Per a vendor thread: http://www.motoringalliance.com/forums/sponsor-messages/3508-true-performance-valve-spring-kit.html What are "conical" springs. Why do we want them and how are they different from stock, or other aftermarket springs? This is an honest question on my part as I would like to learn. Please explain in simple English. Don't tell me to read a book, or look it up. And folks, let's keep it civil.
Geez....you want it in simple English, you don't want to read a book or look it up AND you want it kept civil??? Dude, I have no clue. We'll both have to wait until someone smarter than us wanders thru.
Hey, I am to the point where I have my wife open my beer for me, lest I cut my self. They are not all twist offs you know.
Those twist offs can be nasty at times. I'd find it interesting also, but if no one in the know chimes in with any real knowledge, can we change from conical to comical springs, just think of the possibles we could make a thread like that go:lol: Mark
Well.....I could try and explain what Lynn explained to me but....:crazy: :lol: What I can tell you is that on my particular car it made a major difference, according to my butt, in response at 6k rpm and above I have the Cosworth BVH and they used the normal double spring. Now the, "conical" spring I believe is also called a, "beehive" spring. here are a couple of quick quotes: From the March, 2009 issue of Corvette Fever Performance tricks are usually just sleight-of-hand changes that dolittle to improve performance. After all, if it was that easy, everyonewould be doing it, right? But the simple fact is, valvespring technologyhas been moving on--in giant leaps these days. Ask any NASCAR enginebuilder behind closed doors, and he'll tell you about his lightweightretainers and valvesprings, perhaps the most significant change in thelast 10 years. These beehive-shaped springs feature a lighter retainerand a lighter-weight spring. And: The beehive spring shape has become the buzz lately, and it's commonlyused in many OE engines as well as Nextel Cup competition. Why? Thebeehive shape is more stable than standard cylindrical springs, And: "Beehive springs feature smaller, lighter retainers, greatly helping theengine achieve much higher peak rpm," said Chris Douglas of Comp Cams. One last quote from, "Stock Car Racing": However, if we are talking about the pinnacle of spring efficiency, short of air springs, then the Comp Cams beehive springs almost certainly take the top spot. Our tests over the last three years have shown that on average, these springs will deliver about 1,000 rpm more for the same poundage, or the same rpm for about 5 percent less seat poundage and about 20 percent less over the nose. There is more to it than just rpm. Because these springs are so much better behaved (in terms of resonance as the engine goes up the rpm range), output is often improved. This happens primarily at the points where the original spring has gone through resonance and some minor valve bounce has occurred. So, no I did not do a "before & after" dyno, but the difference is there :cornut:
Some of my observations and thoughts; those springs closely resemble customs made Peterson PAC Racing Springs - The world's premier valve spring manufacturer., which is a good thing because Peterson makes excellent valve springs. Below is a photo of the spring goaljnky asked about on the left and stock on the right. Note the spacing between coils on the left spring due to one less coil than stock, that feature will allow greater compression before one coil contacts another. If there was a cam lobe that could push the stock spring far enough to make contact between the coils, the aftermarket spring would have an advantage. Other positives include smaller OD winding at the top of the spring so a smaller/lighter retainer can be used, and less weight for the spring. I had one of those springs tested along side a stock spring, and another popular spring made by SuperTech.SUPERTECH V 2.0 :::::::::::: Indeed the "conical" spring had greater seat pressures than stock but not excessively, they were also the correct height. The pressure increases at various stages of lift were appropriately linear as well. Overall a very good spring that could tolerate high rpm operation and high lift cam profiles, based on the bench test. The SuperTech spring had greater pressures than the conical spring, which could discourage valve bounce on the seat, if a cam with radical ramp profiles was used, and it could raise the rpm threshold where valve float might occur. Jerry asks "why do we want them", you would want them if you perceived a need for them. Unfortunately, the MINI need factor has not been empirically established. No one has yet to put a MINI motor on an engine dyno and test to the point of valve train failure, and that includes valve bounce. Even if in-the-field valve or seat failure reports are attributed to bounce or power loss due to float; how can we be certain it was not an issue with the valve seat to begin with or non-concentric ground valve, etc? Also, there is no camshaft designed for the MINI that would create enough lift to bind the stock spring. If you want to cover all bases than by all means go for it, the mentioned conical spring can certainly handle a wider range of operational possibilities than the stock spring.
Performance Spring kit.... YES!! Why to you want them?? Actually the Super tech springs I tested against the STOCK were LESS than stock... go figure. by 20% ( Plus or minus a few pounds..) installed at correct height. and 11% less than stock at .400 lift. When with a racing camshaft profile, and opening the rpm up to 7800-8000+ rpm.. the seat pressure and compressed pressures need to be increased. ADDING a lot more boost.. Ie: smaller pulleys/ turbo.. ect.. this also requires more pressures on the seat. "Seat bounce " is talked about in most Camshaft articles and performance articles on racing and cylinder Head building and needs. ( sorry.. if you feel the need to research.. you WILL have to read!! LOL) The Conical design , as stated in the examples by Jiminni says pretty much it all.. the new design of the conical ( beehive type) is the future.. it will free up spring weight.. retainer weight.. and spring harmonics at high rpm. SOOoo.. it is a proven NEW design. The Dual spring with the spacer ( super tech type) is a good spring.. designed for a Nissan, and then adapted to the MINI head. And the pressures are a bit weak.. yet they seem to be fine on the most applications for the average driver!! The single conical spring by NITROSTICK is designed for the performance MIN Head. installed is +20% more seat pressure and about 5% more at .400 lift!! IF you dont need the extra safety for high revs.. or radical cams ..or both, then you dont need these. Cool? The COST difference between the Dual spring and the Nitrostick is like $5.00 more for the NS set up. HOWEVER IF you are at the 7800-8000+ revs, and on the track more than the street.. these could be just the bit of marginal safety you need!! AS stated in thread ... http://www.motoringalliance.com/forums/sponsor-messages/3508-true-performance-valve-spring-kit.html .. Thumper
Thanks Mike. I had to cut and paste my info, but it sounds better coming from a real person :lol: Hopefully the designer may be able to add a few thoughts
Just chiming in... The usual suspect (Lynn, despite all the crap he catches on the boards, he's been building and using race engines for a long, long time. He knows his stuff and gets in touch with experts when he doesn't...) came up with these based on what was out there for the MINI, and the lack of really good alternatives. It seems as though most (all?) of the previously used spring kits have some compramises in them. Keith is correct, these are made by Peterson, and have all the fancy tricks that Peterson uses in making springs. As stated by others, the bee-hive geometry has two main advantages: Reduced ressonance and retainer mass. Both of these things mean that they will be better behaved at higher RPM. One thing not mentioned by others is that reduced mass leads to reduced inertia, meaning that the same spring force will hold everything where it needs to be to higher RPMs. Another feature of is the spring wire, that is oval, not round. This results in better stress distribution throughout the spring, and a higher possible lift before bind occurs (click here for some cool graphics and the like). While the only cams that go that high for the MINI are currently vaporware (there are some cam sites that LIST race cams like this, but I don't know if any have ever been ground.... And if you did get one, it would bang the snot out of the spark plug tube.) One other thing not yet mentioned is that the Ti retainers are modified from other pieces for the MINI app. That means two things: you can't get them anywhere but those that sell the NS spring kit; and that they are lighter still than stock or aftermarket replacement parts. Yes, they have a Crower part number on them, but it's a captive part and won't be sold if you just call up and ask for them. Anyway, anyone who sells the NS cams can get these springs for you, though Thumper is the first to push them. If you look hard, they are on the FES web site here. If you are a vendor and want to carry them, send me an e-mail at [email protected] [ame="http://www.youtube.com/watch?v=019Jyn9oB5k"]Cool Vid of Spring Testing [/ame]. Matt
Ok, so you tested the wrong spring. The stock spring has been in MINIs shifting at 9k rpm, various other aftermarket valve springs have been in use with turbo conversions, reduction pulleys, drag and road race; where are the MINI application failures? It's another option and a good one.
It might be helpful to add a little to what Thumper and Dr. Obnxs have said. The reason dampers or shock absorbers were installed on cars was the cyclic frequency of the spring. The conical spring has several frequencies, which cancel each other out. Older technology valve springs use double, and sometimes triple springs to do the same thing. The springs with the flat wire inner spring actually acted like shock absorbers because they rub against the outer spring. The new spring weighs less for the same control, so you can run less spring pressure for a given cam and engine speed. This will make valve seats last longer. Or you could rev the engine higher.
Good info, everyone. I am drinking and posting, so please excuse any stupid questions. Dr. O: in the video you posted. Is the spring on the left different then the one on the right? Are the springs supposed to spin? Thumper: what do you mean the ones you tested were less then stock?
drinking and posting is much better than just posting.... The beehives are the single spring at the beginning of the vid. Then there is a dual cylindrical set up. The point of the vid is that the beehive has less higher mode oscillation. As the RPM gets higher and higher, those ressonances can have spring mass flapping up and down at a pretty high velocity. This causes variations in spring seat pressure as well as how hard the spring is pushing up on the valve. Float or bounce can result from this. The rotation is there on all springs like this. As the spring compresses, you get a torsion as well as a compression. The rotation is what happens because of this. When I first came across the vid, I watched it for quite a while... I guess it's a physics thing... Anyway, these non-ideal spring motions are really good examples of what is known as mode-coupling, and shows how what one would think of as a pretty simple system is very complicated in real world applications. As far as when one gets real world benefit from improved springs, I'm not too sure. Jimini says he felt the difference, and he's not going to the RPM that Thumper is quoting. It's not just RPM that matters, it's also cam profile. If you have a good engine builder and don't want to learn all the ins and outs of this stuff, talk to them and trust their judgement. As far as other springs spinning to high RPM without failure, sure that's true. But to say that since they didn't break they are good for the application and particular use case is a logical leap that one can't take. They may or may not be good in the app. That's really a different question. That said, I'm sure that with carefull spec selection and the like, one can find other manufacturers that make springs that are well suited for the MINI at higher RPM. That's how these were found and selected! But it's also true that some of the springs selected for the MINI just plain suck and are a step worse than just running stockers. Anyway, hope we can keep this civil and helpful so it doesn't become yet another thread that should leave skid marks as it swirls down the bowl. Matt
You can do some work yourselves... one case in point. A person was PMing me about how he was building his engine up... BVH, valve selection, cam etc. getting parts together so a local head builder could do the work of actual grinding etc. for him. He found a set of "MINI" springs on eBay for $50!!!!! When he sent me the specs, there was a reason that they were cheap, they were weaker than stock. Could they be made to work with spacers? Maybe.... But he hadn't bought any. He didn't even know how to read the specs... He'd already bought the springs, and I hope his head builder catches the problems during the build. You can lead a horse to water.... If you search around on valve springs for the MINI, you can find a large amount out there! I was surprised. Most adds don't even list spring spec's. What are you buying? How does one even know? Point is, many who buy them don't even know about how to have the conversation about why is this spring package good for me or not... Back to springs. For those that are running cams with modified red-lines, don't forget springs as part of your valve-train build! Like all parts for our cars, choices were limited early on, and now there are more. The NS valve spring kit was chosen to take advantange of proven technology from leading suppiers that is well matched to many high end use cases for the Tritec. should everyone go out and buy them right now? While I'd like that, the answer is no, they aren't needed by everyone. Are there other options out there that can do the job? Probably. Never said there wasn't. Are there people out there who can benefit from well matched valve spring sets that aren't currently running them? I'm pretty sure that's a yes. This product is aimed at them. There's also the claim from one of the mags quoted that you can get better valve control out of the beehive/Ti retainer, and this should lead to less valve seat abuse, but to tell the truth, I don't know if this is a real world problem on the Tritec. Maybe those that actually build heads can say if they've seen damage like seat cracking or recession into the head. I honestly don't know. Matt
Well to be honest, it seems like on the Cosworth head for some reason they used smaller springs that required spacers, I was told they were SuperTech springs. When a designer here called Cosworth they had responded that they had so much money invested in the head that they used springs that they already had, not Tritec specific springs, as are the NS springs. But they assured that the springs were "adequate for the job", but as said by Matt and Mike, not the best match for our engine. Hope that helps? I would bet that only the, NitroStick Series Valve Spring & Retainer Kit, is specifically made for the Tritec motor :cornut: