360 valve train

[jusglazin]

I need advice on a non magnum 360 build. So far the engine is bored .30, stock cast crank, Edelbrock performer RPM heads and Comp extreme retrofit roller cam. The cam has Duration 268/276, Lift .535/.531. I have a set of no name brand roller tip aluminum rockers and with a test fit I can see they contact the springs on about all valves. I need to buy another set so My question is with this cam must I use adjustable rockers or can I get away with the stock setup and correct length pushrods? I don't want to spend anymore than necessary. All recommendations welcomed!

 

[RustyRatRod]

You need adjustable rockers. I would hawk Ebay for a set of the iron 273 rockers. With some good adjusters they are bullitproof.

Here's some.

http://www.ebay.com/itm/mopar-ducti...Parts_Accessories&hash=item1c3196921b&vxp=mtr

 

[jusglazin]

Thanks ill check those out. Here are pics of the junk that came with the engine. Looks like they were rubbing before. Wonder why the guy sold it all so cheap!

 

[Budnicks]

with replacement aluminum heads & thicker head gaskets, make sure you have the proper length of push rods too... no matter what rocker you choose to use... Also any more than 3 full threads of the adjuster sticking out of the bottom side of the rockers, when you have the proper lifter pre-load or valve lash, if you do, then you probably have too short of push rods... Cheap fix, you can always take a peanut grinder or Dremel tool with a carbide tip to the areas where you have rocker to valve spring or retainer contact, 0.20-0.030" is plenty of clearance at the most likely max contact points, make sure you don't go too far, keep the area smooth not just gouge it out... IMHFO it's a very common issue, especially with over sized valve springs & retainers or longer valves & higher installed heights, especially with big fat aluminum roller rockers, just make sure you clean them really well before reinstalling them....

 

[jusglazin]

Thank you for the help Budnick. I purchased a adjustable pushrod tool so I can measure once I determine if These can be used or not. The other issue I see with these is the roller tips are are way over to the outside edge of the valve stem. This is without the pushrods installed. Is there a way to center the tips on valves? Will shims help this?

 

[Budnicks]

hold downs, spacers & shims, then trial & error, on & off several times, before you get them right, sometime the aftermarket hold downs & studs, spacers & shim for the shafts are better suited for keeping the rockers centered better, make sure when you move them, you make sure you have plenty of clearance between the push-rods & the intake ports etc. or anywhere else make sure they will clear everywhere thru the whole range of lift with out any interference/rubbing.... sometimes just lash caps will do the trick too... ever engine is different, it really depends on camshaft base circle sizes, deck height, gasket thicknesses, head surfacing/milling, rocker shaft pedestal stand height etc., allot of places it can make the push rod length change...

 

[jusglazin]

Thanks again. These rockers are also missing the large spacers between each arm. Can you help me identify what brand they are? I can't find any numbers on them but the look like Harland sharps I see on summit for 600 bucks. I want to try ordering shims, spacers and hold downs at the same time. Are the spacers specific to the brand. Check out the pics and let me know what you think these may be.

 

[Budnicks]

By those photos I can't 100% accurately say who's rockers they are, I think Comps are a red anodized color too... Harland Sharpe's are full rollers & have full needle/pin rollers on the shaft/trunnions too, they look like the color of the Harland Sharpe's, sometimes you need to add some spacing between the rockers that require you grind a slight bit off the hold down bolts concave spacer/washer then add an extra shim in between the rockers/roller tips that are over to one side or other of the valve tips, as long as they aren't like half way on the valve tip, you could also add lash caps too, if necessary, that requires a shorter push-rod usually too... but as long as a majority of the roller tip is on/over the valve stem & not excessive hang over, it is probably OK, if you move any of the rockers, make sure to check rocker to valve spring/retainer & push rod clearance again too...

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maybe call the guys at Mancini Racing, they are really good head & tech guys, call the Tech Support line @ 1-586-790-4100

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some rocker usually not rollers thou, have just some springs on the shafts between the rockers, then the steel or aluminum spacers only on the hold down bolts/studs... all the one shown below are many different Big Block versions, but give you an idea of different styles of rockers & spacers even a sets of shaft/shims for spacing the shafts "up" some if needed, after installing lash caps, milling heads, minor push-rod length corrections, or rocker clearances etc.