[Murf'sDad]

Hi Guys:

I going with roller rockers when I do the roller cam. I had considered stainless Crowers because I'll be using Crower springs and lifters. But they are very pricey. Scorpions have been recommended and I may go that way. (I've got GM (Crane) aluminum roller rockers on my LT1 SS Impala and they work well.) I see that KRE has PRW stainless roller rockers that look a lot like the Crowers and they are only $5 more than the Scorpion aluminum rockers. I don't know this brand. Anyone used them or have any feedback on them?

Thanx, Stewart

[TransAm525]

I have the Scorpions on my 78 Trans Am and am very happy with them. They are very high quality and the price is perfect. So far they have over a year of daily driving use on them with no problems. A lot of people also like the Harland Sharps, but they don't have a lot of material on the top, which to me is just asking for a failure at some point, but to each his own. Unless you're going to run very high spring pressures, any cast aluminum roller rocker will work. The only difference between the Crane and Scorpion rockers is the Cranes are forged aluminum (and overpriced) and the Scorpions are cast aluminum. Whatever you do, don't purchase the Comp Cams roller tip rockers. They are junk and most of the friction is at the fulcrum point, not the tip, so they will give you virtually no gain.

[Murf'sDad]

I'll be running about 450# - 500# OTN pressure. That is why I was looking at the stainless rockers rather than the aluminum ones.

Any one used the PRW stainless rockers?

Stewart

[GTOLou]

Anyone used these?:

http://store.summitracing.com/partde...6&autoview=sku







I've used Scorpions - happy with those.




Actually I have a set of the 1.6 ratio rockers from butler in use for about 1 1/2 to 2 years. Working fine - they are at the bottom of the page. Very cheap.

http://www.jbp-pontiac.com/products/...rms&Comp..html



I've used both with HR cams - no SRoller use...

[440GP69]

The PRW are good, my favorite all time chromoly rocker is Crower stainless steel enduro rockers 1.65 ratio, get them from ACE at PPR

[gtofreek]

I would definately stick with the stainless steel rockers. I have seen aluminum rockers break at those spring pressures. Also, most SS rockers are lighter on the valve end than aluminum rockers so there is a weight savings also on the valve end of the program.

[440GP69]

SS also is more ridged, is rebuildable and the crowers on my paps 1600hp blown alchohol engine have been going for 6 seasons with 300lbs seat pressure and 1,050lbs open pressure! pretty much will last forever on a street engine IMO

[b-man]

Bite the bullet and buy the Crower stainless rockers.

I feel that it's always better to buy the best and never have to worry.

Got mine from Ace at PPR, he was even kind enough to swap a set of 1.5s for some 1.65s a couple years later after I changed my mind (still new in the box).

Many years before that I bought a set of Norris stainless 1.65s from Ken Crocie (H-O Racing), they're still going strong on my street 455 after a decade of bracket racing.

[Old Man Taylor]

I run the Crower Stainless roller rockers on my streetcar.

[Geoff]

Two things you can be sure of:

[1] Steel or s/steel rockers will NOT fail unless stressed beyond their safe working load.

[2] Alum rockers WILL fail from constant flexing, but it is impossible to predict when or how long it will take.

[Steve C.]

There are differances in types of aluminium and construction methods. This from Crane Cams....


For many years, it was thought that aluminum roller rocker arms could not be used on a daily driven street car. The major reasons were that the aluminum would eventually become brittle and break and that a roller tip would not allow the valve(s) to rotate, causing excessive/premature wear of said valve. While these may have been legitimate concerns at the time, both have since been disproven. Contemporary aluminum roller rocker arms are made from various alloys, which have dramatically improved their strength and longevity, making them more than adequate for continuous use.

( You will find a similar message from all the major rocker arm manufactures )

[gtofreek]

I've seen aluminum rockers break more than once with only 350 lbs. open pressure. And with very few miles to boot. T&D's and Jesel's are good for high spring pressures, but most stud mount aluminum rockers are iffy when using spring pressures over 350 lbs. Especially cast aluminum rockers. They are only good for bone stock applications as far as I'm concerned.

[pastry_chef]

Originally Posted by gtofreek

most stud mount aluminum rockers are iffy when using spring pressures over 350 lbs. Especially cast aluminum rockers. They are only good for bone stock applications as far as I'm concerned.

Harland Sharp's will handle anything until you NEED T&D or Jesel shafts.

http://www.rehermorrison.com/superSeries/540Start.htm

http://www.shafiroff.com/pro/565_1000.asp

http://www.harlandsharp.com/

Ask Jim Hand or countless others how their Harland's have served them.

[NO67GTO]

I have JBP alu 1.5 roller rockers on my street strip 455 w/ 96 heads for 5 years and have seen no sign of fatgue or stress. Pivots still roll free and smooth. I just have a hyd cam no roller or crazy spring pressures. Good luck.

[1971GTO]

On this subject, I want to put 1.6 roller Scorpions on my stock 455HO. Will they go under stock valve covers?

[b-man]

Originally Posted by 1971GTO

On this subject, I want to put 1.6 roller Scorpions on my stock 455HO. Will they go under stock valve covers?

With some thicker valve cover gaskets they'll fit.

Butler performance sells a gasket that is 5/16" thick. You'll need some longer bolts to hold the cover down with the thicker gaskets.

[Murf'sDad]

Would it be a safe assumption that PRW's are made "off-shore". I found their website and they don't mention specifically where their products are made.

I did notice that the PRW rockers are made of 15-5 stainless and the Crower rockers are made of 17-4. That would would make the Crowers better because of the slightly higher yield strength and slightly less elongation %.

Notwithstanding all of the suggestions and comments about going with Crower (my first choice), are the PRW's inherently inferior? After all there is a $200 difference in price.

Stewart

[jusjay]

PRW have had quality issues in the past. Soft rollers, rollers position too high allowing the rocker to ride on the spring caps, weak fulcrum and the supplied polylocks are prone to back out or just break. They are "off shore". The company has had to sent back or get credit for 100's of sets.

[Murf'sDad]

OK, this is relevant info. I hadn't heard of problems because I wasn't familiar with PRW products. Have these problems been corrected or are PRW SS rockers still having QC problems?

Thanx jusjay.

Stewart

[71firebird400]

If Dave B is selling them I'd personally have no problem using them. Like you, I have yet to see any real feedback on those rockers.