Bang! Bang! Bang! Bang! Bang!

[machoneman]

T&D!

http://www.network54.com/Forum/74182/thread/1378766821/PRW+rockers

[drdano]

Yikes
What rockers are those?

Those appear to be narrow Comp Cams (Dove) rockers.  What spring pressures are you running with that roller cam?  What are the specs on the cam?

[ScotiaFE]

I'd say they are POP rockers.

[machoneman]

PRW's?

http://www.network54.com/Forum/74182/message/1378780530/PRW+Rockers....

[ScotiaFE]

PRW's?

http://www.network54.com/Forum/74182/message/1378780530/PRW+Rockers....

The one that failed in this thread are POP rockers. Made in the good old USA and advertised on the FE forum.

http://stores.precisionoilpumps.com/-strse-43/FE-Ford-Roller-Rocker/Detail.bok

[lovehamr]

ScotiaFE is right on this one, they are POP rockers BUT I must add that I bought them used over on that other forum.  They appeared to be in good condition when I got them but obviously I can't say that they didn't have issues then.  For that reason I'll not bash POP.  I'm also using one of his oil pumps and it seems to be absolutely first rate.

The cam is a Comp with;
Int .645" and 242 @.050
Ex  .635" and 248 @.050
Lobe sep is 110

I can't remember what the spring rates are and can't seem to find it in my notes but they do match the cam.

Steve

[My427stang]

I haven't used a set, but T&D street rockers seem to be the rocker of choice since Erson stopped

I hear they are pretty nice, probably going to go with a set on my 445

[ScotiaFE]

The issue I see with these rockers and others, whether US or another country of origin
is the use of the stock shaft @ 0.842ish and the thin strap that holds it on the shaft.
The T&D rocker shaft and the old Erson setup are 0.625 inch shaft which allows for a much
thicker strap.
Lets face it, the cam that is spec'd here is not a tiny cam. The springs would have to be in the 500 + lbs range.
I would not consider POP rockers to be "HEAVY DUTY". jmo

[jayb]

The real issue with any of these rockers is that they are made out of aluminum.  Aluminum has a fatigue life, and every aluminum rocker arm will fail when it gets to the end of its fatigue life.  Some are better than others, of course, and with light spring pressures many will last a lifetime.  BUT, when stressed, all of them will eventually fail.  At Drag Week yesterday at Indy I was walking through the pits and a guy ran up to me asking if I had a replacement T&D rocker; he had one of the good ones that had just split in half.  Unfortunately it was for a small block and the spares I had with me were FE rockers, so no joy for him.  But even the really good, expensive T&D rockers will fail; Jack Miller had a few fail on Drag Week in 2007, at Wisconsin International Raceway, on his supercharged FE.

What we really need is a decent steel rocker arm for a reasonable price, like the old Isky rockers.

[ScotiaFE]

Now all we have to find is a FE addicted guy with a big fast mill and will to make parts at
pretty much cost.
Hmmm... now where would we find a guy like that?

[turbohunter]

ScotiaFE is right on this one, they are POP rockers BUT I must add that I bought them used over on that other forum.  They appeared to be in good condition when I got them but obviously I can't say that they didn't have issues then.  For that reason I'll not bash POP.  I'm also using one of his oil pumps and it seems to be absolutely first rate.

The cam is a Comp with;
Int .645" and 242 @.050
Ex  .635" and 248 @.050
Lobe sep is 110

I can't remember what the spring rates are and can't seem to find it in my notes but they do match the cam.

Steve

I seem to remember Doug saying he had a problem with his early rockers and will replace any problem. Since you bought these second hand my wag is you got early parts.
Of course not forgetting what Jay said about aluminum fatigue life.

[jayb]

Now all we have to find is a FE addicted guy with a big fast mill and will to make parts at
pretty much cost.
Hmmm... now where would we find a guy like that?

You're a funny guy, Howie 

[afret]

The issue I see with these rockers and others, whether US or another country of origin
is the use of the stock shaft @ 0.842ish and the thin strap that holds it on the shaft.
The T&D rocker shaft and the old Erson setup are 0.625 inch shaft which allows for a much
thicker strap.
Lets face it, the cam that is spec'd here is not a tiny cam. The springs would have to be in the 500 + lbs range.
I would not consider POP rockers to be "HEAVY DUTY". jmo

On the other hand, the smaller diameter hollow shaft with the four holes for 3/8" rocker studs/bolts are weaker around the bolt holes.  Even with the end stands, you see cases of broken Erson shafts but don't see as many broken .842 diameter shafts with end stands as far as I know.

[jayb]

I think that's right; I've broken those Erson shafts just getting them on and off the engine because they are hollow with the smaller diameter.  The T&D race parts oil through the pushrods, so the shafts are solid and pretty durable.

[drdano]

I didn't see one in the photos, but are these bushed or non-bushed rockers?