Daeron Posted October 30, 2008 Share Posted October 30, 2008 3) Lack of Zinc in modern motor oils is a hot topic recently, especially for flat tappet cams. The domestic V-8’s with flat tappets are more susceptible to cam failure due to this vs the L-series with the V8’s need to “rotate†their lifters. Interesting side note: I saw a lady getting a quart of motor oil at wal-mart tonight. Accel brand Motor oil for "engines in model year 1988 and older vehicles," SAE grade SF. ZDDP, anyone? A quick googling reveals that I am NOT the first to make this discovery (chevelle and corvette forums, as well as antique studebaker were noted by this reporter) and that opinions on using a product of such apparent quality (sarcasm, looks cheap) in one's engine abound. However, I wanted to mention it to somebody.... Quote Link to comment Share on other sites More sharing options...
1 fast z Posted October 30, 2008 Share Posted October 30, 2008 I would certainly agree that the base circle of the roller would change the events dramatically at the valve, granted. However, I am very surprised to hear the consensus here is that the roller cams need to be of a HIGHER Rockwell value. I can't seem to understand the why. Why would a lobe that has a WHEEL ROLLING over it need to be harder then the stock cam that has a rocker that SLIDES metal to metal? Isn't the REDUCTION of friction(thereby wear) the whole point of a roller? Yes, Higher lift cams are a byproduct of this. And, 50-75 HP on these engines is STILL 50-75 HP... Even a 400HP Turbo motor could use that, couldn't they? I SALUTE you for your AWESOME observation, and creative thought process, MYSELF. The very best luck to you, if ya give it a shot!! Get a kit reasonable and reliable, and lemme know! I want you to design a BALL BEARING with the races soft, and the balls hard, and you tell me how long your new designed bearing last You would NOT get 50-75 HP if you converted a solid setup to a roller, plain and simple. I would be supprised if you saw 10 RWHP on a dyno. There are much better mods for the time and money spent. Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 30, 2008 Share Posted October 30, 2008 I don't think there is a complete head out there that anyone wants to share info on, otherwise that info probably would have surfaced already. That is a grossly inaccurate assumption to make. Perhaps the people who paid good money for the rights to the existing research are sitting on it? Perhaps because nobody wants to actually pay for the information themselves, or to in anyway amortize any investment in R&D, sourcing, etc... Maybe one guy bought the head, and the other guy bought the rocker arms and all the relevant information. Surmise all you want, but because you haven't seen something doesn't mean it doesn't exist. That is downright foolhardy, especially in light of the above commentary from JeffP and myself surrounding the subject. Sharing information is great when you are the recipient of free information. Giving it up when it represents a potential competitive disadvantage is equally foolhardy. "Sharing" information will come in due time, after some events take place. But pressing the issue isn't going to make it happen any quicker. Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 30, 2008 Share Posted October 30, 2008 I’m curious, if you don’t mind sharing, 1) how much, and of, 2) what gain are you expecting these roller rockers will afford vs the current design? Are you trying reduce valve train friction for better fuel efficiency? Take advantage of more aggressive ramp rates allowing more lift under the curve for a given lobe profile, (more power with less compromise in drivability?) Jon already brought up the question, is it really worth the time, money, and effort for how much gain in what area, not taking into account the amount of research and development required that will allow you to take advantage of what roller rockers offer? I’m assuming the perosn Tony mentioned that has done this, has been able to meet or exceeded OE valve train geometry, stability, and durability with these roller rockers?... Well, that was a long,detailed response that the Frankfurt Wireless Internet System ate. I shant type it again. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted October 30, 2008 Administrators Share Posted October 30, 2008 Well, that was a long,detailed response that the Frankfurt Wireless Internet System ate. I shant type it again. Those comments were in regard to Toddskis wanting to build these on his own, which I then apologized for. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted October 30, 2008 Administrators Share Posted October 30, 2008 .... And, 50-75 HP on these engines is STILL 50-75 HP... Even a 400HP Turbo motor could use that, couldn't they? ... Wait a tic… You guys are starting to misconstrue what was said regarding the 75 HP. He didn’t say that roller rockers would “free-up†50-75 HP, he said that is how much power it takes merely to operate the stock valve train at 5000 RPM! If the roller rocker cam was ground so that it mimics the OE valve lift curve, It might free up 10% of the power used to operate the valve train due to less friction. Lets give it 20% for the benefit of the doubt. That calculates to 15 HP reclaimed to the flywheel. I recall hearing about a dedicated dyno test, Small block V-8. Flat tappet vs Roller cam how much power does the flat tappet absorb vs the roller tappets, everything else being identical. Roller tappets freed up on the order of 10-15 HP. A SBC has 16 valves vs the Datsun 12, at that, my 20% figure above looks a bit optimistic. Quote Link to comment Share on other sites More sharing options...
PalmettoZ Posted October 30, 2008 Author Share Posted October 30, 2008 That is a grossly inaccurate assumption to make. Perhaps the people who paid good money for the rights to the existing research are sitting on it? Perhaps because nobody wants to actually pay for the information themselves, or to in anyway amortize any investment in R&D, sourcing, etc... Maybe one guy bought the head, and the other guy bought the rocker arms and all the relevant information. Surmise all you want, but because you haven't seen something doesn't mean it doesn't exist. That is downright foolhardy, especially in light of the above commentary from JeffP and myself surrounding the subject. Sharing information is great when you are the recipient of free information. Giving it up when it represents a potential competitive disadvantage is equally foolhardy. "Sharing" information will come in due time, after some events take place. But pressing the issue isn't going to make it happen any quicker. Hey Tony D- I didn't say that the head did not exist, I stated "I don't think there is a complete head out there that anyone wants to share info on, otherwise that info probably would have surfaced already". If someone has put alot of time and work into fabricating one up, with the idea of one day trying to produce and sell it, I can understand not wanting to disclose what they have done. Quote Link to comment Share on other sites More sharing options...
Guest Widebodys30 Posted October 31, 2008 Share Posted October 31, 2008 Wait a tic…You guys are starting to misconstrue what was said regarding the 75 HP. He didn’t say that roller rockers would “free-up” 50-75 HP, he said that is how much power it takes merely to operate the stock valve train at 5000 RPM! If the roller rocker cam was ground so that it mimics the OE valve lift curve, It might free up 10% of the power used to operate the valve train due to less friction. Lets give it 20% for the benefit of the doubt. That calculates to 15 HP reclaimed to the flywheel. I recall hearing about a dedicated dyno test, Small block V-8. Flat tappet vs Roller cam how much power does the flat tappet absorb vs the roller tappets, everything else being identical. Roller tappets freed up on the order of 10-15 HP. A SBC has 16 valves vs the Datsun 12, at that, my 20% figure above looks a bit optimistic. Copy that. Been so long since I cared about V8's, I'd forgotten what the percentages were. I though it greater, Myself. Faulty memory? Less than 20 Hp would be an expensive experiment... Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 31, 2008 Share Posted October 31, 2008 What do you guys think the returned frictional decrease would be at double that speed? The eaten "Frankfurt Reply" was a discussion of "area under curve at a set lift figure" and boiled down to the supposition that if you have a head that is already ported to it's potential for flow, then the only way to make it flow 'more' is to somehow increase the area under the curve of the valve being open and flowing. So it gets into the ramping issues Braap Discussed, as well as some modifications beyond the original design parameters wherein the cam towers are reworked to allow a split design, removing a lift constraint imposed by cam bearing diameters... And in the summary I basically agreed with Mortensen that the application would not be a street friendly setup. It could be but it's not the focus of the development at this point in time. There are places where something turning 9000+ rpms would welcome frictional reduction and the ability to have an agressive ramp on the cam, yet retain valve control with lighter springs. I'll give you a hint: Driving in Michigan during December got nothing on the salt spray you encounter where it's envisioned to be used. Well, I've gotten about 4 hours sleep in the last 62, and I'm about to go melt into my bed after taking a shower. And then get up to go to work in about another 10 hours. Sleep is not cumulative... Quote Link to comment Share on other sites More sharing options...
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