[Banditogto]

Well, I'm stumped. I tore the motor down expecting to find bits and pieces and the missing needle bearlings, but I found nothing out of the ordinary. Bottom of the oil pan was clean other than the thin black layer of break in lube. I also cut open the filter which I thought for sure I'd find something. Wrong. Nothing there either. I guess this is a good thing, but where could the missing needle bearings have gone? Am I missing something? As usual, any help is greatly appreciated. Thanks.

[Ken -Ace- Brewer]

I recomend only using the SS Roller Rockers on Solid Roller Cams. John Ageles runs PRW's. He did THE EXACT same thing with his Aluminums. Changed to the PRW SS Rockers and is still running them today. But John is running SICK valve spring pressure. Up in the 450 lbs area CLOSED!!

I only Recomend the PRW Stainless Steel Rockers on Solid Roller Cams. The spring pressure of a Solid Roller is just to much for the Aluminums. But of course this is only my experience and opinion.

Ace

[Banditogto]

Thank you Ace. You're the second person that has said that same thing. I guess I've learned a valuable lesson, and I hope others will learn from this post and not make the same mistake that I have made. DO NOT RUN ALUMINUM ROCKERS WITH A SOLID ROLLER CAM. I am thankful that it appears that this did not cause any serious damage, other than two of the studs are a bit chewed on, and I will be putting the motor back together and hopefully be racing again soon. Thanks to all for your thoughts and input. Drag on my Pontiac brothers.

[fasteddy]

Check in the oil troughs in the cylinder heads for the bearings. That is where the lash caps end up anyway. Ask me how I know. The needles may have made it to the valley as well. If you have a mega brace, you might find them there.

[PONTIAC DUDE]

Originally Posted by Banditogto

Thank you Ace. You're the second person that has said that same thing. I guess I've learned a valuable lesson, and I hope others will learn from this post and not make the same mistake that I have made. DO NOT RUN ALUMINUM ROCKERS WITH A SOLID ROLLER CAM. I am thankful that it appears that this did not cause any serious damage, other than two of the studs are a bit chewed on, and I will be putting the motor back together and hopefully be racing again soon. Thanks to all for your thoughts and input. Drag on my Pontiac brothers.

This is a wrong statement. DO NOT RUN ALUMINUM ROCKERS WITH A SOLID ROLLER CAM. Nothing wrong with Aluminum rockers and roller cams. Have been doing it for 35 plus years and NOT ONE ISSUE other then a pin coming out of a well used set of Crane rockers. Fords, Mopars, Chevies, Caddy, Olds, the list goes on. And hundreds of short track Late model engines with thousands of laps.

There is only 2 reasons your having an issue.

#1: there is something wrong with your valvetrain or geometry

#2: The quality of the Brand or casting of the rocker isn't up to what you are trying to do.

[TinjunTribe]

Originally Posted by PONTIAC DUDE

#2: The quality of the Brand or casting of the rocker isn't up to what you are trying to do.

PRW are Extruded then machined are they not? I was told they were, as I did NOT want cast aluminum rockers.

[Ron H]

Originally Posted by tiacguy

6061 is not aircraft grade aluminum. 7000 series are. From what I can see its not the aluminum that failed. Its the steel fulcrums. Id say the rockers arent rated for your spring preasures.

Aircraft Alloys and Aerospace Metal Grade Products

- Aluminum Grades: 2011-T3, 2219, 6061-T6, 7075-T6, 7075-T6, 7075-7351, 2024-T6, 2024-T4, 7050 Aluminum tubing

Sorry mate, 6061 T-6 is an aircraft grade.

[PONTIAC DUDE]

To follow up on this. PRW rockers.
Apparently this isn't a Pontiac only issue. Was up on Yellow bullet and see that others with other make engines are experiencing the same issues and breaking points.

orangecrush 357
Junior Member
Spooled up

Join Date: Jun 2009
Location: new carlisle,ohio
Posts: 114

Default Re: Which companies to never buy from?
hurst (after waiting 3 ****ing months for a shifter handle i cancelled)
prw (roller rocker falcrums break on a mild street engine)

[Banditogto]

Thanks for sharing the info Dude. Just an update on my situatation with these. I contacted Dave & Marcel at SD Performance and informed them about what had happened, being I had originally purchased the rockers from them. They were very helpful and offered up possible causes and solutions as to why this may have happened. They suggested that I go with PRW's stainless rockers. So I sent them my broken aluminum one's, and they sent me the stainless one's at minimal cost. I have yet to install them, but I had planned to give them a try. Anyone have any experience using these?

[tiacguy]

Ok Ron if you want to prove a point 6061-t6 may be concidered an aerospace alloy. But its not HARD alloy. Its only medium grade. Its used for a lot of stuff because its easy to machine and has a nice surface. 6262 is what is used for nuts and bolts and their only grade two. It does not have the strength of the 7000 series alloys. Thats the point isnt it? Maybe Im all wet here Ive only been extruding this stuff for 29 years. There are so many propriortary alloys out there who knows what these rockers are made out of. Do you? Extruded is always stonger than cast. Good luck getting your car combo straightened out.

[PONTIAC DUDE]

Question:
Is extruded as good or better as Forged in a rocker?

[tiacguy]

Dude Simply put cast is multen aluminum poored into a mold. There are ways of casting that can inhance their strenght Vaccum cast etc.but it will never be as strong as a forging or extrusion by nature of the proccess. An extrusion is proformed by heating a solid billet of aluminum and forcing it through a heated die to produce the piece. Which is a direct press method or a die is pressed through a heated billet which is an indirect method.The indirect produces a much smaller,finner grain which gives aluminum much better strenght. Most of your oil filters,pop cans,fire exstinguishers etc are made from rod produced on an indirect press than forged. The aluminum never liquifies but the process does change the grain structure dramaticly over a casting. A forging is the best method of controling gain structure. An extrusion can have a very cource misplaced grain structure. Heat treating helps but you still wont have a forging. In a Forging a piece of extruded plate its heated and then forged under extreme pressure into a product billet blank which produces better grain structure. And is then machined into its final state. In an extruded rocker the grain will be cource,straight as it was when it was extruded. A forged rocker will have much smaller scattered grain which makes it stronger. As an example. If you were going to make a billet cylinder head you wouldnt machine it out of an aluminum casting. You woud start with a piece of 8x8 extruded bar stock. Hope this helps Scott.

[GTOLou]

Don't like to hear that the chinese rockers are a question mark for mild street engines...

[Ron]

Get them installed.....Summit Series races this weekend at Fontana. Bill and I will be parked toward the last turn out. Go to the track entrance and look half right and we should be in that area...close to the fence. I'm parking tomorrow and Bill will be out early on Saturday to park and tech.

[Banditogto]

Hey Ron,

Sure wish I could, but the motor and trans are still out of the car. I pulled it to search for the needle bearings from the broken rockers, and needed to bump up the stall on my converter. Should be ready to put it back in within the next week or so. When will you & Bill be racing again after Summit?

JR.

[Ron]

Nothing on our schedules till the ET finals in October....if we make the team. Bill will proably make it but I've experienced lots of breakage this year and I'm in the toilet points wise. Other than that Bill and I will go to Speedworld for Hangover's. Went last year and had a blast.

[Overkillphil]

Anyone know of a quality made roller rocker that will directly replace these PRW's without having to change to different length pushrods...again?

My instincts told me to spend the extra money on the Scorpions at the time but I put my trust in the supplier.

[PONTIAC DUDE]

Originally Posted by tiacguy

Dude Simply put cast is multen aluminum poored into a mold. There are ways of casting that can inhance their strenght Vaccum cast etc.but it will never be as strong as a forging or extrusion by nature of the proccess. An extrusion is proformed by heating a solid billet of aluminum and forcing it through a heated die to produce the piece. Which is a direct press method or a die is pressed through a heated billet which is an indirect method.The indirect produces a much smaller,finner grain which gives aluminum much better strenght. Most of your oil filters,pop cans,fire exstinguishers etc are made from rod produced on an indirect press than forged. The aluminum never liquifies but the process does change the grain structure dramaticly over a casting. A forging is the best method of controling gain structure. An extrusion can have a very cource misplaced grain structure. Heat treating helps but you still wont have a forging. In a Forging a piece of extruded plate its heated and then forged under extreme pressure into a product billet blank which produces better grain structure. And is then machined into its final state. In an extruded rocker the grain will be cource,straight as it was when it was extruded. A forged rocker will have much smaller scattered grain which makes it stronger. As an example. If you were going to make a billet cylinder head you wouldnt machine it out of an aluminum casting. You woud start with a piece of 8x8 extruded bar stock. Hope this helps Scott.

Thanks for the info. I'll stick with my Harland Sharp (never had a failure yet in 30 years) for rollers and upper end builds and my other 'forged' cheaper brand for street/strip use.

[PONTIAC DUDE]

Originally Posted by tiacguy

Dude Simply put cast is multen aluminum poored into a mold. There are ways of casting that can inhance their strenght Vaccum cast etc.but it will never be as strong as a forging or extrusion by nature of the proccess. An extrusion is proformed by heating a solid billet of aluminum and forcing it through a heated die to produce the piece. Which is a direct press method or a die is pressed through a heated billet which is an indirect method.The indirect produces a much smaller,finner grain which gives aluminum much better strength. Most of your oil filters,pop cans,fire exstinguishers etc are made from rod produced on an indirect press than forged. The aluminum never liquidfies but the process does change the grain structure dramaticly over a casting. A forging is the best method of controlling grain structure. An extrusion can have a very course misplaced grain structure. Heat treating helps but you still wont have a forging. In a Forging a piece of extruded plate its heated and then forged under extreme pressure into a product billet blank which produces better grain structure. And is then machined into its final state. In an extruded rocker the grain will be cource,straight as it was when it was extruded. A forged rocker will have much smaller scattered grain which makes it stronger. As an example. If you were going to make a billet cylinder head you wouldn't machine it out of an aluminum casting. You would start with a piece of 8x8 extruded bar stock. Hope this helps Scott.

Thanks for the info. I'll stick with my Harland Sharp (never had a failure yet in 30 years) for rollers and upper end builds and my other 'forged' cheaper brand for street/strip use.