327 Chevy, roller rockers or stock?

Alright, guys. My '54 Chevy 2 door is down with a blown head gasket. While I'm changing that, should I switch to roller rockers or leave them as they are? It's a '68 327 crate motor we put in about 9 years ago that's currently just running a quadrajet, but that too could change in the tear down I've driven it out of state and back once, otherwise, she mainly just does weekend car show duty, but I would like to put more miles on her, further distance shows and all that.

So what would you guys do? All opinions and comments are appreciated! I'm still at the parts gathering stage and just wanna know what y'all think. Thanks!


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Stock rockers are just fine, less parts to fail. Gary

 

Stock are traditional.

 

Roller rockers aren't going help you very much on a basically stock 327.

With a lumpy cam, heavy spring pressures, high Revs and such they can help quite a bit. Without all of that they don't do much. Roller rockers are more of a "supporting modification"

 

If you do go with rollers, get the good ones. I put a set of cheapies from Speedway ($100/set) on a boat once, and one of them broke almost immediately. That being said, it's not worth the expense on a relatively stock engine.

 

Roller tip rockers are a good compromise on a basically stock engine. I have had a set on the 327 in the Studebaker for several years, and just put a set on my 427. both are solid lifter factory cams in my case.

 

You wont notice any difference in anything but your wallet. Stick with the stock rockers and save your money.

 

Hmm... everyone here seems to be saying not worth the price. Most Racers say they are cheap and easy HP. I understand they would help most with big valve springs ect. Chevy uses them in todays V-8's. They don't spend money they don't need to.

 

If you are building up the engine for higher RPM and lots more power, by all means go roller. But if you are just going for a few upgrades, roller rockers should be way down on the priority list, Aluminum intake, headers, better ignition are places to start. The next level would include cam, springs, port work and roller rockers.

 

We probably should've asked what rpm range you generally run in but the assumption is that it isn't that high.
New Chevys use a rocker with a roller trunion, not a full roller (tip).
If you're mostly cruising around, it's not likely that you'll notice much difference.

 

You run roller rockers if you need to, not just because the idea sounds neat. I get the feeling that you are more of a need to guy and not a want to guy because you asked instead of just screwing them on and say, "hey, I got roller rockers!!!!!"

Sounds like you are running a putt it around car most of the time and not really beating the hell out of it when you do go for a long ride. if the stamped steel rockers were working for you before, you don't make any major internal changes then they will still work for you.

 

A good compromise are roller tip rockers. Comp Cams used to make them.

 

I read that roller rockers reduce frictional horsepower loss, to the tune of about 10-15 horsepower in some applications. On my 427, with no other changes, my idle speed went up from 800 to 1100 rpm with just the installation of full roller rockers, so there is definitely less parasitic drag. This is why the OE's went to roller cams in the first place. The roller tips alleviate some of the stress on the valve stems, and arguabley cause less wear on the valve guides although with just roller tips there is still the parasitic drag. Probably not too noticeable on a stocker, however every little bit of horsepower and efficiency count. Why are guys running them in the first place. We have all spent plenty of money to free up every bit of horsepower we can, even in the smallest increments. Why do we put them on a race motor, but not a street motor? If its all about saving a buck, We are in the wrong hobby, that's for sure.

 

Eric,
Yes they do reduce parasitic drag although I doubt that you will notice 10-15 HP on a stock 327. Then there is the cost/gain on a fair grounds putter and there is a reason why I am mentioning this so bear with me.

A lot of the off shore roller rockers weigh more on the valve contact end then the more expensive roller trunnion rockers like say Harland Sharps or even stock stamped rockers. That actually puts more strain on your valve train and can actually hurt you, more then help you. A set of quality roller rockers can run in the 400-1000 dollar range these days. Not a viable addition to a stock run about motor.

Your logic is good but by the same logic wouldn't we all be running a good set of shaft rockers on everything that we own, shaft mounted rockers are proven to be way better for valve train control than pedestal mounts.

I run rollers on my street engines, but I just don't own a stock engine (normally). I have a set of cranes that were not offshore parts yet on my 355. they have been on there for about 150K and are due for new trunnions now. yes they made one helluva difference in the performance of that particular engine, but it makes more then 1 HP per inch and has canted valve heads. The biggest performance gain was not changing stock stamped rockers on the side of the road. The canted valve heads made them necessary.

Like I said before and I will repeat myself, they are something that you run out of need.

There are two schools of thought in hot rodding, one is if it aint broke don't fix it and the other is if it aint broke fix it 'til it is. My thoughts on this particular question with thre information given by the OP falls into the first category.

 

You won't gain much from the roller tip, you will se an increase from a rocker ratio change. Stock is rated at 1.5 ratio many don't achieve that. A 1.6 ratio rocker will provide more lift making your cam act a little larger. Check circle track catalogs, I've seen stamped 1.6 ratio rockers for claimer engines at very good prices, can't remember where

 

I agree with the above, AND I swear the engine will run cooler due to less friction and I KNOW it will rev quicker---I'm on my 4th engine with roller rockers.

 

The factories do it for no other reason than to raise their fuel economy to meet the government's CAFE ratings.

 

go with rollers 15 hp ---y- not
you'll sleep better at night because YOU feal better

 

If you have a cam with over .500 lift they keep a lot of side thrust off the valve stems.

 

If you can score good ones at a good price, run them. If not, just stick with the stockers. You mentioned you want to put miles on your engine and it's a stock crate engine. The stock rockers are time-proven and reliable. One less thing to worry about on a long-distance trip.

 

I think a lot of this decision has to do with the condition of the current stock rockers. If they are not worn to the extent to require replacement, I would continue using them. But closely examine them after a good cleaning, as a worn valve stem pad can easily get worse in a hurry and lead to a dropped valve and all the grief that means.
If a substancial number of rockers are worn and needing replacement, then go for the rollers.And as an aircraft machinist for a major airline before I retired, I've seen my share of bearing bores in aluminum parts that had "egged out" due to the ductility of the aluminum.
That's why I went for the Comp Cams chrome moly steel roller rockers.

 

I don't remember where I read it, but the author claimed that for a roller tipped rocker to be effective the roller would need to be something like more than 2" in diameter.

 

I have Crain 1.5 on my 350 only because I took them off my racing engine,when I quit. They've been on my street car for atleast 12 years with no problems.

 

if you want to increase your valve action with them without going to new cam- you can get some that have a 1.6 instead of 1.5 ratio- that's a bit of a bump right there to your valve action. You'll save a little on friction, but like others said, the weight on the nose cancels out the overall reduced weight of aluminum rockers- if you have the cash and want them, i think Comp sells steel ones that aren't as light as alloy rockers, but the weight is concentrated at the fulcrum and the nose is lighter- that's what i'd buy if i were set on doing an upgrade- i definitely would NOT do aluminum rollers on your particular build/usage. I've got a hot mill with aluminum rollers in my mopar and most all honest companies will tell you that it's not IF an alloy will fail, it's WHEN it will fail due to fatigue of the aluminum. They dont build bridges out of alluminum. -rick

 

For a street machine don't go with aluminum go this route:http://www.ebay.com/itm/SBC-Small-B...Parts_Accessories&hash=item486720f63c&vxp=mtr

 

I used Harland Sharp in my 383, I was very happy with them. I recommend them if you have the extra cash.

 

Everyone who encourages the OP to go to 1.6 has failed to also tell the OP that he'll most likely have to change pushrod length too! You can't just slap a set of 1.6 rockers on a SBC without checking the wear pattern on the valve stem, or it can end in a catastrophic failure. If the longer ratio rocker doesn't roll on the center of the valve stem it will ruin both the rocker and the end of the valve stem.
Considering the OP is talking about a stock engine, and no other changes, it's still money wasted. I doubt a dyno test before and after would even see 5 hp gain. If it was a case of roller cam vs. flat tappet, I'd be all in favor of it, and also doing the roller rockers at the same time. But it's a completely stock engine.

 

Heck if you gonna tear down the engine that much to install roller rockers ya might as well put that nice cam in while your at it.
-Pat

 

I have an acquaintance that races a BBC with Harland Sharp's that he bought in the later '60s or early '70s. They were pricey when he bought them as they are today.

There is an upside to the price, they really stand behind their product. He had one fail in '98, I was there when he pulled the rocker cover. He called Harland Sharp and asked about buying a new trunnion and roller tip. They suggested that if one failed they probably would all fail and he asked about new trunnions for the entire set. They said, "send them to us which he did." The entire set came back rebuilt, no charge.

 

A cam replacement is a big step beyond roller rockers.