This was discussed a few years ago over at Moparts.org forums
where there are several Chrysler engineers and guys who work
for Mopar Performance retail sellers. All confirm you can bolt the
Viper V10 rocker arms down, but you get less ratio, and the Viper
rocker arm will 'wipe' the valve stem tip off center and cause wear.

Call the Mopar Performance hot line in the catalog and ask
they will tell you the same thing.

Don't believe this and want to measure for yourself?
Pull the valve cover and stick a dial indicator on the two ends of the rocker arm...find the ratio for yourself.

The Magnum 5.2/5.9 cylinder head rocker arm geometry is the same as the Chevy small block v8, except for the stud mount diameter. You can confirm this by calling either Crane or Edelbrock.

 

If you have a full 1/16"( that's around .060) with the lifters pumped all the way up it's will definately play hell on your valves. I couldn't even imagine what that would sound like and how loud it would be. Just for the hell of it (since you already bought the rockers) you could get a 7.025 pushrod. Measure of course. Take the length ot thepushrod you have now and add whatever the slack is plus .060 for preload.Install it on the #1 exhaust valve, crank the motor (fuel and spark disabled) with the starterto bleed the preload down, and thenhand crank the motor watching the rocker and valve tipto see where it puts you. At tdc the rocker should be just a little off center on the tip towards the intakemanifold side. As you crank the motor it should move across the valve tip and end up a little off center towards the exhaust manifold side.

If that ends up right, wouldn't the ratio end up being the advertised ratio? I thought the ratio was based on the respective distances of the rocker tip and pushrod seat from the fulcrum. If the fulcrum to tip distance is too short or too long then it is what it is, but I have read about alot of people ( Dak's, Durango's, Rams, etc.) doing this. I would be interested to know.

Mopar hotline: 888-528-4364

 

They are for sale PM mefor the price I got them for near dealer cost?

 

like i have said before had them on my 95 no noise and no wear after the 6th oil change. I called the direct connection line before i installed and they told me that they would not even bolt up to the the magnum 5.2/5.9 head. I deal with the guys at chrysler a lot because of my job and i promise they dont have all the right answers...but hey this is coming from a guy who glued littel pieces of aluminum to his truck and says that a fastman tb is less effective than the stock. As for me im out i have can't handle hanks post any more he is full of crap and no real world info.

 

I bolted on a set about 9 months ago and noticed an instant increase in power. You cant tell me they don't work.

 

I don't always agree with HankL either,but, from perusing his posts on several forums, I can say that he is one well read, informed, and intelligent individual. He merely offered up some info that he has acquired through the Mopar community. That is no reason to blast him. This info is new to alot of us. Why not investigate it further. You, most of all, I would think would be especially concerned since you are running the Viper rockers. It could be that you noticed an increase in acceleration due to morelow end torque as a result of increased vacuum signal from having a lower ratio rocker installed. Why not let everyone chime in so you can make a informed decision as to whether or not the gain is worth the long (or short) term wear this mod may cause due to incorrect valvetrain geometry.

 

hmm, maybe ill be buying the damn 250 buck rockers after all[&:]

 

No one has to take my word for it.

The proof is right there on the engine's valvetrain.

It is easy to measure the ratio with a dial indicator.

It is easy to see if the tip of the rocker is centered on the valve stem.

If you mount both the factory Magnum rocker arm
and the Viper V10 rocker arm
on the same 5/16 stud
back to back the geometry should be clear.

I can't understand why someone would object
to calling and asking Mopar Performance
...but it is a free country.

Larry Shepard has had out two editions of his Magnum Engines book but does not say Viper V10 rocker arms have the right geometry.
Jim Szilagyi's 'How to Build Big-Inch Mopar Small Blocks' lists almost
a dozen rocker arms that will work with either factory Magnum or RT Cylinder heads...but says nothing about using Viper V10 arms.
Steve Dulcich wrote an article recently detailing how Chevy rocker arm geometry is the same as Magnums and had a table of parts...but no mention of V10 arms being right.

The guys on Moparts.org said they would bolt up but gave less ratio and would not center on the valve stem....they didn't say the engine would not run...in fact with less ratio the engine would feel 'torquey' in the lower rpms.

No one above volunteers that they measured everything and found a perfect fit.

Are you mad at me
{Shooting the Messager}
or are you mad because you didn't measure...
{Measure twice, Cut once}

 

I remember reading up on this "mod"a while back and seeing that HankL and TPSDODGE disaggreed on different threads, i guessed this day would come......

I agree with mopowar....... threads going back to '04 don't go into detail, just some guys who are not active any more.....it should be investigated further.

 

This mod is similar to another mod that can turn into a mess. The notorious 180 deg thermostat.
Some people could feel an improvement, others nothing, to others like me who got the CEL prize.
Now with viper rockers, they work for some and not for others.
And this makes me even hesitant to buy the Harland Sharps. Just because they worked for someone else is no guarantee they will work for everyone.
I hope this discussion continues to a resolution. Can anyone compare a HS rocker with a Viper to see of they are the same?