What would be a good upgrade from the stock ones I am using now?Aluminum, steel,billet? Any to avoid? Running Comp pro magnum rocker arms and will have about 350 lbs. open pressure.

I bought the Mancini ones for my small block. They are ultra beefy but the studs that come with them are pretty lame, i don't think a single one of them was straight and they could have been a little longer for my Edelbrock heads and Erson Rocker setup. But they worked and have lots of miles on them.

http://www.billetracingparts.com/Mopar%20Rocker%20Hold%20Downs.html

got a couple sets of these in use...

I used the parts from Mancini.The studs were fine. 440 engine.

Which motor size and brand and type heads ? I've used the stock stamp steel OEM holdowns and bolts on many BB and SB Mopar V8 bracket motors with similar valve spring pressures up to 7000 RPM If your going for the best holdowns now I would go with steel instead of aluminum due to the rocker shafts being steel so they have similar expansion rates as the motor heats up and no change of tension on the shafts at the holdowns Studs and nuts with a good quality harden flat steel washers under the nuts between the holdowns are better than bolts also

Cab, he'll be running a 470 w/Edelbrock RPMs.

Well it isn't that easy since the width depends on the rocker arms. I prefer the steel hold downs made from hex stock like the ones that Hughes and Harland sell but no guarantee that anything will work right out of the box. Be prepared to shim or machine the parts to fit.

Thanks for the bump Bubby.Andy:Narrowing or shimming won't be a problem.Just didn't want to start with a bad design.

I bought the ones hughes sells for my big block. Don't buy them if you're going to run solid spacers/shims, they fit on the stud pretty sloppy and you have to reset them all up every time you take the rockers off. Ask me how I know, I should just run spacer springs and be done with it

These, along with the corresponding geometry correction.

Was considering looking into those. I will have to wait until I get the old engine out and get them on the new shortblock to measure for them though.

Mike...Have you ever considered being a Moparts sponsor?

Yes I have ,Ted. There always seems to be something expensive that takes priority though. Can you PM me with some details, prices, etc.?

I will pm you.

I used the MP AL rocker hold downs some years ago. The engine is a 496B with comp cast steel alloy rockers. From memory, I used an ARP fastener kit including rocker studs that has worked fine.

I did have to have a little material milled of the sides of the hold downs to create clearance and line up rockers and valves with shims. I also wanted to make sure I had at least one shim between the steel rocker and AL hold down to prevent excess wear. With that it has worked great through some hard miles and one freshen.

I used the Hughes ones that Mancini sells and they work perfect

Gus

Gus,
Where did you get the spacer rings from?

I built my own out of 1018 steel. Mine wrap the shaft about 200°. This keeps them from falling off the shaft when not bolted to the head. Just a personal preference. I used ARP studs but came up with 5/16-18 flange nuts that use a 9/16 wrench size to put more surface on the contact area.

I'm lucky enough to live near the Harlan Sharp machine shop and I just took one of my heads over there and we set my rockers up on their bench. I think you could get the same ones from Mancini Racing though.
Gus

The hold downs from Harland are the beefiest ones I've come across. If these will fit with your rocker arms then I'd go this way. Buy a set of rocker shaft studs from ARP and you'll be set.