C.A.T. SS rocker ?

[dirttrackracer]

I have a set of the CAT stainless steel rockers 1.6-1 for a small block. The shafts that came with the set have 3/8" holddown bolts and every head I've evre seen uses 5/16". also the shafts have a very rough finish.I read somewhere that the shafts that come with these are not compatible and the rockers will gall on them.If I remember correctly the sugestion was to have the rockers bushed. I had to remove quite a bit of material to clear the bigger springs that I'm useing and it leaves little material to put bushings in. Would useing chromed shafts work with these rockers or maybe the MP banana grove hardened shafts? I really need to get this motor finished. Any help or suggestions would be greatly helpfull.

[dwc43]

Buy a set of Harland Sharps with the proper shfts included and get rid of that china junk. They are cheap junk, that's why they have problems with them. It's up to you.

[dirttrackracer]

I was using the crane gold rockers for several years then one of the pins that go thru the roller fell out causeing a valve to drop. Got to looking at the rest of the set and found several of the pins were loose. Got these CAT rockers in a hurry to get the motor ready for the next race but could not install because of clearance problems. Borrowed a set of rockers for the rest of the season. But now want to finish the motor for this year and really can't afford to buy the "good" rockers. Would like to use what I have if anyone has had experiance with other shafts on these rockers. If everyone says to not use them with good explanation I will install set screws in the crane rockers to hold the pins in. that should keep them from backing out. I have the shafts that came with the crane and they are chromed and also have a set of the hardened banana grove shafts so I don't really have to buy anything. I would really like to use the SS ones as they are really a nice piece other than the shaft problem.

[toad490]

If they are the unbushed rockers DON'T use them. They will seize to the shaft. Jamie at CAT called it a "metal incompatability" problem. Here's his email address. He said they would replace mine with thier new bushed rockers.

jamiea@catpep.com

I choose them for the same reasons you did, the fewer things to go wrong the better, and the price. If your not going to twist it much past 8,000 rpm the bushed rockers are fine.

[dkn1997]

the only problems I have ever heard about the cat rockers is with the stainless ones w/shafts. It sounds like they are addressing the problem. The only problems I have ever heard about the other cat rockers are from people who have not used them and feel the need to tell the rest of us how they suck.

[70AARCuda]

Originally Posted by dkn1997

the only problems I have ever heard about the cat rockers is with the stainless ones w/shafts. It sounds like they are addressing the problem. The only problems I have ever heard about the other cat rockers are from people who have not used them and feel the need to tell the rest of us how they suck.

I second your statement...

been using the aluminum roller rockers for a couple of years...NO problem...

:blast:

[dkn1997]

I second your statement...

thanks, and I don't mean to sound "pissy" but the endless bashing of the cat rockers gets tiring to look at after a while, especially when most of the time, those who bash have not used them. they assume that because they are not $500.00, they must be bad. (I can only speak about the aluminum roller rockers they make, because that's what I run.) as stated earlier, the ss ones have problems. (looks like they are trying to make things right)

However, I can understand when someone gets on us cat rocker buyers because we are not buying american parts. If the world was perfect, I would love to have the money to buy everything on my charger from companies who manufactur it here. But this is the real world where not only do budgets exist, but it is becoming very hard to tell just what is made here and what is not.

[toad490]

I'm lucky all the parts I buy are forgien made, no morale delemia. If you can call $750 plus 14.5% taxes for a set of BB Crane rockers lucky. With prices like that I started shopping around.

[fastback340]

Nothing wrong with alot of the so called "china junk" that gets bashed on every mopar site around. Some people need to build there cars on a budject and have to shop around. I know I cant afford a $600 set of Harland sharps.

[toad490]

As I've said on another thread it doesn't take much training or skill to push the green button of a CNC machine in the morning and the red one at night.

Lets face it budget is the reason 90% of us aren't running a blown all aluminium Keith Black hemi. And you don't hear the 10% that can afford one tell us not to waste our money on a wedge. Build what you can, or want, and then run it within the parts you've used. Isn't thats what it all about?

[fastback340]

Wait you've got a big block ?

You must be rich !

[toad490]

I'll tell ya how rich I am. I drove a 92 geo since new so I could buy my 70 Cuda last year. I'm not driving it for another 12 years for a engine!

[fastback340]

I here you. I have to drive a Chevy too.

[dkn1997]

Originally Posted by toad490

And you don't hear the 10% that can afford one tell us not to waste our money on a wedge.

Unfortunately, toad, that's kind of what is going on. A recommendation is one thing, but some love to say with certianty that anything they don't use stinks. they don't leave any room for any kind of discussion. It's "I don't use that and if you do, then it's wrong"

[sanborn]

Let me try to be of a little help.

First, I don't know anything about CAT rockers---or the Crane rockers for that matter---Please keep that in mind.

About the aluminum Crane rockers first. The "press" pins are fine for medium duty use(limited lift, limited RPM, limited spring pressures, etc.). But, when installed on oval track engines, engine heat becomes a factor. With heat comes expansion of the aluminum rocker and the steel pin doesn't expand as much---so there is a natural "loosening" of the pin with each heat cycle. In addition to this natural loosening is the rocker geometry/alignment problem. If the "push" of the pushrod is absolutely straight on the rocker and the rocker tip is absolutely centered on the valve tip side forces aren't too great. But, if side forces are applied at the same time as heat allows loosening of the pin---then you could be in trouble. DON'T drill/set screw the pins. You will probably weaken the rocker arm tip too much. The best way is to use hardened pins with snap ring grooves machined in them. The snap rings help to hold the pins in place(That's what the high $$$ Jesel/T&D rockers use). The "Econo" Jesel/T&Ds use press pins---they have the same problems.

Now to the CAT stainless rockers. The expansion rate of stainless is about the same as the steel pins. You probably don't have a pin problem. But, you do have a compatabily problem. Steel doesn't rub on steel very well(even with oiling). Usually the stainless will inpart to the hardened steel shaft. Your only solution (for oval racing) is to use bushings. The bronze bushings are softer than either but will prevent "galling". The bronze will ultimately need replacement but usually only after several thousand laps. This leads to your next problem---clearance. The large diameter springs(which the rockers probably weren't designed for) requires machining a "notch" for clearance. If done properly, the notch doesn't hurt the strength much--because the max depth of the notch is only about 1/4" wide. But if you do it by hand you probably remove more metal than needed---and that's bad. But keep in mind that stainless is stronger than steel and if the thickness of the rocker is greater than .100" in the area of the notch(after bushing) you will probably be OK. That's the way Norris stainless rockers are made----and they hold up well.

I hope my "mindless" rambling makes some sense to you. The decision is yours---Keep in mind, this info may be worth what it costs you!!!

[djswwg]

good post Sanborn............djs

[toad490]

Would useing chromed shafts work with these rockers or maybe the MP banana grove hardened shafts? I really need to get this motor finished. Any help or suggestions would be greatly helpfull.

Dirt, if your still there, If your want to try them I'd go with the banana grove shafts to get oil to all the parts of the rocker. If you can, get a set of aluminium hold downs. They'll keep the shaft round when torqued down and absorbe harmonics. I picked up a set on ebay for $65. Find a junk motor install them and put them thru some abuse and see what happens,eh?

[dirttrackracer]

Thanks Sanborn and everyone else.. I have contacted CAT and am waiting to see if they will replace the rockers. As far as setscrewing the alum rockers I figured that if I ran the screw from the underside I wouldnt be weakening a stress point. I run less than 400# on the nose spring pressures so It should hold up.
I'm hopeing that CAT will do something for me and I can get this solved with the proper parts. By the way the Cat rockers use the "E" clip pins.

[megajoltman]

Originally Posted by toad490

I'm lucky all the parts I buy are forgien made, no morale delemia. If you can call $750 plus 14.5% taxes for a set of BB Crane rockers lucky. With prices like that I started shopping around.

I've found it alot cheaper to get a U.S. mail box in a close boader town, buy your parts online or over the phone get them sent to your post box pay the taxes and any duty (if any) at the boarder and your not paying broker fees or part stores mark up.

[toad490]

MJM I buy 90% of my parts off ebay and when possible I get them to use regular mail, the shipping is low and the border fee is only $5 and only if you owe duty. A lot of guys will put "used parts" or gift on the form and then there's no duty or taxes. This morning I picked up a used eddlebrock TM-7 intake for my 440 for $76 US shipping will be $25 or so.

[megajoltman]

That's cool Ebay scare's me with all the scammers lately, I buy most of my stuff new from the parts guys down there to much mark up here with the local stores.

[toad490]

MGM, if you stick to sellers with good "feedback" you'll be okay. After a deal is completed both seller and buyer leave a comment on the deal, Positive, Neutral, or Negitive. If they have less than 100 deals I like to see 100% feedback and over 100 deals 99% or better. The sellers precentage is shown in each listing along with the date they joined. Stay away from newbies, out of 143 deals I've had one bad deal (when I didn't follow my guidelines) and my money was refunded by Paypal, thier online payment service. Most credit cards have online fraud insurance.
The main problem you run into is with the fitment of the part. Ask the seller for a part number and check it out yourself, don't take thier word for it unless your sure their right.
Think of it as the worlds biggest swap meet and have fun. I've found things I didn't even know I needed!

[dirttrackracer]

C.A.T. has agreed to take the rockers back even though I have ground on the for more spring clearance. Hows that for cusomer service! You won't find many manufactuers willing to do that.
They are going to send me a set of the bushed rockers in exchange.

[toad490]

Thats great DTR, I was also pretty impressed with how they backed up thier stuff. I thought Jamie would take care of it for you. Let us know how they work out for you.

[moparmotorman]

What about the ductile iron adjustables? I know they're old school, but aren't they affordable and durable?