Roller rockers

[chev74]

On my mild 350, would simply replacing the mechanical rockers with roller rockers make a noticable difference? I have a set that was given to me, and was just thinking that if ireplaced them, would it be worth it. What are the pros/cons of this swap, if i choose to do so?

[71Dragtruck]

You wouldn't notice any performance gains, and they might not fit under stock height valve covers or clear the internal baffles, also if they are aluminum over time could stress crack but not likely with a mild setup. On the good they were free, and they will cause less valve tip wear and reduce some of the valvetrain heat caused by the stockers. The ratio will also be more consistant from rocker to rocker. So you decide if it's worth your time to change them or not.

[chev74]

hmmmmmmmmmmm....... probably not. May just use them on a future engine build....

thanks for the input

[Sweet72]

What brand/model are they?

[piecesparts]

Take it from someon that has the experience with a lower quality roller rocker install. The better ones will last longer and give a longer life to your engine. however, there is probably a good reason the items were given away, rather than sold.

[chev74]

im pretty sure they are Crane? they are at my parents so i cant honestly tell ya

[bryanw1968]

Crane should be o.k. Like mentioned earlier though it's not worth it to put the cheapo rockers on. The only way you would notice a performance increase would be if they were 1.6 ratio or better. But, if that were the case you'd need to make sure you have enough valve clearance.

[chev74]

but even if they were a good brand and ratio, and i could easily get new valve covers, no wonderful improvements would be noted, correct?

[Billla]

No performance benefit at all to roller (or roller-tip) rockers - the intent is to allow higher RPM/higher lift than what the stock stamped steel rockers can handle. This is another "race only" part that gets a lot of use in mild street engines.

Generally unless the engine is making > 1.2 HP/CID or seeing beyond 6,000 RPM regularly I recommend the Crane stamped-steel rockers with Parkerized and grooved rocker balls - cheap and reliable.

[special-K]

How many miles on the engine?Is it a good time for a cam?I`d only bother with the new rockers if I was replacing the cam & lifters.

[chev74]

only about 12-15000 on the rebuild. No new cam necessary.

[Slammed70]

Originally Posted by chev74

would simply replacing the mechanical rockers with roller rockers

Thats not just a simple drop. Need to pull the stock press-in studs, drill them out to 3/8, tap the hole and intall QUALITY screw in rocker studs. Guideplates to keep the pushrods from "walking", and you will need hardened pushrods to use with those shiney new guideplates.

Theres no real benifit on a street driven vehicle like everyone else said...faster revving is the only thing I would add.

[jamon8]

rocker arms are a wear item and need to be replaced as often as valve springs

put them on it will not hurt

if they are 1.5 they will not pull on the studs any more than the stockers

if you are running under the 400hp 6k rpm line then you can get away with pinning the studs instead of spending big bucks on guideplates and machining the guide bosses

[chev74]

thanks for the info guys!

[bdozeraz]

I would put them on. You will probably need different valve covers but you can get tall stamped steal ones pretty cheap. The will give you a little bit of performance gain. I beleave crane's add claims 10-15hp just by changing to the roller rockers. They greatly reduce the valve train friction. Have you ever rotated an engine over by hand with just the crank and pistons in? it turns over pretty easy. Then when you add all the cam lifters and set the rockers it is a whole lot harder to turn. The roller rockers will be more consistant ratio all the way across. You don't need screw in studs or guide plates they will align just lock the stock ones. You only need screw in studs or pinned press ins if you are running a really high lift cam and heavy valve springs.

[bryanw1968]

Originally Posted by bdozeraz

I would put them on. You will probably need different valve covers but you can get tall stamped steal ones pretty cheap. The will give you a little bit of performance gain. I beleave crane's add claims 10-15hp just by changing to the roller rockers. They greatly reduce the valve train friction. Have you ever rotated an engine over by hand with just the crank and pistons in? it turns over pretty easy. Then when you add all the cam lifters and set the rockers it is a whole lot harder to turn. The roller rockers will be more consistant ratio all the way across. You don't need screw in studs or guide plates they will align just lock the stock ones. You only need screw in studs or pinned press ins if you are running a really high lift cam and heavy valve springs.

I got the Comp Cams Pro Magnum stainless steel roller rockers and used the same low profile valve covers. You might want to check and see if they clear before you go blow money on valve covers. And, if you're going to take the time to drill out your rocker studs why not spend a tiny bit more and put 7/16" screw in studs. Heck, they might even be the same price as the 3/8" ones. Good luck.