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Author Topic:   Rolloer Rockers
WesternAuto17
Member
posted February 26, 2002 12:00 PM
There's a debate about roller rockers raging (well maybe not "raging", but that sounds cooler) in the street stock forum. What are the advantages of full rollers and roller tips versus stamped stockers? (Assume a flat tappet cam, SBC, 5500 to 6500 rpm)


Racer111
Member
posted February 26, 2002 07:52 PM
They will last a very long time but you can use or hide in there case, a roller cam.Thats where you can get more HP.


Monster
Member
posted February 26, 2002 08:19 PM
A. They are stronger- you'll never drive a pushrod thru the end of them, or burn a pivot. B. The ratio has a tighter tolerance(machining vs stamping). C. They replace sliding friction with rolling friction, which is always good. It requires less oil, it puts less heat into the oil, and allows that engine torque that was previously used to overcome that sliding friction to be put to better use, like turning the rear wheels. I vote for rollers!


sdhnc29
Member
posted February 27, 2002 12:54 AM
What monster said

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


Machinah
Member
posted February 27, 2002 04:56 AM
Roller rockers won't roll to full potential until 8000 rpm, and yes if you are using a roller cam, it does give you the edge at lower rpm.

The question, as stated fits my track rules more closely. We are allowed roller rockers but not roller cam/lifters. The rolloer rockers are no advantage at all on my 1/4mi track. If we could get more rpm I'd use 'em.

Flatlander
Member
posted February 27, 2002 07:40 AM
Where did you get your information that roller rocker's don't roll to there potential until 8,000rpm ?? The simple facts and gains about roller rockers are , less friction , stronger , true rocker ratio , increased valve guide life , reduced oil temp , ability to have truer rocker geometry , less oil needed for the top end , ability to run stud girdles that will keep truer valve lash and tie the entire valve train together , making the whole combo much stronger and much more stable . One of the main gains with roller rockers is strength . With today's cam's , and the tendency to run higher and higher rocker ratio's , and much higher spring pressure than in year's past strength is a big issue ! There have been numerous published dyno test's over the years that show a 10-15 hp gain in simply changing from stock stamped rocker's to rollers in most applications . Any time that roller rockers are legal in your rules , and you can afford them , then you should use them ! Why throw away all of the thing's that they will gain ??

Steve

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


Flatlander
Member
posted February 27, 2002 01:59 PM
You also asked about the roller tips they suck I woulnt recomend them to anybody I couldnt tell any horsepower difference and I kept shoving pushrods thru them and some just shattered Put the stockers back on no problems since. This is a pure stock no full roller rockers allowed or I would have them


Machinah
Member
posted February 28, 2002 05:26 AM
If you would look at what I wrote, you don't see me disputing the other advantages of roller rockers. I run Street Stock and the few 1000ths of a second in lap time that I might gain from running roller rockers is not worth the money. Rollers have come a long way in durability since I have gotten my information, but still have to be replaced more often. My biggest worry is setup and cost, not small HP gains. If I am ever in a class that gives me a good advantage running these, you bet I will have them.

Steve... what business are you in? What makes you more money? Getting a customer that is convinced that they need roller rockers or one that wants to keep the stock ones. If I were in your shoes I would want to make more money. Why don't you show us where the dyno HP gains occur? Why don't you show us the replacement ratio between roller and stamped? While you are at it show us the price of the average roller rocker that you supply. Please let us know what your source of information is, and don't use the manufacturer, they are also trying to convince everyone that they need these and leave out vital information that would disclude most applications.

My information comes from HP Books. These guys have researched these kinds of things as thoroughly as can be. The information comes from people who have actually been there and done that, and are not in the business of making money from information that has not been included. They actually have all of the equipment and know how to conduct a controlled, scientific study. Most of these sources are professional racers. I've also, over the years, read this information in a couple of Hot Rod magazines of which I can't remember the issue. Magazines are not always a good source though.

There are a lot of details to consider before deciding whether you -need- to spend for roller rockers. You can't just say that rollers benefit everyone and leave it at that. There are instances where roller rockers should be used, mine is not one of them. You have to have an open mind when it comes to things like this. I have been proven wrong more times than I can remember, but I know that I'm right on this. If you can show me good disputing facts that are complete and that doesn't leave out any details, I might change my mind. The problem is that you can write a small book on nothing but this subject alone.

Flatlander
Member
posted February 28, 2002 08:01 AM
I certianly don't dispute anything sdhnc29 says about this. But, maybe what Machinah is trying to get at is that roller rockers offer diminshing returns for his application?

We all know that there's a point where the extra cost outweighs the benefit. And who hasn't ever been down to his last 300 bucks trying to figure out what to spend it on?

I have no doubt that roller rockers offer a gain below 8000 rpm. I just wonder if that money (on my tight racing budget) can yeild a better gain elswhere...especially on an engine that wont see anything over 6500 rpm.

WesternAuto17
Member
posted February 28, 2002 08:56 AM
Horsepower isn't the only thing that matters when putting a motor together. I don't have a ton of money, so I want to spend the money in places where it can save other parts. The valve train is really important, skimp there and you can grenade the motor. An example is valve springs. Good valve springs don't make a ton of horsepower, but that's not wasted money.

I kinda think the conclusion to this topic is to use roller rockers if you can.

Flatlander
Member
posted February 28, 2002 11:02 AM

Machinah ,
First of all , I'm in the business of building race engines . In my business , unlike most other's , you sell a customer a part for his engine that will last , and not fail . The information that I supply on this forum is real life experience and knowledge from my own engine dyno (Super Flow) and chassis dyno (Dynojet) , not book knowledge . While I am in the business to build engines , and to sell part's , I am not in the business to sugar coat what I sell and to lie to my customer's . There is no book that can be written on the subject of "Roller Rocker's vs. Stock Rockers" , due to the fact that there is no comparison !! To compare these two rocker's would be stupid , and very one sided for Roller's . You say that you don't care about a couple of tenth's on the race track ??? I know racer's who would kill to be able to pick up a few tenth's !!!

As for the wear factor of roller rocker's , how can you think that stamped steel rocker's could possibly last longer in an actual race engine ??? Hmmm..... I wonder if all the Winston Cup teams know about this ?? Since they don't run roller cam's , and there restrictor engine's don't operate above 6,500-6,700 RPM , then perhaps stock rocker's is something they should look at using , with there multi million dollar engine budget's .

As for price difference , I sell Crower and Jessel rocker's , which in my opinion are the best made . If a guy is on a budget , then he can look to his Summit magazine and buy a set of Summit brand , or Crane rocker's for around $170.00 . In my opinion , $170.00 is cheap insurance that I will never have a pushrod stuck through my rocker with one lap to go while winning a feature . Win a race , you pay them off , lose one race because your rocker has a push rod stuck through it , and you will wish you had spent $170.00 !

I put roller rocker's on every race engine that I build , if they are legal for the class of car that the engine is being built for . I do not do this to arbitrarily sell a customer what he does not need ! I do this to ensure he gets an engine that will last , and to ensure that he is getting the most potential out of what he has just bought (the engine ). No where on this post have I tried to sell anyone a set of roller rocker's from talking about this subject !! What make's me more money you ask ? I'll tell you ...... producing a product that make's power , and will not fail !

I'm not sure what HP book's your reading , or who the author's are , but there "conclusion's " go against everything that every engine builder in this nation will tell you . Call Ron Shaver , Toney Clement's , or heck even every Cup team , and ask them to explain why they use roller rocker's . What HP book's are telling you this info ?? It can't be a Chevy Power book , because my friend Rick Voegelin writes these book's , and he knows better than to write something like that , especially since we have done most of his product testing for him over the years !

I stated the fact's in my previous post , based on what I and the rest of the world know and understand .

Steve

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


ryan
Member
posted February 28, 2002 02:12 PM
Just think if putting rollers in would gain you two tenths of a second a lap and you raced 10 laps that would be 2 seconds behind the guys with the rollers. That could be the difference between winning and losing


o5racer
Member
posted February 28, 2002 05:39 PM
at my track 10-15 HP can make a big difference. and 17.8 sec/lap vs 17.6 sec/lap is the difference between first and fifth. i may **** somebody off buy if someone honestly believes that a part that reduces friction and increases the efficiency in an engine makes no difference then they dont know very much about engines. on a 350HP 350 a 15HP gain is 4 percent. thats quite a bit.

heres something else to think about... all new cars are being built as absoluteley cheap as possible to save money. if you dont believe me just look on the interior of a new car. there is not a single ***** in sight, all snap to gether. if , say GM for example, was doing everything possible to save money when they build cars, then why do all the new v6 motors in the cars have roller rockers??


Monster
Member
posted February 28, 2002 06:04 PM
Steve said it all. What do roller rockers have to do with roller cams? They don't "roll to full potential until 8000?" That statement shows right there that you do not understand the concept, my friend. In year 2000,I was at a trade conference where HP books premier "engine builder" was touting some over the top, 30 year old theory on valve seat angles(which he recently published in Circle Track mag). There were actually hoots of derison from the normally polite audience, which consisted only of some of the top racing engine builders in the country. So go ahead and take the advice of HP's "racers" and ignore the real world. SOMEONE has to fill out the field in Hobby Stocks too.


Machinah
Member
posted March 01, 2002 05:18 AM
Well, it looks like some of you understand and have read what I wrote and some of you don't/havn't. I apologize for being so harsh to Steve, but I am still sticking to my guns.

We still have not seen the replacement ratio between rollers and stamped.

How many of us use the same rollers that are in a Nascar? How many of you have been watching the new tachometer feature at the top of the screen in the Nascar races? That tach goes over 7000rpm and approches 8000rpm constantly. Most of the time they hover between 7500 in the turns and 7800 in the straights. These have been long tracks with long sweeping turns. A track like Bristol would be very different. With proper oiling these rockers probably do roll just fine.

I'm talking about classes that are far removed from Nascar. I should have made myself a little more clear, my fault. Maybe I did sound as if I was trying to lump all together.

As far as a pushrod going through the stamped rocker, I don't think that anyone is getting my point. At my track, 1/4mi, fairly banked, my rpm is not going to go over 6000 without excessive tire spin. There are many running stamped and rollers. It seems that there are more rollers breaking their pins than stamped pushing the rod through. Stamped failure=1, roller failure=3... these are only the ones that I know about. This is not enough information to draw any conclusion, I might add. By the way, I am only looking at my street stock class and the bomber class, not sprints and modifieds where they can get rpms very high.

I can buy a set of new stamped rockers for $35-$40. I can buy a -cheap- set of rollers for $150, which I might add, will not function as good as a set that you actually spent some money on... then... I must buy a tall aftermarket valve cover, new studs, new girdles, and I'd better get an oil baffle to keep the oil on top of the rockers where it belongs because I had to eliminate the stock baffle. Guess what... I've just spent $350-$400 for the -cheap- solution when all I wanted was a set of roller rockers. Come on. I have not even begun to go into what must be done to make these cheap rollers oil properly, if it can be done at all.

I didn't say that rollers are completely unecessary for -all- types of racing. There are some cases where they are unecessary, and numerous cases where they are not.

Steve, you know far more about a racing engine than I do, that is a given fact. No matter who verbal information comes from, I always try to find -real- research to back it up or dispute it. It is the only way to be sure and nothing is 100% acurate.

As far as the rpm being 8000, I must admit that my information is 6 years old. This limit may have edged down somewhat by now. The way it is stated is that any rollers at any lower rpm than 8000 will only roll a little and stick a little. The closer that you get to 8000 the better they roll, and at 8000 they are truely at full roll. I'm sure that these figure must vary by a couple hundred rpm or so. It does not distinguish between cheap rollers, mid-grade and top of the line. The only distiguishing remarks made are that any cheap roller has not got good enough oiling to make them a true roller at any rpm, and that modifications will be needed to make them roll better.

Again, Steve, I do apologize for being overly harsh. You probably are not trying to oversell your customers, and I'm fairly sure that you are giving them the best product that you can. I still have to disagree on this subject until someone can give me real scientifically studied information which will dispute this. Thanks.

WesternAuto17
Member
posted March 01, 2002 08:50 AM
Thanks for all the input, I'm going to use rollers. I will be using new 215 Dart Iron Eagle heads. What will I need to besides buy rollers and stick 'em on?


sdhnc29
Member
posted March 01, 2002 09:05 AM
I actually find this subject to be quite comical , yet very sad at the same time . It amazes me that there if enough misinformation to actually convince someone of the conclusion's that you have come to about roller rockers . You claim that everyone must supply scientific proof that roller rocker roll . Yet we have heard no scientific proof from you , other than a HP book comment , to prove that they don't . Where is the science in an article or two by someone ignorant enough to write about stock rocker's being better than roller's ??? I think the scientific proof that you require , will be found in the engine builder's who actually use these product's . Not in a book written by someone as ignorant as the author of the book you mentioned . As I stated before , I have dyno tested , and I know the result's ! Does your book mention roller cam bearing's ?? Can it tell you the horse power gain's produced by these , vs. conventional cam bearing's ?? I doubt it ! Well ..... I can , because I've tested this ! Like I said in my earlier post , call other engine builder's and ask them this question about roller rocker's !

If it comes down to a guy who must put food on the table for his family , or buy a set of roller's for his hobby stock , then it's a "no brainer" , stick with your stock rocker's . At that point , the best part for your engine really doesn't matter , or it shouldn't . But for people who can afford them , there is only gain's available .

I'll consider this the end to our discussion , because it is pointless to continue . I have done test's , I have done this myself , and I know the result's . Your conclusion's are based on book's , written by people (like monster described ) "with antiquated idea's". There is no science here , just fact's and real life experience . If you don't believe me , and every other engine builder in the world , then it's all cool . But in a true scientific atmosphere , you must draw conclusion's from what is fact , and not fiction . I've listed that fact's as I know them to be true and accurate . From this point , everyone who reads this post can draw there own conclusion as to what is fact , and what is fiction .

Good luck with your racing .

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


Scoot
Member
posted March 01, 2002 10:20 PM
Can someone tell me what you would set roller tipped rockers at. We bought a motor with a roller cam, lifters and roller tipped rockers. But we're not sure what to set them at.

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Scoot
Smith Racing Team
870-365-5989


sdhnc29
Member
posted March 01, 2002 10:31 PM
Scoot ,

Are you talking about valve lash , or where the roller tip should be positioned on the valve ? If it's valve lash , then you should contact the cam manufacturer , give them the part number / grind number of the cam you have , and they will tell you what lash you need to run . There are too many different cam grind's , with too many different valve lash setting's to guess at it . If your talking about roller tip placement , then refer to the post on push rod length , and it is explained there .

Steve

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


drt mod rcr
Member
posted March 01, 2002 10:46 PM
We run on a limited budget and last year was our first year in anything. We ran a 358 cheap motor. However we did run summit roller rockers and a stud girdle from speedway motors. Never had a valve train problem once. Top end looked new after the season was over.


Machinah
Member
posted March 02, 2002 03:25 AM
This will be my last post on this subject.

Steve, I take back my apology. You didn't even read what I've written.

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