Johnnystock

iTrader: (6)

After one season, I feel the car is kinda lazy compared to when the valvesprings were freshly installed in april. I put down 568rwhp back then, hp still climbing to 7900. Dyno rpm signal problem, could not get 7200 rpm + hp numbers.

Any how, the car has a solid roller low lash with 1.8 ratio T&D(geometry checked no need to shim or machine on the FED TFS heads 267cc), car has 720' 702', dur 239/253. Cold lash 0 and .010 hot. I run 3/8s pushrods, swipe pattern is good. Lash checked hot n cold good.

Springs are PAC 1209x, Ti retainer, 1.78 installed height. Specifications;

• Part# PAC-1209X
• Name PAC-1209X RPM Series Dual
• SKU PAC-1209X
• Alt Part# PAC-1209X-16
• Description RPM Series LS Round Wire Dual Valve Spring
• Outside Diameter 1.324
• Outer Spring ID 0.950
• Middle Spring ID N/A
• Damper No
• Inner Spring ID 0.680
• Install Height 1.800
• Load at Installed Height 160
• Spring Open Height 1.100
• Spring Open Load 510
• Recommended Valve Lift 0.750
• Spring Rate (lbs/in) 500
• Coil Bind (max) 1.000

I figured the springs have more pressure and guess the springs life are shortened, I have 4000miles on them and 200 plus runs at 7900.

Anyone feels free to enlight me on what springs would be better. I thought maybe Manley Nextek 221421 btu they have less springs rate (435) but a little bit more open (515) and installed (165) pressure, and more lift rated 800'. They do have more room for coil bind at .900 insteat of 1.000 with the Pac,

How much pressure/load is too much?

Just swap em out and be ok with it?

G Atsma

Have you retested the springs?

Johnnystock

iTrader: (6)

No. That would be a start I guess.

Corona

Hmmmmm 🤔
Doesn't each cam lobe require a different open spring pressure?
Yes.
So each cam needs a spring to match😉🤐
My .730 lift cam may require a open spring pressure of 670 for example while Marlin for example with .730 may only need 525 open spring pressure.
Two different springs🤔
Refer to cam manufacturer on its Lobes for springs.😉🤫🤐

TurboBuick6

iTrader: (2)

This^^^^. We need to know what your cam manufacture is recommending for seat and open pressures. Need to verify that is with your rocker and not a stock rocker.

You will not be able to just "swap" springs out. You will need to set them up for the correct height, regardless which direction you go. This isn't a 6,500rpm street car, you are getting too hot for just part swaps without setting parts up.

Che70velle

iTrader: (6)

The 1209x’s are rated at an installed height of 1.800”. If you’ve set them up at 1.78” installed height, then you’ve got a little more spring than advertised. Someone used a .020” spring shim when they set this up. I see no issues with you changing them yourself, as long as you use all the hardware that’s there, and seat the locks properly. Of course if you don’t feel comfortable doing this, have a shop do it by all means. Either way, with 200 passes and 4000 street miles on a solid roller setup, I guarantee you it’s time for a new set of springs. If your running Ti retainers, I’d go with a new set of them also. Ti has a limited number of allowable heat cycles and gets brittle with age. You must know the exact retainer your using now, because using a different retainer will alter the heights and throw off everything.

Johnnystock

iTrader: (6)

Got the cam from a friend, who was running this cam with same set of springs. Ill double check that.

I assembled everything myself. I set up this as it is and the height was 1.780 with the seats from FED (that originally came with the 660' springs set and Ti). So I just installed the Pac with those seats and checked the clearance/ installed height. It varied from 1.778-1.785.

I measured everything. I dont think the seats or Ti retainers worn so much that the original height and other measurements changed that much. Ti wont worn as much as steel iirc. They will go out. I will get a new package to ensure all is new.

Beeing a low lash, I wouldn't think Cam Motion recommended different springs on exh/int lobe. But I'll have a look.

Thank everyone. Sounds like I have to change springs after 2-3k miles on the setup. I'll removed a set and measure and look how things are. I was driving today and went WOT and its like sometimes the hp is all there and sometimes not. Really weird.

Ti retainers are FED. I asked them about the setup and they said their Ti retainers would be ok in my setup.Just to clear, the heads are bare casting TFS 255cc then fully custom CNC'ed by FED to their own 267cc program. So maybe the springs pocket are a bit deeper than stock so the installed height is lower, idk. Texas speed have a cheap 1209x kit for 379$ with seats and Ti retainers..!!

rkupon1

iTrader: (3)

Johnny! Whats up, were you datalogging when the ho starts going away? Is it intermitten or happening every wot pull? That seems pretty aggressive wear n tear on only 2-3k miles no? FED say anything?

Johnnystock

iTrader: (6)

I did datalog and sent it to Pat G and no timing were really pulled or nothing was wromg to explain the power loss.

You tell me; solid roller low lash, 720' 702', 7900 rpm, 1.8 shaft rockers, how long is it supposed to last?

I bought PAC off Summit Racing, FED did not spec me the 1209x. I asked em if it was ok to run their Ti retainers with the PACs and they said yes. I asked if it was safe to run 8000 rpm with their Hollow int valves with solid roller low lash setup and they said yes. Nobody spec'ed me anything, I came up with those springs, since they're pretty much the only "non-race" doubles that can take .750' and have 500 load and around 500+ press, which was what I should shoot for 7900rpm and solid roller.

Corona

You still didn't Answer the ?
For any lobe there's a Given open spring pressure. And I re spec'ed my own cam, cause my Dumb 🐴 purchased 1.8 rocker arms for a 1.7 cam.
And I ask again, so for the lobes picked by: U < what is or was the recommendation for open spring pressure on .....
If u don't know this how does one pick a spring?
Answer is look at the lobe numbers used call the cam manufacturer. Ask so what's the recommendation for spring pressure on _______ lobes.
Pick spring accordingly 😉🤫

Corona

To simple🤔
my cam reads 260/274 @ .050 738 lift 113+4

Pac springs list all read? 🤫😉🤔🤐😏
Max lift .750
https://www.racingsprings.com/index....ring-4623.html

Max lift .750
https://www.racingsprings.com/index....ring-4617.html

Max lift .750
https://www.racingsprings.com/index....ring-4618.html

I know which spring I choose based off the post above.. 🤔 I got the most spring pressure used of the 3 😉🤫
Fill the Damn (Thang) = cylinder🤣
My Damn (thang) = °Cam) Needs some more Seat & Open Pressure 🤤 valve springs (if I picked any other spring besides the 1$t one.) Based on the lobe choosen and the cam manufacturer rating on?🤔😉 Open & seat Spring pressure ✅🤫

Johnnystock

iTrader: (6)

Cam card

Well I dont know what they recommend. I went with suggestion from TSP and other knowledgeable guys, and the guy who ran the cam before me.
I lile the 1238x springs, but labeled as race only springs, is it alright for a street setup?
​​​​​​I ask Cam Motion what they would suggest. They have 419$ extreme dual that have the same spec as the PACs 1209x.

Their low lash lobes do well with regular 660' springs when you keep lift in check. Cam Motion gets 20k miles without checking or swapping springs in a tame setup.

I wonder if they have many solid low lash lobes.

Corona

U need to contact who Ever made the cam with the lobe numbers used on the cam card. That simple. They'll give you a reference spring pressure and or valve spring. If you've got a reference spring from the cam manufacturer, find any spring with the same general max lift and open spring pressure

Corona

Who did you purchase the cam from?
What's the lobe numbers listed?
Who's cam Lobes are being used?

Johnnystock

iTrader: (6)

Low lash solid roller cam motion. I am not aware they make more than ome low lash lobe.

Corona

Call Cam Motion ask 4 Steven or Bobby ..
They need 2 no the Lobe numbers for your cam. Which generally are the: example Cam reads 5408/6808 hr 113+4
5408 is the intake lobe the 6808 is the exhaust.

They will give you the recommended springs for your cam and recommended seat and open pressure. So then u could pick your own.

This Message is brought to you by Smokey B.
Rule #278564. U must have a recommendation for springs if you purchase a cam. Which includes seat and open pressure.
Not just, oh it says .700 max lift for springs and my cam has 680 lift. Yeah that sounds great. 🤔
That's BS and the incorrect way to purchase valve springs.🤫😉

Corona

BTW I couldn't read any specs or basic information on that cam with what was shown. Call Cam Motion as they don't list all there Lobes.
Bobby made me a 800 lift Low lash SR so you thinking all Low lash lobes are the same. ....Wrong!

Johnnystock

iTrader: (6)

My friend who had the cam was running softer 1208x springs since he had 1.7 rockers. Why I went with 1209x with higher lift cause of 1.8 RR.


Cam card better pic

bortous

Can I call you for a chat?

Corona

Call Cam Motion..get there recommendation.....

This is sad. U Scared to talk to the people who made the cam. .