I spoke with Larry at T&D rockers about the adjusters and he has talked with Jay Brown about them as well. He told me that they tested the adjusters and it took up to 60 ft/lbs of torue to break them and they should be torqued about 20 ft/lbs. They also installed them in a press and it took about 2 tons to bust them when pressing on them. He also told me that they in stalled in a vice and hammered on them and they held up real well. The only thing he can figure is that they got over torqued. I do know that he is sending Jay some more just incase a few bad ones got out.
I have used their products for about 15 years now and have had very little problems with them. Most of the top NASCAR teams are using them as well so I know they make good stuff. I have looked at the adjusters myself and can see no problems with them what so ever. I guess time will tell how they work but I also know that Larry stands behind his product unlike some other people we know. Good luck, Keith Craft

Sorry Keith, but I'm just not buying the overtorque thing. Larry and I had a long discussion about this. The adjusters I checked with a torque wrench were only at 13-14 ft-lbs. And if those adjusters can really take 60 ft-lbs of torque, its hard to imagine anyone breaking them with a 6" long 7/16" combination wrench. I just flat out did not torque them that much. Period.

I think at least two of the adjusters were just defective. There may be more. I think I may test all of the adjusters that I have, to 40 ft-lbs, to see if any more of them break. As long as you brought it up, I will try to do that and post the results by tomorrow night.

I'd be interested to see if anyone else has even run these rockers yet, and if so, what they experienced. Do you know of anyone?




Jay Brown
1968 Shelby GT 500 Convertible, 492" 667 HP FE
1969 R code Mach 1, 490" supercharged FE, 9.35 @ 151.20, 2007 Drag Week Runner Up, Power Adder Big Block
2005 Ford GT, 2006 Drag Week Winner, 12.0 Daily Driver
1969 Ford Galaxie XL, 460 (Ho Hum....)
1964 Ford Galaxie 500, 510" SOHC

The broken adjusters can be retorqued at a different position util they break again. This will provide good information.

I believe both Jay and Larry are accurately inspecting these parts, and that a logical reason for the failures will be found.

Shoe.

I got two sets from PSE 25 yr's ago an never had one come apart.Jay you must have gotten a few over harden adj's. Years ago when I raced my cammers they saw 9000 rpm ,now I drive them on the street one is in my 40 ford about 15000 on it. I did have rocker brake because high spring prsure for the street but ok now.I have been running cammer for 39 yrs.LOVE THEM john.

The adjusting screws are likely carburized, low carbon steel. If process is not well controlled, fracture can result. We produce similar parts for critical applications. Threads are typically J-series with controlled root radius. Also, mask threads to avoid quench cracks.
Fasteners of this design should have a defined and very predictable yield strength. Proper assembly requires assembly torques within defined yield limits.

...the manufacturer should have batch test samples from production, with proof of yield specifications and results.

........should have said was "I/we need to look into the problem Mr. Brown has discovered". To even imply that Jay caused the problem will alienate some people on this Forum, JMO, Rod.

Mickey Thompson's 63 1/2 #997 S/S Hi-Rise 427 Lgt/Wgt Galaxie,
1957 C-600 Cab-over carhauler w/390-4V, 2-speed rear-end
FGCofA member #4908
MCGC member #75

"There will ALWAYS be an FE in my LiFE"

He ran some tests at his place, torquing some of the adjusters to 40 ft-lbs without any failures, and then leaving them to sit overnight in case the adjusters popped later, like they did on my engine. He suggested overtorquing as a possible cause, but especially in light of the 60 ft-lb number that Keith threw out, that is simply not possible, especially with a 7/16" combination wrench. Larry also suggested that a couple of bad adjusters may have got out, and Keith said that as well. I don't really take any offense at what Keith said in his post.

At this point I'm pretty convinced that most of the T&D adjusters are OK, and that I just happened to get a couple of bad ones. Last night I re-installed 7 of the T&D adjusters, and torqued them to 30 ft-lbs (couldn't quite make myself go to 40). I had no problems. I will do the remaining 7 adjusters tonight.

Jay Brown

1968 Shelby GT 500 Convertible, 492" 667 HP FE
1969 R code Mach 1, 490" supercharged FE, 9.35 @ 151.20, 2007 Drag Week Runner Up, Power Adder Big Block
2005 Ford GT, 2006 Drag Week Winner, 12.0 Daily Driver
1969 Ford Galaxie XL, 460 (Ho Hum....)
1964 Ford Galaxie 500, 510" SOHC

way back when and opted for a non-adjutsable R/A for the reliability factor. Does anyone in the forum have access to SOHC SAE papers or any original Ford testing documentation
for the SOHC? They might speak to this type of failure issue.

and the SAE presentation. Adjusters aren't dealt with. And remember that the original design didn't use an adjustable rocker arm---they used lash caps of varying thicknesses.
KS

The 50 Cammers of 1964 got shim-type none adjustable rockers. The Cammers after that got taller valve covers (identifieble by the familiar "Ford 427 SOHC" logo cast into the center) which cleared the adjusters on the 2000+ Cammers made during the 1965-later period.

Shoe.

Non adjustable Ford SOHC rockers were very popular with the blown fuel racers because they stated there was a problem with adjustables breaking. I never asked what part of the adjustable rockers broke, RWJ

must of the non adj rocker came apart over the valve about 1'' back from end. john

That explains why the non-adjustable shim types may have remained popular after the adjustables became available.

The last version of the Cammer adjustable was apparently forged from steel, if I recall Jay's recent photo. This would suggest the adjuster was not the failing portion of the adjustable rocker - unless the adjuster screw was also redesigned (I don't think it was).

Shoe.

They have a better shear capacity than steel for vibration. I used them on flat track motorcycles with a SOHC twin. They were like kind od like a stock Ford SOHC, 1.27 ratio, elephant foot followers on the cam with direct action adjusters on the valves, I got them from a VW mini stock guy.

First - I've never built a Cammer...

Now that we have that out of the way, I have a couple observations/ideas which may (or may not) have some merit.

Unlike any other FE adjuster, this one rides directly on the valve. It is subject to scrub loads across the valve tip - something handled by a roller tip or a radiused bottom on rockers on a "normal" engine.

What does the valve tip contact point/contour of the adjuster look like? These could be subjecting the adjuster screw and/or rocker body to far more flex and side load than they would normally see in any other application. Anything that upsets the "flat to flat" contact of the lock screw to the rocker body tip will really focus loads against the threaded member - a logical fracture point. The factory rockers looked to be a really beefy & heavy/rigid forging.

With bigger cams and stiffer springs, those various thickness lash caps from first design SOHCs might start looking pretty good - in part because they'd allow a roller tip on both ends of the rocker.

Waiting for critics and comments......

Barry Rabotnick
Survivalmotorsports.com

Qualifier: I've never built a Cammer either.

There would be little tension on the adjuster threads at the valve side of the rocker. The adjuster would be clamped tight to the rocker threads near the locknut, far from the valve. Maybe there is a cyclical flex caused by the valve tip sliding back and forth at the adjuster that is naturally fatiguing the adjuster at the locknut. The rocker/locknut junction may end up being a "hard" pivot point for the rocking adjuster threads. If this is the case, counterboring the threads on the rocker to add a stretch distance may resolve this by defocusing the rocking pivot from 1/2 thread to 6 threads or so.

Shoe.