PRW roller rockers under Lemans covers

[shelbydoug]

Great input. A fellow forum member sold me an unused set of Blue Thunder valve covers today so I can check that item off the list. My builder had several of the same opinions about the longevity of steel rockers compared with aluminum. He said the measured spring pressure on the BBM heads was right at the limit of what he would put on a factory cast rocker so we moved up the strength scale to the stainless. I think we made the right call for a street motor that I want to be reliable and driveable. Getting ready to order the rest of the valvetrain. Good times ahead.

Hey! We aren't know it alls here. Some are very experienced, learned through the school of hard knocks with no one helping us out. We are trying to help you not make the same mistakes. Best of luck.

[The Going Thing]

I don't know who your builder is but stainless roller add quite a bit of weight to the valve train. Harland Sharp used to be US made. They are no longer.
Doug @ POP and Lykins are both FORGED  aluminum.  Many are running roller cams with 400+ pounds of spring at their specified lift.
I am at 365 LBS open. Stainless doesn't mean they're stronger. However, they ARE heavier and the PRW are know for being weak.  There are several pictures of failures and wiped cam lobes and broken roller lifters.
Don't take my word for it. Go look at the FE forum and Fe Power Forum.  There are several threads.  Even some of the thin deck surfaces on Chinese FE cylinder heads sold under the PRW name and others.  Many of the FE power forum members are actually real racers. 
I am not trying to let the air out of your balloons, just giving you a heads up.

[shelbydoug]

I don't know who your builder is but stainless roller add quite a bit of weight to the valve train. Harland Sharp used to be US made. They are no longer.
Doug @ POP and Lykins are both FORGED  aluminum.  Many are running roller cams with 400+ pounds of spring at their specified lift.
I am at 365 LBS open. Stainless doesn't mean they're stronger. However, they ARE heavier and the PRW are know for being weak.  There are several pictures of failures and wiped cam lobes and broken roller lifters.
Don't take my word for it. Go look at the FE forum and Fe Power Forum.  There are several threads.  Even some of the thin deck surfaces on Chinese FE cylinder heads sold under the PRW name and others.  Many of the FE power forum members are actually real racers. 
I am not trying to let the air out of your balloons, just giving you a heads up.

This is true but what was being discussed was a fatigue failure level using different materials.

I believe it is Compcams that suggested that the inertia of steels vs. aluminum in the case of rocker arms is virtually irrelevant?

Sharing information from real world use is very important. For one thing it gives what could be more accurate real world information that a manufacturer may have vested interest in concealing, marginalizing or unrealistically minimizing?

I have no way of doing scientific experiments to attempt verification of the results but one of the issues is that so many accept recognizable US "sellers" as manufacturers who have quality control over their products including the specification of the raw materials that go into them and in reality they don't since they are manufactured by sub-contractors that are not even US based.

Basic strength of materials considerations seems appropriate. One that can accurately state here without presenting data is that steel is stronger then aluminum.

As always, in selecting  a product all one can do is position themselves with a higher likeliness of intended success.

This is just a debate that will not end anytime soon.

You pay your moneys and you take your chances. It's as simple as that (and it isn't simple).   

[gt350hr]

    I wasn't aware the H/S went out of country , I thought they were still a Made in USA product. The common problem with off shore parts is the quality of design input / information. When the person creating the product is not aware of the dynamics a part operates under , it is difficult at best to make a reliable part. The Chinese did not "invent" H beam rods , they copied a Carrillo rod supplied from someone in the US looking for similar parts at a fraction of the cost. By the time the first ones were copied , Fred had been making them for well over 20 years and had continuously refined them. Your current Chinese copy from MANY sources is not made of the vacuum melt proprietary steel that Carrillos are made from and the machining quality does NOT compare , BUT they look the came and are over kill compared to stock rods in most cases.
  So progressing to rockers , the FE stainless offering looks to be an adaptation of a stud mount stainless rocker to a shaft mounted configuration. No attention ( because they don't know) was paid to the area subjected to higher stress loads  because of the threaded adjustor and intending angularity issues. So the rocker fails at a predictable ( by those familiar with the FE valve train dynamics) point. Adding a reinforcing rib on each side of this area would eliminate breakage and increase load capacity. No one has evidently asked for this revision so they continue to break.
    Randy

[2112]

I have had great luck with T&D on my SVO 385' engines, 565lbs spring pressure over the nose, .734" lift with 2.45" diameter S.S. Manley intakes and 1.94" Manley Inconel exhausts all living above 6,000 rpm

OEM FE application;

http://tdmach.com/product/fe-ford-332-428-o-e-m-style-single-shaft/

[Vcode]

    I wasn't aware the H/S went out of country , I thought they were still a Made in USA product.
    Randy

Their site states they made in the USA.

http://www.harlandsharp.com/About%20Us.html

[gt350hr]

 The Going Thing needs to revise his post then.

[shelbydoug]

I have had great luck with T&D on my SVO 385' engines, 565lbs spring pressure over the nose, .734" lift with 2.45" diameter S.S. Manley intakes and 1.94" Manley Inconel exhausts all living above 6,000 rpm

OEM FE application;

http://tdmach.com/product/fe-ford-332-428-o-e-m-style-single-shaft/

Those may be the best but I saw two Panteras with them where the bearings were completely shot at 1,000 miles.

Did they break? Absolutely not, just wore out the bearings.


I had a set of Ford Power Parts rockers and the adjusting nuts were offset from center. So there were four lefts and four rights on each head.

I didn't like the wave washer shims for the aluminum spacers they were delivered with.

They had bronze bushings to ride the shafts rather then bearings.

You NEED to use custom length push rods with them if you are using the cup end push rods.

Clearance to the arm from the cup edge is very close and the geometry needs to be just right.


I like the T&D versions better with bearings instead of bushings and internal oiling through the rocker arms themselves. It's better to have overkill in the valve train I think but the more complicated the assembly the more that can fail.

[The Going Thing]

Parts of the Harland Sharp are made in the US. Not the forging. I suppose that should have been specified.  Information provided via the customer their service ARP makes the adjusters.  T&D would have really been the way to go, and most on the FE forum who are running radical profiles and lifts as 2112 mentioned run the T&D or Jessel.  I am only at about 5.90 lift on the exhaust side of the equation, and 244@.50. Had I not retained power brakes I would have also ran a different cam. 

[shelbydoug]

    I wasn't aware the H/S went out of country , I thought they were still a Made in USA product.
    Randy

Their site states they made in the USA.

http://www.harlandsharp.com/About%20Us.html

Assembled in the US and Made in the US is not the same.

I remember the story of the M1 Abrams tanks. The turrets were being cast in Japan of a titanium alloy.

The process necessary was not allowed by the EPA. That tank WAS  assembled in the US though, so I guess you could say it was made here?


Being made overseas is not necessarily a bad thing but often is. There was the issue of the grade 8 bolts being made in China of an alloy of a grade 3 bolt but clearly marked 8.


I went through something like this with Center Force clutches. The COMPONENTS were coming from "third world countries" and being assembled in Mexico.

I was having issues with the hub that sits over the input shaft splitting.

My guy there is Gene. Gene "The Dick". Need further explanation?

The last disc cost me $125 UNDER WARRANTY and they charged me for the shipping.

Corporations suck. They are just in existence to protect their OWN incompetence.


A recent exception for me was Forge in the UK. Seems their "guaranteed for life" turbo intercooler really was. They, get this, didn't have any in stock, made one for ME THE SAME DAY and OVERNIGHTED it from the UK, UPS Blue Label.

ALL AT THEIR EXPENSE and they apologized for the failure. Made the  new one with thicker materials and bigger welds. I literally had it by 4pm the next day. Absolutely amazing. They keep their word.

Now why should I need to replace an intercooler? Well you should ask!

[gt350hr]

   Gene Humrich is a DICK , you should be dealing with Michael Hays.

    "Most" aluminum roller rockers are made from "extruded bar stock"  that is 6-8' lengths and cut into individual pieces reducing machining time. I know this from past involvement in the industry. I would be surprised ( again) if it was cheaper to import that material than buy it here in the states. H/S has come a long way in the last 35 years. Back then they had a serious problem with runout on the roller tip. They also were limited on spring pressure and broke at the same place as the "modern" stainless versions do.
   Needle bearings ( Like T&D and Jessel use) are not as "street friendly" as bronze bushings are. This is no different than a solid roller lifter where "lash" is involved along with long mileage. Bushings are the way to go .
     Randy

[shelbydoug]

I've only used two sets of Harland Sharps.

One on my Pantera w/351c and one in my 428.

I thought both designs were a bit dated and the Cleveland wouldn't keep adjustment so I "diagnosed" that as bending or flexing of the arm itself and went with a set of Compcam steel.

I would say that I have no issues per se with H/S but they seem dated. Little features on rockers now seem very important?

I like the internal oiling of the T&D on the rockers but then again I like little things like the oil drip tabs inside the covers of the Boss 302. You CAN use them with roller rockers but you need to trim the length and screw around with them and the lock nut lengths until you get them to fit.


Experience on items like these to me is irreplaceable. When you stray into the aftermarket, it can be walking on the "Frontier" alone and there are so many little things that can go wrong that can kill you.

I appreciate you sharing your expertise, regardless of how you got it, on technical subjects.