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> Valve Springs, From double to single valve springs
CG-914
post Aug 14 2012, 03:00 PM
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I got my heads converted from single to double valve springs.

Now I am putting the 9550 Cam setup in my engine and was wondering if I can just convert them over to the HD Valve Springs that come with the Kit or not?

Len Hoffman said I should use "Crowler Springs" I never heard of them and was wondering if anybody can tell me something about them?

Or are there any other solutions?

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CG-914
post Aug 16 2012, 12:08 PM
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I meant Crower Springs (IMG:style_emoticons/default/lol-2.gif)
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Randal
post Aug 16 2012, 12:21 PM
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QUOTE(CG-914 @ Aug 16 2012, 11:08 AM) *

I meant Crower Springs (IMG:style_emoticons/default/lol-2.gif)



I would strongly recommend you accept Len Hoffman's suggestion. He's a total PRO and knows which springs work with which cams.

If the springs aren't specified to work with the lift of your cam/ RPM you motor is designed to turn/ lifters and rockers, you will likely experience valve float. Not a good thing.

In fact check the entire design of your heads with Len before you put them on the motor.

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BarberDave
post Aug 16 2012, 01:00 PM
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(IMG:style_emoticons/default/smilie_pokal.gif)

You, NEVER EVER, don't do what Len Hoffman ,tells you to do with Type 4 Heads!!

NEVER EVER !!! " As it is said so shall It be Written' !!!! Dave (IMG:style_emoticons/default/slap.gif)
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SLITS
post Aug 16 2012, 01:02 PM
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www.crower.com

Been around since dirt.
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cgnj
post Aug 16 2012, 01:59 PM
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Well, I expect that Jake sent you the correct springs if you purchased the super kit. Isn't that his point of his cam program?

Based on a post that Jake made regarding 9550 cam, you run out of cam at around 6200. I find it hard to believe that you could float the valves unless unless you missed 3rd on a downshift and caught 1st.

If you indeed purchased the super kit add-on, I would swap them out. Otherwise, I would run them. I don't think the the manufacturing process for lifters or cams changes based on the grind.


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SLITS
post Aug 16 2012, 02:57 PM
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Not knowing what springs that were recommended, we used Chevy dual springs on the race car.

We also had a spring tester so we could determine the length of the installed spring for the seat pressure and over the nose pressure we wanted (valve train control).

Further, we would polish the ends of the spring and run washers underneath to avoid the sharp edges of the spring cutting into the head.

Lastly, I hope you have the figures for installed height and avoidance of coil bind on compression of the spring.

A lot more to it than just running "dual springs".
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HAM Inc
post Aug 16 2012, 06:23 PM
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I already went over this with Cornelius (twice), but I'll share it with everyone else so you'll understand why I recommended switching to the crower springs and not using the single springs that come with Jake's kit. The single springs that Jake sells are fine springs.

The heads have already been cut for dual springs. The type of dual springs that he's been using are interference springs that locate in the heads off the inner spring. And the outer springs have the same dimensions as Jake's single springs.

If the inner spring is eliminated the outer will have no boss to align it and it will float around.

The crower springs that I recommended have a larger O.D. and will locate in the head firmly and allow no shuffling.
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CG-914
post Aug 18 2012, 07:36 AM
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QUOTE(HAM Inc @ Aug 16 2012, 08:23 PM) *

I already went over this with Cornelius (twice), but I'll share it with everyone else so you'll understand why I recommended switching to the crower springs and not using the single springs that come with Jake's kit. The single springs that Jake sells are fine springs.

The heads have already been cut for dual springs. The type of dual springs that he's been using are interference springs that locate in the heads off the inner spring. And the outer springs have the same dimensions as Jake's single springs.

If the inner spring is eliminated the outer will have no boss to align it and it will float around.

The crower springs that I recommended have a larger O.D. and will locate in the head firmly and allow no shuffling.


Hi Len, I do believe that what you recommend is the best with the incredible reputation you have! That is also what I want, but I have to at least look for plan B because spending $1300 for a 23 year old student is somewhat impossible (IMG:style_emoticons/default/dry.gif)

Thank you for all your help so far though!!! (IMG:style_emoticons/default/pray.gif)
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Mark Henry
post Aug 18 2012, 10:50 AM
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QUOTE(HAM Inc @ Aug 16 2012, 08:23 PM) *


The heads have already been cut for dual springs. The type of dual springs that he's been using are interference springs that locate in the heads off the inner spring. And the outer springs have the same dimensions as Jake's single springs.

If the inner spring is eliminated the outer will have no boss to align it and it will float around.


(IMG:style_emoticons/default/agree.gif) once you cut for dual springs you can't go back.

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