valve spring choice for a 34-711-9 puller cam roller

i have set iron heads and would like to set them up for this cam.
would the 999-16 work for this .633# spring rate 215# seat pressure . or too light
i already have the retainers and cups for the 1.55 outer size spring so was hoping i could stick to this size . max installed height is 1.9 unless i put differant valves in .so ..
thanks

That spring is 27 pounds lighter open ( from the spec.'s you gave ) than the 660 pounds open on the 991-16 spring that cam calls for. On the seat the 991's show 210. I say go for it.

https://www.jegs.com/i/COMP-Cams/249/34-711-9/10002/-1

https://www.cspracing.com/comp-cams-991-16-valve-springs-1-625in-chr-sil/comp-991-16/

https://www.cspracing.com/comp-cams-999-16-valve-spring-1-550in-h-11-asse/comp-999-16/

The Spring Rate shows to be 7 pound less.

The numbers I listed are out of the Comp Cams Catalog and the dual spring called for that cam. The triple spring also listed, 948-16 is much heaver, and is likely for extended high RPM pull truck use.

supervel45 wrote:That spring is 27 pounds lighter open ( from the spec.'s you gave ) than the 660 pounds open on the 991-16 spring that cam calls for. On the seat the 991's show 210. I say go for it.

https://www.jegs.com/i/COMP-Cams/249/34-711-9/10002/-1

https://www.cspracing.com/comp-cams-991-16-valve-springs-1-625in-chr-sil/comp-991-16/

https://www.cspracing.com/comp-cams-999-16-valve-spring-1-550in-h-11-asse/comp-999-16/

The Spring Rate shows to be 7 pound less.

The numbers I listed are out of the Comp Cams Catalog and the dual spring called for that cam. The triple spring also listed, 948-16 is much heaver, and is likely for extended high RPM pull truck use.

thanks i actually called comp today and they said i could run those springs same thing as long as rpm under 6500 said should be fine

You're Welcome. Those H-11's are some pricey bastards, that's for sure. I assume you already had them, hopefully.

No I do not but I might be better off cutting my heads and going to
A 1,.95 seated height spring

Lots of things you could do. +/- Keeper's, Retainers, and other springs. Might look and see what PAC has.

FMR, I guess all the prices are stupid.

https://www.racingsprings.com/media/wysiwyg/2020_Master_Catalog_FINAL_Web.pdf

PAC 1243 is close.

https://www.jegs.com/i/PAC+Racing+Springs/278/1243-16/10002/-1?gclid=CjwKCAiA9qKbBhAzEiwAS4yeDSDWhJHnbuXEx7c9h3ivolZOZ_xPlLqtt6JgRkYUig_Qp2VnXLXfyhoCrr8QAvD_BwE

Have Fun.

supervel45 wrote:FMR, I guess all the prices are stupid.

https://www.racingsprings.com/media/wysiwyg/2020_Master_Catalog_FINAL_Web.pdf

PAC 1243 is close.

https://www.jegs.com/i/PAC+Racing+Springs/278/1243-16/10002/-1?gclid=CjwKCAiA9qKbBhAzEiwAS4yeDSDWhJHnbuXEx7c9h3ivolZOZ_xPlLqtt6JgRkYUig_Qp2VnXLXfyhoCrr8QAvD_BwE

Have Fun.

thank you very much . those are only allow for .700 lift though

When you subtract lash, pushrod angle and flex you will be at .700 lift or less.
The coil bind is a 1.070" in the PAC catalog for them. The Comp Cams recommended springs for your cam, the 991's are at coil bind at 1.125". Do the math on the installed height ( 1.950" vs 1.9" ) and .055" difference in coil bind, I come up with .005" difference.


https://www.superformance.com.au/assets/files/Brands/Lunati%20Camshaft%20Catalogue.pdf

Page 289 and 293 has the Lunati dual springs. They seem to be around $350.00.

The Pac 1243 is a very good spring. I use and sell a lot of them. Same spring Ford uses in the M-6049-SCJB cylinder package.

maverick172 wrote:

supervel45 wrote:FMR, I guess all the prices are stupid.

https://www.racingsprings.com/media/wysiwyg/2020_Master_Catalog_FINAL_Web.pdf

PAC 1243 is close.

https://www.jegs.com/i/PAC+Racing+Springs/278/1243-16/10002/-1?gclid=CjwKCAiA9qKbBhAzEiwAS4yeDSDWhJHnbuXEx7c9h3ivolZOZ_xPlLqtt6JgRkYUig_Qp2VnXLXfyhoCrr8QAvD_BwE

Have Fun.

thank you very much . those are only allow for .700 lift though

That's .700" net lift....after lash is subtracted. .727" lift minus .024" lash = .703" net lift.....as an example.

Oh ya but does lash not tighten when engine warms up?

A very small amount with aluminum heads. What I was getting at with the PAC springs and the recommended Comp. springs there is really no difference in coil bind. You are .130" from coil bind with the PAC's and .125" with the Comps at .700" lift from coil bind, at their respective installed heights.

You get more lash hot, less lift.

maverick172 wrote:Oh ya but does lash not tighten when engine warms up?

More lash when the engine is hot.......less lift. Lash should be set with engine hot!!

Lem Evans wrote:The Pac 1243 is a very good spring. I use and sell a lot of them. Same spring Ford uses in the M-6049-SCJB cylinder package.

Great spring ... or, the Pac-1244 @ 1.900" installed height when you need to use a little more lift

Double check your retainers especially the "B" dimension on dual springs. The step for the inner spring, on springs with close to the same outside diameter can call for a different size. One example is a 1.570" spring calls for a different retainer than a 1.550" spring, made by the same company.