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Discussion Starter #1
Hey all,

I'm getting the engine build bug from jedd as I follow along with his B20 build and am trying to finalize the list of parts I still need for my upcoming B18 build.

The head I have is a B18 head with dual valve springs, and was setup for a "hotter" Isky cam on a race-type bottom end. I'm aiming for a more streetable motor, with a less intense cam and SU carbs.

The spring buckets were obviously enlarged to accomodate the dual springs, but I want to go back to single springs.

Question is: Would the outer springs on this setup be enough on their own? Or, would I be okay going with a non-Volvo spring with a wider diameter than stock but appropriate length and spring rate for my cam? If so, does anyone know the "typical" spring rate for a single spring C or D, or IPD "Street performance" cam setup?

Thanks all.
 

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I remember being able to use stock springs on a head that had previously had the seats enlarged for doubles. I don't remember exactly what it looked like. but the machinist I used back then had no trouble -- there was some sort of collar thingy that centered the smaller springs in the larger holes. If you go with the D or the Isky SP cam, you might just want to leave the doubles in place.
 

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I'll ask about those buckets, Phil. I thought that would be an option, but I wasn't sure if it would be a concern adding more parts to the valvetrain like that.

For the dual springs, I was under the impression that dual springs were not ideal in these motors for "milder" cams due to parasitic power loss and the rev-happy nature of the dual springs.
 

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I'll ask about those buckets, Phil. I thought that would be an option, but I wasn't sure if it would be a concern adding more parts to the valvetrain like that.

For the dual springs, I was under the impression that dual springs were not ideal in these motors for "milder" cams due to parasitic power loss and the rev-happy nature of the dual springs.
For every spring being collapsed there is one going the other way, so that is pretty much a draw. Cam wear on the other hand is more exaggerated.
 
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