller with springs stout enough to hold up a house. Lots of track runs as well as street time. I'm pushing it with screwdriver to show stretch. This probably occured in first 5 minutes of running.

You will need a cam button for the roller cam. I also drill a small hole in the thrust face of the block to directly intersect the #1 main oil gallery. This puts pressurized oil to back of cam gear and will save your block.

You can spend a lot of $$$ on timing sets, but most is not needed.


JIM

 

In modern times you have to BEWARE! even Cloyes is packaging Indian made chains in their timing sets today. Double roller timing sets can have chains made by DID (Japan) or India, we found some of the Comp Cams timing sets had Japanese made chains but Cloyes had Indian ones. The good old French made Reynold chains are now long gone from Cloyes. Its kind of like playing roulette when building a motor in today's world where the parts are sourced.

 

there are actually two types of double roll chains, one for aftermarket performance and the other is Heavy Duty truck sets...unscrupulous engine parts sellers will sometime pass the cheap HD truck set for the more expensive 'true' double roller chains as novices will never know the difference in most situations...A note on OE sets with the nylon cam gear...they are in all of the Chevy engines including a factory L88...so they cant be that bad however the 'Cloyes' true roller would be recommended..for the best performance and longevity...the rest is overkill

 

I vote for both heat treated sprockets. I had a budget overhaul years ago that I used one of the cheaper sets on, like $40, and when the engine finally let go on an unrelated failure, I found nearly half the teeth broken off the cam gear. Likely because I was beating the hell out of the motor on track days and it spent minutes at a time at 5000+rpm.

 

Hey Jim,
I saw your engine tear down thread and was trying to find out which timing gear you had used, but google didn't help me that day. I ended up purchasing a Comp Cam timing chain that was recommended for the 288AR cam before the previous posters had posted.

I've read every little piece of literature that I've received from the cam, lifters, springs, timing chain, and everything and I feel like there is stuff I need and they aren't telling me. You say I need a cam button for the cam, but their cam directions don't even mention it.. I looked up the 288AR cam on Summit and under notes it tells me that I will need a thrust button and wear plate. I can't believe the literature doesn't even mention this!

Do you have a particular cam button that you recommend? Or, should I just buy Comp Cams' button to be on the safe side? And a wear plate? Is it necessary?

I don't know if Comp has made any changes since then, but the one I have says it is "American made". I guess American made and Made in America could be 2 different things?

L88's used a nylon cam gear? Wally, I think you have just changed my perception of the legendary L88! I mean a 7000+ rpm race engine with a nylon cam gear? really?

Thanks for your input! Now Im not sure if the timing gear I ordered has heat treated sprockets or not.. I know they are steel and not iron like most others.. What material was the cam gear with broken off teeth?

 

You see *double roller* and *true roller* advertised. The difference is the *true roller* has solid roller bushings on the pins. The regular double roller has a seam in the roller. Interestingly the *true roller* has smaller pins in the chain usually to allow for the different roller bushing.

Yes, nylon gears were used in some Hi Po stuff....some swear by them...I wouldn't use them. Just one less thing to worry about.

Mfg's are getting stuff from all over the world. Some is good and bad from each CO....just depends on what they ordered. I've seen good and bad from India, Argentina, and even China. A lot of the better steel stuff is coming from Japan these days.

And yes, there can be a big difference in what's called Made in America based on which state they are based out of. Some require you to *substantially change* the part...but the definition of what that is varies widely.

There are basically two style of cam buttons out there. Most are repackaging the same one with the little roller bearing on it. Just get one from Comp or Summit or Crane and you'll be fine. I've seen several of the plain nylon ones last forever with little to no wear. Actually surprised me how well they did..but really there is no big load on them...they just keep things in place.

The newer big blocks use a giant single roller chain that looks like a logging chain. I wouldn't worry about using one of them in a MKV motor at all.

You don't need the thrust plate setup for a MKIV...just use the thrust button assy.


JIM

 

That's funny that the Compcams would be different than the Cloyes. That's what they actually are, just reboxed for private labeling. That's a damn good timing chain. Never had one go bad.

 

I really like the Cloyes cover with integrated cam button.
http://www.summitracing.com/parts/CLO-9-231/
Combined with a Cloyes Hex-adjust double roller chain with thrust bearing and billet steel gears it is easy to install, degree cam, add advance or retard, available for line bored blocks, fits behind a short waterpump and is a real nice package. It is $300 for the setup though. Add up a regular double roller timing set or link belt, new cover, cam button, thrust bearing and labor to set everything up, degree cam and maybe advance or retard cam when on the dyno to get best performance it isn't priced to bad. Depends on what you want or need but running 7000+ RPM don't go cheap.

 

I bought a new 454, 78, 3/4 ton pickup put 52,000 miles on it longest milage i ever put on a gm product before i got rid of it. Pulled a 69 camaro trailer 5,000 lbs combined weight to the track one time with it 140 mile round trip thats by far the hardest it ever had to work. At 48,000 miles nylon timing gear sheared all the teeth off. The heat from the oil over time had baked the nylon made it brittle off came the teeth. Standing in line at the auto parts store to get a steel timing set, man standing right beside me in line had a nylon gear in his hand teeth sheared off, his was off a V6 ford.

 

I never meant to imply that the nylon OE stuff was any good for performance, its that they were used in all the engines except truck applications above C30`s....but including the 88`s. I know sort of shocking too....You dont need a expensive high dollar fancy one but a good Cloyes true roller set is what I replace all mine with when necessary...I guess GM figured that why use a high dollar set when they would be opened up for maintenance and changed anyway.......

PS, run the cam straight up....

 

GM, Ford, probably chrysler was using the nylon, all there damn bean counters wanted to do is make something barely good enough to get it past the warranty period. This kind of thinking over the yrs just barely make it good enough is a big part of why GM went bankrupt that and paying to much for labor costs from the top to the bottom.

Not to many could get any real use out of billit everything, but most likely the $20.00 timing sets are junk.

 

 

I've kind of gotten off the "Hex adjust" bandwagen after cracking 2 adjuster dowels when setting cam timing. Those EFFING things are BRITTLE, I think they are made of glass that appears to be metal

I'm installing an Xceldyne belt drive in my next "max effort" motor.

 

How about a little Cam Button 101. Where does this do, why do you need it, where does it go? Trying to do my homework on cams.
Thanks,

 

Flat tappit cams if you look close enough at one the lobe surface is ground at a slight angle so all the lifters are putting a backward force on the camshaft this keeps the timing gear/chain pulled up close to the block. On a roller cam the surface of the lobes are flat nothing to keep the cam pulled backward so in the early style blocks that originally came with flat tappit cams if you install a roller cam you use a button that mounts on the center of the timing gear it takes up the distance between the timing cover and the timing gear set so the cam will not walk forward.

In later factory blocks with roller cams used from the factory the factory made a step nose style cam then used a plate bolted to the block to hold the cam from walking forward.

 

OK.. then the next question is , what is considered an early block? I got a mid 70's block. I think its a 74 yr. What is the later factory blocks..?
thx,