alternative to Comp springs?

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70Hardtop

70Hardtop

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Hello, can anybody suggest some better springs, as an alternative to the Comp 995-16 (dual) I have bought? These were the recommended springs for the CC XE275HL-XE cam that I have installed in a 68 340 X head engine. Cam is a high lift hydraulic, 0.525/0.525. The springs are, on paper, ideal for this cam as they have a low coil bind number and fairly good open pressure of 336 pounds. Only 115 pound seat pressure though. Rate is 402 pounds.

The reasons I am considering other brand springs is because I measured all these springs carefully on a new Rimac valve spring tester and 70% of them were off the mark. Most were under, some by a lot, and a couple way over in the open pressure. Seat pressure was mostly all pretty close. Also, I believe in the motto: You Get What you Pay For, and these are pretty cheap springs, under US $100 at Summit. Even the labeling was shoddy, as the printed label on the end was saying open pressure of 376 pounds, which confused me for a while until I called up Comp and asked them, he said it was a printing error and the correct number was 336 pounds. (BTW, I bought these around 8 years ago, so I had forgotten all the numbers)

Another reason I don't like CC is because I emailed them twice about the poor test values of the springs and both emails were ignored. I have since read that other people have had poor customer service also.

I am looking at other brands like Isky, Crane, Crowcams, Manley and Lunati and ALL of them are twice or more this price. So I am thinking, how good can these Comp springs be for this price? - look good on paper but in the real world...

So I am wondering if anyone can recommend another spring which will fit Mopar and with similar specs as above? It seems there is not many springs around that will fit. Isky 6005 will fit but they are only 275 pounds and I was wanting well over 300 pounds with this engine and this cam.

Thanks
 
I have these on my build:
Trick Flow® by PAC Racing Dual Valve Springs TFS-16943-16
Valve Springs, PAC Racing, Dual, 1.550 in. Outside Diameter, 550 lbs./in. Rate, 1.068 in. Coil Bind, Pair

Not sure if that's to high but look at trickflow too.
 
Matts440 said:
PAC Racing Dual Valve Springs TFS-16943-16
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thanks for that lead. Yeah, way too high for mine (625 open and almost 300 seat at installed height of 1.7). Possibly they would be ok with the inner spring removed but I'm not spending $285 + shipping to Australia just to try and find that out! But yeah, I forgot to mention TF, I have two sets here, so I should have remembered.
 
Yea they have a .330 I think and summit had them for cheaper.

Just looked 340 lb spring and summit has them for $54.99. TFS-16942-16 but it's a 1.430 outer spring
 
Or these:
Valve Springs, PAC Racing, Dual, 1.550 in. Outside Diameter, 363 lbs./in. Rate, 1.140 in. Coil Bind, Set of 16

Summit $127
 
thanks , they sound better. The 1.43 OD is ok I think, that's closer to the mopar size than 1.55. Will check them out! Regards...
 
Have you considered beehives? I've been running Comp Cams beehives for years with good luck. I've gone to higher pressures, but still have a new set of 26918-16 that may fit your pressure range. They are nice because you don't have to worry about rocker-to-retainer clearance. You can juggle the installed height a bit with +/- locks or retainers. Not sure if you'd have to modify the spring seat any.
 
Are you checking them with the retainer?

Did you run them all down to coil bind 2 or 3 times before testing them?

Can you not balance the seat pressures with shims(and still have ample clearance from coil bind)?

If none of that works for you.... a PAC 1908 would work, but you’ll have to lose some installed height(-.050 locks) for 115 on the seat.
 
I,ll second the email issue. Filled a tech sheet for cam recomendation andstill no response. Lunati next day.

Tim
 
Locomotion said:
Have you considered beehives? I've been running Comp Cams beehives for years with good luck. I've gone to higher pressures, but still have a new set of 26918-16 that may fit your pressure range. They are nice because you don't have to worry about rocker-to-retainer clearance. You can juggle the installed height a bit with +/- locks or retainers. Not sure if you'd have to modify the spring seat any.
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I have heard about the beehive style but have never used them, no. They are the next generation style and those part number you said, I looked up, and the pressures are all good but looking at the dimensions, I would need to pull the heads and get the guides machined. I didn't really want to go that far. But good to know that you have had good experience with Comp springs, I can see by the price that perhaps this is more of a quality product. They are a huge company and I'm sure with their buying power they would be able to stock various lines of items of different quality for maximum profits. As I said, you get what you pay for and this is pretty true for anything in a free market.
 
PRH said:
Are you checking them with the retainer?

Did you run them all down to coil bind 2 or 3 times before testing them?

Can you not balance the seat pressures with shims(and still have ample clearance from coil bind)?

If none of that works for you.... a PAC 1908 would work, but you’ll have to lose some installed height(-.050 locks) for 115 on the seat.
Click to expand...

Yes I checked them with the recommended Comp retainer. No I didn't compress to coil bind 2 or 3 times. I wish I had thought to do that as I don't have access to the Rimac anymore. It is owned by a Top alcohol racer in a machine shop. And the same goes if I wanted to use the shims, I would need it for a quite a few hours to do every spring several times and log it separately etc. Re, that PAC spring, it looks to be a little lighter than the comp but probably a better quality. But I am also wondering how many valve spring manufacturers are there? Would every company make their own springs...? I doubt it, they most likely outsource production to spring manufacturers with contracts based according to their own requirements and specs. That 1908 PAC is a perfect Mopar size but is a little light unfortunately and also don't think it would handle the 0.525" lift, looking at the heights given on Summit... even if I didn't eat into some of the installed height to get more pressure.
 
Tims 66 Cuda said:
I,ll second the email issue. Filled a tech sheet for cam recomendation andstill no response. Lunati next day.

Tim
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Thanks for your experience. Yeah, that's the trouble with (a lot, not all) big companies. They don't really care if they lose the odd customer here and there, they know they have to do something pretty major to go broke. Even if they don't have the staff to service every question, it still comes across as crappy service. When I rang them to ask about the misprint on the box (again, more poor quality control), the guy I spoke to wasn't overly helpful or enthusiastic - just get me off the line and onto the next person. Where's the interest gone these days? Same as when I emailed Schneider cams - sent a friendly email asking some questions and my application - got a half assed ("arsed" - Australian spelling) general reply with no interest at all, totally unhelpful. These guys don't realise that by saving a few minutes on writing and enthusiasm for their customers, they are actually doing more damage to their reputation in the end.
 
Tims 66 Cuda said:
I,ll second the email issue. Filled a tech sheet for cam recomendation andstill no response. Lunati next day.

Tim
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70Hardtop said:
I have heard about the beehive style but have never used them, no. They are the next generation style and those part number you said, I looked up, and the pressures are all good but looking at the dimensions, I would need to pull the heads and get the guides machined. I didn't really want to go that far. But good to know that you have had good experience with Comp springs, I can see by the price that perhaps this is more of a quality product. They are a huge company and I'm sure with their buying power they would be able to stock various lines of items of different quality for maximum profits. As I said, you get what you pay for and this is pretty true for anything in a free market.
Click to expand...

I was thinking that if the guide step was machined away to accommodate dual springs, you would have enough seat room for the beehives. If there were any "centering" concerns, a spring cup would help.

Although I've had good luck with their beehives, I have to admit that I haven't had the luxury of individual spring testing, just going by their charts. The only problem I've had in my race application was several years ago. I found a partially broken retainer and others kind of beat up after a few seasons. I shimmed them for 20+ more lbs of open pressure and everything seemed better, including maintaining valve adjustments.
 
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Just so you guys know, most of Comps springs are sourced from PAC. Many other companies get them there as well, so just going to a different brand doesn't mean it's a different spring.
 
The specs in the respective catalogs are
402lbs/in for the Comp 995, and 417lbs/in for the PAC 1908.

The 1908 is also listed as usable for up to .650 lift, so I don’t see how that .525 lift cam would be a problem.

“If it were me”, I’d set them up at about 125 on the seat(about 1.640 IH) which would put them at a nominal [email protected] lift.
 
MOPAROFFICIAL said:
Comp sucks, mostly.
Their springs lose more pressure than any others I've run.
K motion 700 [email protected]/[email protected] rate 465
But what stem size would help' to get retainers that work'. Will need to size the guide to locate'em.
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Interesting to see another person's experience - I looked up the K700, all great with them except the size, had a look at dimensions and would have to machine the guides. It's the same story with a lot of springs, there's not that many that will just fit straight onto the mopar head. Stock guides mopar are just under the inch, so about 0.995". The ID (outer) on many springs is under that. Heads are all bolted down, I just don't want to take'em off and strip down for that. I have some Trick Flow ones to look at which look pretty close.

I appreciate the replies though, has given me a good range of springs to consider.
 
B3RE said:
Just so you guys know, most of Comps springs are sourced from PAC. Many other companies get them there as well, so just going to a different brand doesn't mean it's a different spring.
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yeah, that's what I thought as well, I mentioned something like that in a previous post, it's the same with lifters as well.
 
Stock guides mopar are just under the inch, so about 0.995".
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That step needs to be machined down so the inner spring sits flush with the outer spring.
The only aftermarket spring Ive seen that’s designed to have the inner spring sit on top of that step is a Hughes 1111.
 
PRH said:
The specs in the respective catalogs are
402lbs/in for the Comp 995, and 417lbs/in for the PAC 1908.

The 1908 is also listed as usable for up to .650 lift, so I don’t see how that .525 lift cam would be a problem.

“If it were me”, I’d set them up at about 125 on the seat(about 1.640 IH) which would put them at a nominal [email protected] lift.
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Hey, yeah, I had another look, you are right - sorry I was looking at the "open height" given on Summit which is 1.2 something and didn't see the coil bind height which is on another tab (in 'Applications', dunno why they don't put all the info in the overview - stupid -) The coil bind is a lot under the open height pressure, I assumed the coil bind was much higher, so yes, they would easily take the 525 lift even installed at 1.62. And they are good pressures for my cam. Good price too, however I am wondering that if Comp source their springs from PAC, maybe they are exactly the same, with just slightly different rates/specs etc! Not sure how they get all the various numbers to change, the metallurgy would have to be slightly different surely. Looking at the prices and sizes, which are pretty close to each other, I can only assume the Comp and these PAC would be close in other ways as well.
 
Matts440 said:
Yea they have a .330 I think and summit had them for cheaper.

Just looked 340 lb spring and summit has them for $54.99. TFS-16942-16 but it's a 1.430 outer spring
Click to expand...
Matt, just checked out these springs on Summit - and I just realised I already have a set of these. I wasn't going to use them because they are a bit light for this higher lift cam and higher revs if I want. These are 285 open pressure, I was wanting mid 300s. But I will use these on a 273 build I am doing.

Summit have this annoying thing where they put some of the critical specs on another tab, basically another page. So when looking at half a dozen different springs, you can overlook that. They should put all the spring specs in the overview so they can all be seen in one glance.
 
True on stuff like that for all the specs I just go to the manufacturer web page then cross the numbers over for the price.
 
Locomotion said:
I was thinking that if the guide step was machined away to accommodate dual springs, you would have enough seat room for the beehives. If there were any "centering" concerns, a spring cup would help.

Although I've had good luck with their beehives, I have to admit that I haven't had the luxury of individual spring testing, just going by their charts. The only problem I've had in my race application was several years ago. I found a partially broken retainer and others kind of beat up after a few seasons. I shimmed them for 20+ more lbs of open pressure and everything seemed better, including maintaining valve adjustments.
Click to expand...
You have an advantage with racing experience, so a lot of things are 'second nature', you can really see how things perform under high stress. I never thought I would hear of a retainer breaking, they must really get a pounding. It would be interesting, with valve springs, for you to check all of a set of springs against the factory numbers, then do a season of racing, extended high RPM etc, then measure the springs again and see how much pressure they still had.
 
They do lose pressure, which was likely contributing to valve float. I can't imagine what else it could have been. That's when I replaced the springs with new ones, but at higher pressures. I just don't have a spring tester handy to help figure out their life cycle and rate of degradation. My engine builder is a couple of hours away and I don't visit too often. But they do last several seasons, even with the Stock class cam profiles, which tend to be as aggressive as you can get with composite flat tappet lifters. The only cam specs that are limited are lifters (flat if it came flat OEM) and cam lift. Duration and opening/closing ramps are much more aggressive than typical performance cams.

There are different materials and processes (cryo & micro finishing/polishing) which can prolong spring life. But it may not always be feasible. Some race combos replace springs very often, depending on the application, rpm and cam profile, even with better metallurgy & treatments.
 
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