Stem seals for dual valve springs

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MopaR&D

MopaR&D

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I just got a set of dual valve springs w/dampers for my 318 and the valve stem seals that came in my Fel-Pro gasket set won't fit inside the springs. Anybody know what kind I need to get that will fit?
 
You need to do three things to run dual springs... 1. The tops of the guides must be reduce in size so positive seals can be run. 2. The space the springs sit in in the head, called the spring seat, needs to be machined flat so the inner spring is not sitting on a step. 3. You will need new retainers and matching locks so the springs are held properly.
 
I swear to God, I'm ready to push this car into the street and light a fire under the gas tank. How much will that crap cost? I'm already almost out of money...
 
I guess my question is what kind of cam your running that needs dual springs?

Another words are dual springs really necessary?

Aren't there single springs that would work?

I'm learning so I am curious.
 
Well, the cam I got is the Lunati Voodoo 256/262 and the springs they recommend are dual springs with dampers (P/N 73949). I posted a thread a little while ago asking if I really needed that much spring and the general consensus was that I should follow whatever the manufacturer recommends, which I did.
 
I'm just guessing here but looking at the chart I have.... Comp Cam 942-16 single springs might work.

moper?

Your cam lift is .454/.475 correct?

Your springs Lunati 73949 specs:

Description Dual w/ Damper
OD 1.440''
ID 0.750''
Seat Load,Height/Load 1.650''/120
Open Load, Height/Load 1.250''/265
Coil Bind 0.950''
Max Lift 0.640''


Comp springs 942-16:

Seat Load 115 @ 1.700
Open Load 284 @ 1.200
Coil Bind 1.125
 
Mullin, I'm following you.

kid, I have to apologize to you... I dont use a lot of Lunati stuff, and as such, I was not aware that they spec the same double spring for every cam part number... from mild to wild, even tho the description says you can use factory springs. I dont think factory springs will work well with this fast rate of lift tho.

What I would suggest is not the Comp 942s. I think they would have a little much on the seat which is no big deal... but a lot more over the nose. Like 100lbs plus by quick thinking. I would use the Comp 901s, with a small shim under them to get them right in the spec of 120 on the seat and 265 over the nose. They will work with umbrella seals and your original retainers and locks. I have them on my 360, with the Comp XE262 cam. I dont run shims however. I would get some .020 shims and run the 901-16s.

Once again, sorry kid... why Lunati would run that same spring for a 213°@.050 and a 252°.050 I have no idea. That's a ton of head work for a way overkill spring.
 
Oh well I tried kid

Still learning how to do this stuff.. thanks moper.

I'd do the 901s and send the others back.
 
Oh, thank you guys, you're life savers. No hard feelings Moper, I was just annoyed by the whole predicament. I suppose I'll ship those springs back to Summit and get the ones you guys suggested.
 
I get valve float @ 5100 rpm with Crane 99835 springs on that exact cam. Just thought I would let you know. Since you're running that cam on a 318, I would think power would peak @ 5400 rpm. I'm thinking that Lunati knows what their doing. You could always give them a call too.

Keep in mind I'm running 2.02 intakes which are heavier and 1.6 ratio rockers.

Spring Specs:

Part Number: 99835-16
Outer Diameter Top 1.500
Inner Diameter Top 1.086
Damper YES
Seat Pressure @ Installed Height 113 lbs. @ 1.600
Open Pressure and Height 280 lbs. @ 1.150
Coil Bind 1.000
Average Spring Rate 412 lbs./in.
Maximum Net Lift 0.565
 
ramcharger said:
I get valve float @ 5100 rpm with Crane 99835 springs on that exact cam. Just thought I would let you know. Since you're running that cam on a 318, I would think power would peak @ 5400 rpm. I'm thinking that Lunati knows what their doing. You could always give them a call too.

Keep in mind I'm running 2.02 intakes which are heavier and 1.6 ratio rockers.
Click to expand...

I think I'd rather give up some RPM than pay extra for machining. I would probably do it but I literally have no money left. After I get the head surfacing/valve job/cleaning done I'll have about $150 left which I'll have to use on an intake manifold. If I want any more money I'll have to run around town looking for a job (which I will probably look for anyway, but nobody's hiring from the economy) and wait another month or so, which I'm REALLY sick of doing. This car has been sitting in my garage since October and I've been bumming rides since then. It wouldn't be that bad either if everybody I knew didn't give me that "Why are you wasting your time and money on that old piece of junk car" look (especially my dad), which gets really annoying after a while. Sorry about the rant, but I'm reaching the end of my wits with this crap (no offense to any of you guys).

EDIT: BTW I'm running itty-bitty 1.78" intakes with stock 1.5:1 rockers.
 
OK...... But you'll be sorry, lol. Just giving you some crap, don't take it personally. :) Sometimes you have to comprimise. You'll probably be putting in the dual springs next winter. Like I said, I'm running heavier valves and more rocker ratio so your results will vary.

As far as people wondering why you do what you do with these old cars, better get used to it. I'm 43 and I still hear that ****. I just tell 'em golf is for **** and I don't have to wait for fkin "tee time" to have fun. They usually shut up after that. Don't tell your Dad that though...
 
I really would prefer to do it right, but I don't have the capability for it at this point. Come to think of it, I think it's fine that I might have to do that next year as I plan to port my heads in the future anyway. In stock form I don't know if these heads will make much power past 5500 RPM anyway. Hell, this is my first time even inside an engine, so there's probably a chance I'll blow it up when I go to start it anyway.

What's funny is that my dad doesn't golf or do any of that stuff. Come to think of it, my dad doesn't really have any "hobbies" of his own besides martial arts and working out/running (blech, who wants to do that???). He's a very "practical" man, and finds no point in spending money on anything besides the bare essentials; obviously, he doesn't think very highly of me dumping thousands of dollars into an old "muscle" car just so I can get it running well. My friends just don't get it either. I've come to the conclusion that you either "got it" or you don't; if someone can't imagine how spending four hours under the hood of an old truck trying to pry off a pair of 50-lb. cast iron cylinder heads from a dirty, greasy engine could possibly be fun, then they obviously could care less about how fast their car goes or even what car they drive.

EDIT: If the single springs w/dampers have the same specs as the dual springs w/dampers, what's the difference anyway?
 
MOPEkidD-3 said:
I really would prefer to do it right, but I don't have the capability for it at this point. Come to think of it, I think it's fine that I might have to do that next year as I plan to port my heads in the future anyway. In stock form I don't know if these heads will make much power past 5500 RPM anyway. Hell, this is my first time even inside an engine, so there's probably a chance I'll blow it up when I go to start it anyway.

What's funny is that my dad doesn't golf or do any of that stuff. Come to think of it, my dad doesn't really have any "hobbies" of his own besides martial arts and working out/running (blech, who wants to do that???). He's a very "practical" man, and finds no point in spending money on anything besides the bare essentials; obviously, he doesn't think very highly of me dumping thousands of dollars into an old "muscle" car just so I can get it running well. My friends just don't get it either. I've come to the conclusion that you either "got it" or you don't; if someone can't imagine how spending four hours under the hood of an old truck trying to pry off a pair of 50-lb. cast iron cylinder heads from a dirty, greasy engine could possibly be fun, then they obviously could care less about how fast their car goes or even what car they drive.

EDIT: If the single springs w/dampers have the same specs as the dual springs w/dampers, what's the difference anyway?
Click to expand...


Listen .... I went down the same road. I was talking to my local machine shop owner/operator and he told me I didn't need dual springs and then told me what to get. I have yet to have any problems, valve float etc... The cam companies want you to buy the duals for some reason I guess because they can make more money off of them. Read moper's last post " why Lunati would run that same spring for a 213°@.050 and a 252°.050 I have no idea. That's a ton of head work for a way overkill spring."

You'll be fine! Just because people say "Oh you better run what they recommend" is bullshit! moper is probably been doing this stuff longer than I have been alive.. think he would recommend to you a different spring if it meant it would not work correctly? I don't think so. My local machinist has been doing this stuff a while also and has his own drag car in which he said he has $15,000 just in the motor.
 
Ax, dual springs have different harmonics than single springs do. Due to the rate of lift and profile of the ramp, the single springs may end up in a "harmonic" due to the stresses induced into the valve train by this particular cam.

I can tell you my valves DO float @ 5100 rpm with the above Crane single springs.
 
LOl... I should start by saying two things... I'm not THAT OLD!!!! and I am a 20 handicap for golf :D. Cars need to have thier place in ones life. I recently sold most of my stuff and all my cars for that reason. I plan to golf more this year.

ram - I tink I grasp the harmomics, I just dont think it's that huge a deal with such a mild grind... I also don't believe you should have float... What height were those Cranes installed at? You notice I said he should run some shim to get the "lesser" spring into the range we need it. Also, did you test the spring pressures on them? I KNOW MP has some bad spring issues. They go weak in a very short time with the larger or aggressive ramp cams. I've never had trouble with Comp or Crane springs, but there's always a first time. I'd like to hear BJRs take on this thread too...
 
moper said:
and I am a 20 handicap for golf :D. Cars need to have thier place in ones life. I recently sold most of my stuff and all my cars for that reason. I plan to golf more this year.

Oh crap, I knew I'd offend someone with that, just not so quickly, lol! Fine then moper, sell all your cars, buy a nice set of clubs. I'll be in the shop. :-D Easy for me to say as cars are not my living anymore, makes it a lot more fun. It's how I decompress after work.

ram - I tink I grasp the harmomics, I just dont think it's that huge a deal with such a mild grind... I also don't believe you should have float... What height were those Cranes installed at? You notice I said he should run some shim to get the "lesser" spring into the range we need it. Also, did you test the spring pressures on them? I KNOW MP has some bad spring issues. They go weak in a very short time with the larger or aggressive ramp cams. I've never had trouble with Comp or Crane springs, but there's always a first time. I'd like to hear BJRs take on this thread too...
Click to expand...

I did not test the springs before or after intial installation, so weak springs are definitely a possibilty. The springs were installed @ 1.590 + or - a few thousandths. Yes, I did notice that you mentioned shimming the springs some. :)

I agree moper, I most certainly would not think that a cam this small would do this, but there it is.

The fast rate cam plus the 1.6 rockers, possible weak springs and heavy 2.02 intakes could all be contributing to my valve float problem. This cam stops pulling at about 5K anyway in my combo so i'm not all that worried about it although I could possibly see picking up another 200-300 usable rpm if I were to resolve it. If the engine was in my Duster, I'd yank and test them.

Where is BJR? lol!
 
You sure its valve float and not a fuel delivery problem? Just wondering how you know its valve float?
 
moper said:
LOl... I should start by saying two things... I'm not THAT OLD!!!! and I am a 20 handicap for golf :D. Cars need to have thier place in ones life. I recently sold most of my stuff and all my cars for that reason. I plan to golf more this year.
Click to expand...


I didn't mean it like that... I just been under the impression that you've been doing this for a long time that's all.

I'm not good at golf... I tried hitting that little ball and when I finally did I sliced it!

I gave the club back to my friend and said "Nope ... I can tell right now that this ain't for me!":-D
 
340sFastback said:
You sure its valve float and not a fuel delivery problem? Just wondering how you know its valve float?
Click to expand...

Holley electric fuel pump, 3/8 pickup and -6 AN line, dual feed double pumper and the problem does not respond to jetting at all. 5.1K on the button every time. I'd say the only other thing it could be is the MP distributor (phasing problem maybe?). I'd like to try a MSD or Mallory just to be 100% sure.

Tach doesn't wig out so it's not a primary ignition problem.
 
What kind of ignition system are you using? I went straight from points to a Mallory HyFire-6A box, canister coil, and Chrysler reman'd electronic dizzy. I did notice a difference in throttle response and the low-end got a little more "crisp". Of course it wasn't that big of a difference because my engine was sick anyway, but with an engine as nice as yours you should give it a shot.
 
I'm using the Mallory 685 Hy-Fire VI and a Mopar Performance distributor. I figured the MP distributor should be good to 6K. I wish to high heaven that I had a distributor machine. I'm still waiting for one to show up on craigslist.

Just found this on the 4 seconds flat website:

"Cap/Rotor Phasing:

This is another part of the ignition tune-up that is almost never addressed. So called Super Tune shops are aware of this inherent problem with Mopar distributors (and others) and it's one of the first things they check.

Simply this is getting the spark signal to the plug by aligning the rotor and cap contacts so the spark travels to the plug at the instant that the two components are aligned or phased.

The Mopar distributors almost never do this, the rotor is either not yet at the contact or it has long since past it's optimum point. What this does is cause the spark to have to jump or arch to the cap, this causes heat energy. If we go back to basic physics we know that "Energy cannot be created or destroyed it can only change form" so what we do here is convert electrical energy to heat energy and effectively reduce the power of the spark as RPM increases and pressure in the cylinder increases causing a higher resistance for the plugs the spark efficiency is drastically reduced...result....poor performance...lost HP and tork.

The cause of this phasing problem is multiple, the biggest thing we find is the vacuum advance plate on a Mopar distributor is really a poor design allowing it to tip and wobble in the distributor housing....when you get your distributor back from us you'll find that plate welded solid and the advance curve is controlled by the weights and springs. Bad bushings, worn gears, poor factory tolerance, cheap caps and rotors can all contribute to or multiply the phasing problems.

It's very common to find a Mopar distributor with the phasing so far off that at around 5000 RPM and up the rotor will get confused and start arching to either the contact ahead or behind it's position....ever heard this "I have a high speed miss I just can't find".....
Of course the investment in a high dollar MSD or similar type distributor is a solution and after we run them up on our machine, calibrate them to your specific engine they are excellent, but....most of us here are using our cars as daily drivers and go blast off a few 1/4 passes on the weekend. This is why we work over the stock distributors and or the Mopar Performance distributors (which are better for more performance orientated cars) and make them work to spec or "Blueprint" them for a fraction of the cost."
 
One of the things i dont like about FBO... He's got the idea, but I think he's talking to hear himself talk. I think it was Rick Ebooger who was selling the reluctors with like 8 spots for the lock pin to help address this. It's easy to check. Drill hole above the #1 terminal in a used cap, and use your timing light to see what it's doing in there and at what rpm. I also read the carbon marks in the caps and rotors to see where they end up. It's not as prevelant as Don says, but it happens.
 

Thanks moper, great idea. I'm going to check this out this weekend. I'm sure I've got an old cap laying around.
 
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