Scorpion roller rockers

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ProPower engines
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Scorpion roller rockers

Post by ProPower engines » Tue Aug 08, 2017 1:30 am

Hey guys '
Have you seen any different levels of scorpion rockers.
The race rockers look like they have a nicely machined trunnion that is retained in the body with a snap ring.
I recently seens a rash of valve train failures with what looks like a cheap copy or a more entry level rocker that has no retaining method of positively centering the trunnion and the roller bearings are just pressed into the body and totally relies on the poly lock nut to locate the rocker on the stud. These are 3/8" stud rockers and the poly nut is too short to allow full movement of the rocker without the poly nuy digging into the upper part ot the slot for the poly nut to ride in.

I have several engines that were imported from a builder in the USA to several local marine shops and they are all failing the valve train and I have been asked to figure out why and what is wrong with the component choices.

All I can say at this time is it uses what appears to be an aftermarket off shore 906 head casting with threaded rocker stud boss's and these guided rockers with no G/plates but the pushrods used are about .150 longer then needed as the rocker would really bind the poly nut if they are the right length.
The valve spring at max lift is the shape of a banana bowed bad to one side. Stock type spring installed at 1.680 which is on the tight side of stock vortec spec of 1.680 to 1.700. but it appears the spring seats are no 90 degrees to the stem for them to bow that bad and the spring is stacked solid on the side not bowed.

But any help to ID the rockers or the heads will help me investigate and solve the issues.

The issues being suffered are bent pushrods as they are just a 89cent stock GM std roller block pushrod with welded ball ends.
Broken rocker studs 3/8" of an unknown brand.
Bent valves both int+exh because of the guided rockers jumping off the valve tip.
And the funny thing is the builder can't even tell what the lobe lift on the cam is. While it was checked there is little to no spring clearance for what they are using at this time.

If anyone can ID the parts origin or quality mentioned your help will be eternally appreciated

Dave C
Real Race Cars Don't Have Doors

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Re: Scorpion roller rockers

Post by mag2555 » Tue Aug 08, 2017 6:13 am

In regards to a buddy's Pontiac motor using that brand riviera there 1.65 rocker checks in at more like 1.78 and needs a far longer push rod then Harland sharp brand 1.65 rockers that check in at 1.72.

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Re: Scorpion roller rockers

Post by Newold1 » Tue Aug 08, 2017 10:17 am

According to Scorpion, all their rockers are machined and assembled in the USA. I believe you may be comparing the standard width body rockers to the narrow body rockers. They obviously eliminated the snap ring on the narrow body to decrease the width of these narrow body rockers. There don't seem to be any complaints around the users that they are failing, are you seeing a failure problem?

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Re: Scorpion roller rockers

Post by cstraub » Tue Aug 08, 2017 11:52 am

ProPower engines wrote:Hey guys '
Have you seen any different levels of scorpion rockers.
The race rockers look like they have a nicely machined trunnion that is retained in the body with a snap ring.
I recently seens a rash of valve train failures with what looks like a cheap copy or a more entry level rocker that has no retaining method of positively centering the trunnion and the roller bearings are just pressed into the body and totally relies on the poly lock nut to locate the rocker on the stud. These are 3/8" stud rockers and the poly nut is too short to allow full movement of the rocker without the poly nuy digging into the upper part ot the slot for the poly nut to ride in.

I have several engines that were imported from a builder in the USA to several local marine shops and they are all failing the valve train and I have been asked to figure out why and what is wrong with the component choices.

All I can say at this time is it uses what appears to be an aftermarket off shore 906 head casting with threaded rocker stud boss's and these guided rockers with no G/plates but the pushrods used are about .150 longer then needed as the rocker would really bind the poly nut if they are the right length.
The valve spring at max lift is the shape of a banana bowed bad to one side. Stock type spring installed at 1.680 which is on the tight side of stock vortec spec of 1.680 to 1.700. but it appears the spring seats are no 90 degrees to the stem for them to bow that bad and the spring is stacked solid on the side not bowed.

But any help to ID the rockers or the heads will help me investigate and solve the issues.

The issues being suffered are bent pushrods as they are just a 89cent stock GM std roller block pushrod with welded ball ends.
Broken rocker studs 3/8" of an unknown brand.
Bent valves both int+exh because of the guided rockers jumping off the valve tip.
And the funny thing is the builder can't even tell what the lobe lift on the cam is. While it was checked there is little to no spring clearance for what they are using at this time.

If anyone can ID the parts origin or quality mentioned your help will be eternally appreciated

Dave C
Company had been in financial bad shape for last 3 years. New owner bought it in late 2016.
Chris Straub
Performance Mfg.
http://www.straubtechnologies.com
www.distributorgears.com

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Re: Scorpion roller rockers

Post by F-BIRD'88 » Tue Aug 08, 2017 11:53 am

A genuine Scorpion rocker arm will have the Scorpion etched in the top
and the ratio. They do make same rockers for others like Howards and Summit etc.
The Howards are also etched with the brand.

This stuff does not sound like Scorpion stuff. Sounds like all cheap off shore stuff.
Scorpion Performance is in Florida.
If it is actually their product they will want to know about it,
Their stuff is lifetime warrantied. They do not cover stuff that is not theirs at all.
Lots of copy s around.

You never hear of issues with the Scorpion or the Howards or the Summit stuff.
They make a ton of this stuff so......

Company had been in financial bad shape for last 3 years. New owner bought it in late 2016

This is what happens when you have to compete against cheap crap off shore
stuff made of chinesium (ham sandwiches).

Is there a Scorpion etched on your rockers?

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Re: Scorpion roller rockers

Post by ProPower engines » Tue Aug 08, 2017 12:30 pm

Yes it has the logo etched in the tip of the rocker but I had never seen the cheaper version without the snap ring to hold it together.
Still doing some checking. Will keep you all posted with results.

Dave C
Real Race Cars Don't Have Doors

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Re: Scorpion roller rockers

Post by Newold1 » Tue Aug 08, 2017 6:22 pm

If you are talking about the narrow body rockers from Scorpion they are used for the Vortec 904 type heads. I have always been told not to use guide plates and self-aligning rockers at the same time on these heads as the center to center on the valves is not quite the same as other small block 23 degree heads and can cause side loads and push rod, rocker and valve issues. If the heads are offshore Vortec iron heads and not GM part numbers there could be some other fitment, measurement and machining issues. I am curious if anybody else is having problems with the Scorpion narrow body rockers?

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Re: Scorpion roller rockers

Post by billet » Tue Aug 08, 2017 11:59 pm

ProPower engines wrote:Yes it has the logo etched in the tip of the rocker but I had never seen the cheaper version without the snap ring to hold it together.
Still doing some checking. Will keep you all posted with results.

Dave C
Dave I know the son of one of the new owners really well. If you want to send some pictures or whatever to me, I can forward them to him or get you a contact number.

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Re: Scorpion roller rockers

Post by ProPower engines » Wed Aug 09, 2017 1:07 am

If you can PM me the contact info that would be the best way to do it.
That way there is no confusion or possible finger pointing :D
Real Race Cars Don't Have Doors

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Re: Scorpion roller rockers

Post by Geoff2 » Wed Aug 09, 2017 5:55 am

I have seen pictures of Scorpion alum rockers used on a Pontiac that had started to crack around the axle of the roller tip. Spring pressures were not excessive.

Have also seen Scorpion rockers where the anodising around the bottom of the trunnion had to to fret & flake. Some idiot told the OP 'not to worry about it'...

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Re: Scorpion roller rockers

Post by midnightbluS10 » Wed Aug 09, 2017 6:43 am

F-BIRD'88 wrote:A genuine Scorpion rocker arm will have the Scorpion etched in the top
and the ratio. They do make same rockers for others like Howards and Summit etc.
The Howards are also etched with the brand.

This stuff does not sound like Scorpion stuff. Sounds like all cheap off shore stuff.
Scorpion Performance is in Florida.
If it is actually their product they will want to know about it,
Their stuff is lifetime warrantied. They do not cover stuff that is not theirs at all.
Lots of copy s around.

You never hear of issues with the Scorpion or the Howards or the Summit stuff.
They make a ton of this stuff so......

Company had been in financial bad shape for last 3 years. New owner bought it in late 2016

This is what happens when you have to compete against cheap crap off shore
stuff made of chinesium (ham sandwiches).

Is there a Scorpion etched on your rockers?
Never hear of issues with Scorpion? What rock have you been under? I've seen talk of it at almost every performance-oriented forum I visit. There's always someone with issues. Whether it be a broken rocker arm itself, anodizing flaking, or any number of other issues.


I've seen more pics similar to this than I can count

Image

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Re: Scorpion roller rockers

Post by F-BIRD'88 » Wed Aug 09, 2017 1:11 pm

Now post the link to the forum thread that that picture refers to so the mechanical pounding shock that that rocker was subjected to is exposed.
Was there ever a warranty claim made on this rocker arm set?

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Re: Scorpion roller rockers

Post by Newold1 » Wed Aug 09, 2017 6:53 pm

Let's be real. There are idiots by the boat loads on many forums who can and do beat the shit out of and break perfectly good quality parts and then throw the blame at the manufacturer! Send these guys some mirrors and tell them to stand in front for a long time and observe what a buck passer looks like! I would almost bet good money that on that Scorpion rocker in that pic had either a valve lash improperly set, bad valve spring operation or a valve dancing off the top of a piston. Obviously a bad part can show up in any good race part manufacturer, but if they show up in great numbers with regularity you'll usually find that manufacturer will run and hide from the problem. How did Scorpion handle or look into this failure.

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Re: Scorpion roller rockers

Post by MadBill » Wed Aug 09, 2017 8:48 pm

There does look to be a lot of wear on the polylock mating surface, perhaps indicative of loose lash...
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Re: Scorpion roller rockers

Post by statsystems » Thu Aug 10, 2017 4:16 pm

Who was it that said some guys can break a bowling ball in a sand box with no tools? Or something similar. I thought it was Smokey Yunik. Then I thought again and was thinking Duntov. Then I thought some more a decided I was just guessing.

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