I'm still screwed up about this spring thing as there is a lot of conflict that I just can't explain in less than 5 pages of crap.....

So, can anyone explain what this means:

Dart Pro 1 ,345cc
Spring Cups: 1.625” - .035 cup / 1.550” - ID locator
Spring Pockets: 1.740” OD for 1.625” cup (.030” deeper max)
Springs: Our Assembly: 1.550S = 145# @1.900” / .660” max Comp 936
1.550D = 195# @ 1.900” / .690” max Comp 954
1.625D = 250# @ 2.000” / .790” max Vasco-Jet H-11

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The closest cam I could get to mine is 11-691-9:
Camshaft Specification Table
Part Number 11-691-9
Engine 1965-1996 Chevrolet
396ci-454ci
8cyl.
Grind Number CB 280A-R10
Description

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Intake Exhaust
Valve Adjustment 0.02 0.02
Gross Valve Lift 0.622 0.622
Duration At 0.015 Tappet Lift 280 288

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Valve Timing At 0.015
Open Close
Intake 34 66
Exhaust 78 30

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These Specs Are For The Cam Installed At 106 Intake CL
Intake Exhaust
Duration At 0.05 238 246
Lobe Lift 0.3666 0.3666
Lobe Separation 110

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Recommended Valve Springs 929-16

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Here is the valve spring chart (would not let me copy and paste),
so you have to scroll down to 'dual valve spring assemblies' and
look at Part#929

http://www.compcams.com/Technical/Cu...ML/337-338.asp


Somehow that 929 spring just does not seem right

 

From what I see your springs can handle the lift of your cam now.Max .660 and your cam .622, No need to go any stiffer than needed.

 

That 936 that you are looking it is a single spring.....
Not sure I trust that spring, that's why I'm looking for a double.

...I've dropped a valve before!....on a set of aluminum heads

 

I would go with crane springs #270-96882-16 in the jegs catalog. Double spring up to .650 with 1.540 cup.I prefer crane over comp,had many parts failures with them.

 

Thanks!!
Will do!

 

I am now using a similar series set on a crate LS7 454. If you are using an unassembled set of heads, I would recommend calling Dart. These have 119 cc chambers that are open and when used on 66-69 engines with stock pistons will lower the compression ratio. In addition stock length pushrods and head bolts will not work properly because of the taller deck. You will need at least .200+ over stock for the correct rocker arm geometry otherwise you may be riding on the edge of the retainer. I forgot the exact length I used however. At least go to their web site and look them up before attempting to install the heads.

 

double's

 

I've had the heads for a while!!
Had the Dart Pro 1's on my LS7 last year and now on my new toy since early '04
I was fooling around recently and had the valve covers off to check
my rollers when I found two broken springs.

Therefore the mad search for new springs and in the process just asking
questions that popped up in my mind. You know what happens when you break stuff and deside to buy new stuff....

....you figure you should upgrade to bigger and better and then your brain goes all gagga.

It's easy to give others sound advice, but somehow one's brain goes funny when it's about yourself and simple logic goes out the window.