I need help picking value springs for my cam project. After hours of scanning the forums, visiting every cam manufacture's web site and analyzing dyno sheets for powers curves I've decided on the Texas Speed 224R cam on 112. I know, why so much deliberation for such a mild street cam... Everyone raves about it for what I'm trying to do. Anyway, my goal is nice street manors, a big fat/flat torque curve and peak HP not much past 6,000 rpm. The car is used for cruising. Durability and longevity are important. It won't be going to the drag strip or seeing the rev limiter (too often).

My though it that the lower spring pressure of the beehives will be easier on the entire valve train and help the long term. This isn't a race application so the safety net of the duals seems less important. But, max lift for beehives is .600 lift, which is exactly what the 224R is. So, am I testing the limits of beehives with this cam? There are some beehives good to .625" - should I go that route? The price difference is $100+/- - that's not the issue, just trying to put the correct setup together.

The rest of the set up is 01, 6M, catted longtubes w/Tis, cold air. The stock 241s will be ported/polished when the cam goes in. Oil pump and timing chain too.

Thanks for the input.

 

I had beehives on my C4 until one brook, then I switched to duals.
I am not sure what is on my C5.

 

Mild setup. Beehive.

 

I believe the nitrated PAC 1518s are good to .650. That said, I'd still vote for the duals. So far I've got somewhere north of $30K worth of reasoning behind that.

 

I went PAC 1518's on my setup (610/.614). It's been good so far..(1.5yrs, ~3k)
PAC or PSI make beehives that are good past .600 lift.

Yeah, you have some more insurance with dual's but you also are adding in extra valve-train weight. Maybe for a low redline build it not such an issue...

http://www.hotrod.com/how-to/engine/...-valvesprings/

 

I'm also running pac 1518's but I'm not sure if they are available anymore, I have read a few threads where guys were having a hard time finding them nowadays... personally I would run a high quality beehive on your setup... you want good seat pressure and just enough open pressure to control the valve without float... too much pressure and you are just prematurely wearing and putting added stress on valvetrain parts and your timing chain... another benefit of beehives is less overall mass

 

PSI They're the manufacturer, not a reseller. LS1511ML FTW......... Part of their Endurance Series. Good to .625

http://psisprings.com/index.php?opti...les&Itemid=155

HTH

 

I run the PSI Behives and like them. No issues. I did notice that the price actually went DOWN on them recently! But I don't think id run a cam with anything over 600 lift with these springs. Id go duals for that. I do wonder if any one has actually tried running more then 600 lift and not had any issues?

 

Cant always get caught up in the baby cam specs. 224R has decent lift and is on XE-R lobes I believe...which are on the aggressive side. I'd run a dual.

 

I would recommend dual springs. We put a similar cam in ours many, many years ago (got the heads & cam kit from A&A). The cam was a comp cam 224/224 / and .581/.581 on 114LSA. Pretty mild cam by today's standards, but it served us well for many miles, even without a tune. Of course, it woke up some once we got it tuned.... The kit was installed in Fall of 2001 at about 14k miles. We now have 114k miles on it. Driveability has always been great and we consistently get 30 to 32 mpg with it.

The only issue we had was about 10 years ago. One of the springs broke (the kit came with REV dual springs). The inner, second spring, saved the internals. The car still ran, just didn't like to start or idle well. We replaced all the springs with Patriot Gold duals. They are still running just fine today. Personally, I like the added safety of a dual spring for that just in case situation....

 

Good feedback, thanks. Maybe I'm over estimating the stress duals add to the valuetrain/timing chain considering you have 100,000 miles on the set up and got 70,000+/- out of the first set of springs.

 

I cant argue with the added reliability of two springs. But that reliability is also kinda negated by the fact that they recommend changing the spring like every 30k miles or something to make sure they don't break.

Its my Understanding from researching and reading that there isn't one person who has had a failure with PSI beehive springs which is why I went with them. That and the fact that they don't need to be replaced every certain amount of miles sold me on them.

 

I hear you on the trade-off. I was even thinking about doing a 224 with something slightly less than .600 lift just to stay in a safer operating range for beehives. Maybe even adding slightly more duration to offset. Or not, we're probably talking about a couple of horse power difference. If I was that concerned about every HP I'd be looking at different cams.

The responses in this thread have about 50/50 with good points for each option.

 

Also...the max lift for the PSI's is .625. The PAC's are probably the same.

 

Hmmm....don't remember getting a recommended change interval for the dual springs (either ones) that we've used. Back in the day, I do remember only some of the earlier single springs running higher lifts having a specified replacement interval. Most springs for milder lifts ranges I don't remember coming with a mileage limitation.

Some of the Mechanical or Material Engineers can correct me if I'm wrong (I'm a Civil Engineer), but I think the earlier spring issues were more a function of the materials being used than single vs. dual. Some of the earlier high-perf single springs needed to be made out of unique alloys to get a certain stiffness for .600+ lifts in a given spring diameter and height. Those same alloys, while offering the high strength (spring rate) needed did not have fatigue resistance like "lesser alloys" did. This would cause the springs to break after a certain number of cycles (hence the mileage limitation). This is similar to what happened in some building designs years ago when designers began specifying very high strength bolts for structural connections (more in my area of knowledge). The failures were traced to the bolts' alloys not having sufficient fatigue resistance, even though they were very strong. Basically as wind loads and stuff on the buildings "flexed the connections, the bolts were "loaded" and "unloaded" (cycled like a valve spring). The alloys didn't like that; they did great in situations where they applied a certain amount of load and then held it constant.

Today, there are different alloys and different spring designs and I'm not sure it is an issue like it was. If it still is an issue, then I would submit that a dual spring becomes a better alternative. A dual spring arrangement allows you to combine the strength of two springs. This means each individual spring can be made out of "lesser exotic" alloys to accomplish the same goal. Tried and true materials with OEM fatigue resistance (longevity) can be used so you don't have to swap springs every 30k miles.

To this day, I can't say definitively why I had my one spring failure. I really didn't dig into it that hard when it happened. I did look at the failed spring with a cheap (very cheap) magnifying glass and it looked like there could have been a slight material flaw where it broke. I also can't say exactly how many miles the car was driven with a broken spring. I can say it was driven at least for a couple of weeks which included at least one highway trip (couple hundred miles). At the time the break occurred, the car still hadn't been tuned. It would idle rougher and sometimes die at a stop because of the lack of tune, so it took me a little to recognize that it was actually not running quite right. The hard start and that it started acting that way all the time versus kind of periodically finally turned the light bulb on that I had an issue. I could have likely gotten away with just replacing the one spring. Instead, I chose to go with a newer dual spring (rated to handle a little more lift) for piece of mind....