I have always thought that the harder your valvesprings are, the more energy the cams need to use in pushing them down, and the more drag on the motor. So i would infer that this causes a slight power loss...

i always want to tell people to not get rediculously hard springs for relatively mild cams and rpm ranges to save power...

Does this make sense?? i could be just an idiot, but if anyone has some light they can shed on this it would be great....

thanks

 

friction is BAD...

 

Some motors make power into the 8+, 9+, 10+, 11+k rpm range.

How much spring pressure do you need? And what about boost?

How light are the rotating parts?

What kind of saftey factor do you like for accidential mishifts from 3rd-to-2nd-but-I-wanted-4th gear.

I'll give you guys a hint. Stock spring pressure offers none of this.

How hard is hard? 60lbs, 70lbs, 80lbs, 90lbs, 100lbs, 110lbs on the seat?

 

Rocket,

i understand that stock spring pressure wont take care of high rpms and huge cams with small clearances...


is there any way to get a rough estimate of about what pressure you will need based on weight of parts and rpm range?

do you guys have any method of determining a safe range, or do you just do it overkill to make sure things wont float?

thanks

 

I can tell you what I do, and my reasoning... however this isn't the BEST way to do it:

I run valve springs that I know have been run and tested for a over the maximum lift that my cams have - over 12.5mm of lift, and have the correct installed height/ recommended to me by the spring mfr for these cams.

I have even run "overkill" springs on stock cams - fortunately.

I have had a couple of mishap shifts which didn't do a single bit of damage... thanks to the valvesprings and timing belt I was using. I do not recommend 12k rpm's even on stock itr cams. Luckily, there was that element of overkill in the valvetrain and timing belt. *whew*

I gladly sacrifice a couple whp for that peace of mind.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Black R &raquo;</TD></TR><TR><TD CLASS="quote">I gladly sacrifice a couple whp for that peace of mind.</TD></TR></TABLE>

thats the way to go on a street motor, which is always gonna be what im building.... a few hp here and there in trade for insurance on thousands of dollars seems like a better deal to me.....

thanks for the input

 

It would seem that too much seat pressure is gonna cause wear problems aswell so keep that in mind for a street motor.

Diff springs can make up for lift in different ways. We compared the 2 different REV spring sets. High and low lift. The high lift I'm running has a physically shorter height, and a different thickness, and coil to prevent bind than the lower lift ones.

You need a set of springs that will compliment your cams because i couldnt see a looser high lift spring like the REVS being very good with smaller OEM type cams because of the slop.

 

so i guess a good rule of thumb is to just go with springs from whomever your buy your cams from (whenever possible)....

what do you guys think about running dual valvesprings vs. single, are dual springs really needed?

im trying to make this a learning thread...im asking very basic questions just to get all the info down for anyone who needs it....if every thread were like this...we could have some real good collections of info....

 

Has anyone ever thought of coating the cams/rocker arms/retainers/keepers/etc to try and reduce some of the friction? (much like one would coat a piston)

 

that sounds like a good idea in theory, except the side walls of a piston have less direct wear than the contact spot between the cam and rocker arm....it seems to me like it would just wear out pretty quickly....but as always, i have no experience with this, im sure someone can chime in with some real info....

love the avatar style for seinfeld...

 

60 - 65lbs on the seat and 170 - 185 at 0.500 is about the minimum I like for all motor. This will be good to 9200 rpms for most motors with commonly available camshafts.

High HP turbo 500+ should have over 90lbs on the seat.

Many factors go into rocker wear such, type of oil used, cleaniless of install, type of camshaft used, LMA binding, swaping camshafts etc.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Used2beAb16 &raquo;</TD></TR><TR><TD CLASS="quote">It would seem that too much seat pressure is gonna cause wear problems ...</TD></TR></TABLE>

im pretty uneducated on the matter but am under the impression too LITTLE pressure will cause more wear because the valve will bounce upon closing. this will factor into wear doubly because the heat transfer is reduced and even worse there can be a loss of compression during the bounce.

what do you guys think? rocket?

 

From what I've seen seat of the pants, cars run better with more spring pressure (90lbs on the seat).

 

good info rocket....

and mike, i have no physical experience here either, but what you say makes perfect sense...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike_belben@yahoo.com &raquo;</TD></TR><TR><TD CLASS="quote">

im pretty uneducated on the matter but am under the impression too LITTLE pressure will cause more wear because the valve will bounce upon closing. this will factor into wear doubly because the heat transfer is reduced and even worse there can be a loss of compression during the bounce.

what do you guys think? rocket?</TD></TR></TABLE>

whoops my mistake when saying "seat" pressure. What you say makes alot of sense you a little extra is better than a little less i suppose when your talking seat pressure.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rocket &raquo;</TD></TR><TR><TD CLASS="quote">60 - 65lbs on the seat and 170 - 185 at 0.500 is about the minimum I like for all motor. This will be good to 9200 rpms for most motors with commonly available camshafts.

High HP turbo 500+ should have over 90lbs on the seat.

Many factors go into rocker wear such, type of oil used, cleaniless of install, type of camshaft used, LMA binding, swaping camshafts etc.</TD></TR></TABLE>

Rocket, its very clear cut how the cleanliness and how the camshaft itself can affect rocker wear but what about oil? Have you noticed anyting personally with a specific type or weight?

 

im so confused. i am in the market for a valvetrain. i hear of people running 55 lb spring (OmniPower or RM) on the street but from what im am reading here this is too weak.
Is there a spring that is optimal for a all motor setup. I base what a buyfor my motor largly on what is said in the forums. I hope im not thread jacking

 

Look for an oil with good amounts of ZDDP.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18_Civic &raquo;</TD></TR><TR><TD CLASS="quote">im so confused. i am in the market for a valvetrain. i hear of people running 55 lb spring (OmniPower or RM) on the street but from what im am reading here this is too weak.
Is there a spring that is optimal for a all motor setup. I base what a buyfor my motor largly on what is said in the forums. I hope im not thread jacking</TD></TR></TABLE>

what kind of cams are you running? what's the max rpm that your shifting at? is your car street driven or track/drag only? my guess is your omni valvetrain is more than sufficient if you have a "street" setup..but hey, i could be wrong. fill us in though

 

im going to be running BC3 max rpm is 8500 and street driven that will see a little drag time.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rocket &raquo;</TD></TR><TR><TD CLASS="quote">Look for an oil with good amounts of ZDDP.</TD></TR></TABLE>

Thank you sir, do bike oils happen to have more of such a compound?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Used2beAb16 &raquo;</TD></TR><TR><TD CLASS="quote">Thank you sir, do bike oils happen to have more of such a compound?</TD></TR></TABLE>

I don't know about that, but I can tell you that Amsoil and Redline are known for using that compound.

 

i thought amsoil and redline didnt use that compound at all (zinc additive)
and were more along the lines of using moly base to reduce friction?


anyways, most of the people are only looking at one apsect of spring pressure (except probably rocket)

the MAIN goal is to make the valve follow the cam. if this ceases to happen, u are possibly going to loose power, and even damage the motor.

at the same time, u gotta look at the horrendous damage caused by OBX cams (incompatible material causeing excessive rocker wear) and in the end an excessively stiff spring could cause this same wear.

if rocket could, he had this video awhile ago showing valve spring oscillations in high speed photography and its pretty interesting to say the least about not only the stiff spring he uses in his "race" application, but also the interference fit designed into every set he sells, to help prevent these oscillations.

dont forget that a flat face stainless valve is alot heavier than a stock valve, and would need a stronger spring to control it.


i snabbed a little part of an article, if possible i would like someone (with a valve spring tester) to corraborate this, it would be pretty interesting

"You can go the cheaper route, adding only the intake cam. Keeping your stock (b18c,or b16) springs and valves. One reason this works is because the Type-R intake springs are actually slightly *softer* than factory dual intake springs. The reason is Type-R intake valves are lighter than regular intake valves, thus you don't really need additional stiffness from the springs since there is less mass for the springs to control. Type-R intake springs has oval sections which allow about .050"more lift at the valves before coil bind. But yet people who run stock intake springs on R intake cam don't have any problems... why? The problem maybe hidden. 1. with stock springs the valve springs are probably near coil bind, but not quite... so the springs will likely just fatigue a little faster... I would think that if there's coil bind there should be some obvious signs like cam wear or rocker arm wear or something. 2. the valve timing, it is pretty hard to tag the intake valves with the piston because it closes ABDC (after bottom dead center), even if you float a little your chance of valve tag is very little..."

 

[quote=johnzm]i thought amsoil and redline didnt use that compound at all (zinc additive)
and were more along the lines of using moly base to reduce friction?


anyways, most of the people are only looking at one apsect of spring pressure (except probably rocket)

the MAIN goal is to make the valve follow the cam. if this ceases to happen, u are possibly going to loose power, and even damage the motor.

at the same time, u gotta look at the horrendous damage caused by OBX cams (incompatible material causeing excessive rocker wear) and in the end an excessively stiff spring could cause this same wear.

if rocket could, he had this video awhile ago showing valve spring oscillations in high speed photography and its pretty interesting to say the least about not only the stiff spring he uses in his "race" application, but also the interference fit designed into every set he sells, to help prevent these oscillations.

dont forget that a flat face stainless valve is alot heavier than a stock valve, and would need a stronger spring to control it.


i snabbed a little part of an article, if possible i would like someone (with a valve spring tester) to corraborate this, it would be pretty interesting

"You can go the cheaper route, adding only the intake cam. Keeping your stock (b18c,or b16) springs and valves. One reason this works is because the Type-R intake springs are actually slightly *softer* than factory dual intake springs. The reason is Type-R intake valves are lighter than regular intake valves, thus you don't
We already discussed pressures at half inch lift (rocket)

I also mentioned that the some springs for high lift are physically shorter, with less coils to prevent binding with the large lift cams, and that for a mild setup they would be sloppy.

 

I have always been told that they are two of the few companies still using that compound, and that everyone else switched to the moly compounds.