You think a hybrid could be made with a roller at the fulcrum only and somehow fit a stock rocker shaft at a big cost savings?
Now you have me wishing I wasn't leaving my machinist job for a maintenance job! Grrr! Depending on the diameter of the stock shafts/I.D. of available bearings I would think it would be pretty easy.
There's a few brand "F"-centric companies doing that with good results..... http://stores.precisionoilpumps.com/fe-ford-roller-rocker-arms/ And, yes, I realize it's bushed and not a true roller.
Experience speaks volumes. The guys that have been around these motors for decades know you don't have to have roller rockers, and you don't have to have aluminum heads to run 12's. I can see both sides of it. Some people want the best and have the extra money around. Some people build using only what's needed and save the money for something else. I personally would rather stick with a .500" or less cam and run stock rockers than run a cheap set of aftermarket rockers. What happens to those rollers that break or the metal that is wearing off is not a good thing. That's why the guys using roller lifters are going away from the needles. When they fail they end up everywhere.
I think bushed would be easier to manufacture. Actually, I'm fairly confident I could do something like that, although 16 of them would be time consuming manually. For me, they would still be neat, as rigidity, adjustability, and ratio could all be made to what the user(s) (us) would prefer. Edit: if it were me I'd do something about replacing the plastic retainers, too. Another area with much room for improvement.
To be honest, I have no idea. I haven't done much observing to the stock stuff aside from bolting new stock replacements on. I'm on my first BBB, just applying general engine and machining sense to it. Maybe with the pay increase coming with the job change I'll magically be able to afford CNC equipment in my own home. Nothing wrong with dreaming, eh?
They are reputed to be 1.58 ratio vs 1.55 for 70-72. They don't wear the shaft as much as the 70 rockers, and they have a separate tip, not a roller, that rides on the valve stem.Some say you need to use a hybrid pushrod, I didn't and no issues.TA sells them in sets, or many times there are good used sets for sale on this board. They use springs to separtae the instead of nylon buttons which are prone to failure.
I used a 67-69 set for 10 yrs 9n my race motor, tons of trips over 6000 rpm with stk style pushrod ends. I was running over .525 lift when I started and ran up to .57x lift with these not failing.........to me that makes them better than the steel tubs
True, in the early 70's we didn't have fancy parts for these motors,had to use what was available and modify as we could for longevity. eg. Thumper had a 462 used lightweight venolia piston, light Howards rods, to minimize block movement,we had no girdle then. Still had to replace # 2 and 4 main bearing every year due to skirt movement,but she lived. 69 rockers, B4B intake, 1000TQ carb, KB high volume oil pump, KB MarkIV hyd. cam, 3/8" pushrods,KB stage3 heads, UNTILL I got some stage2 irons, then et dropped to 10.4 from 10.9,no other change. Still, antiquated by todays standards, a combintion that was simple yet reliable.
I have a nice set of poston roller rocks, 1.6 ratio blue in color. They have torrington bearings. Was told T&D made them back in the day.
For those of you who think they could buy the proform rocker and bush it.. Sure, if you have the tooling.. and the bridgport. I had a customer send me a set of these, to see if we could do just that, but by the time you got done buying the reamer and the bushing stock, making the bushings, and installing them, you have about as much money in them as a set of TA's.. We deemed it not worth the effort, and there are several other things wrong with that rocker. JW
The easy way to do that with no Bridgeport required would be to get a couple hand reamers to open up the holes in the rockers to the needed diameter if there is a bushing that can be purchased that would be a direct fit, then it would be ream, press in bushings, done.
Wrong ,,,Buick style factory rocker assembles are good if your head is in super good shape. But is Not. every head is off by a tad bit some how some way. adjustable push rods help if your head is warped more than likely it is . A machine shop does not straiten warped heads. They just resurface. Rollers have a bunch more advantages of stock assembles. even for a low HP motor.
What does "super good shape" mean? Why is that important for standard rockers, but not important for rollers? What does "straight" vs. resurfaced heads have to do with roller rockers if there's enough lifter plunger travel to accommodate the pushrod length? Name three advantages of roller rockers on low-HP engines.
None of those are advantages that roller rockers have over stock rockers on low-performance vehicles. The original rockers are a bit less than 1.6 ratio, but that's unlikely to be a disadvantage on a low-power engine. OEM-style rockers and buttons can and often did remain in service reliably, providing appropriate valve lift/duration for a hundred thousand miles, maybe more. Buy any valve covers that suit your fancy.
