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"SI Valves" Valve springs? (PN: VS 1118)

S

Schwuppes

New member
hey people,

In my never-ending quest to find a perfect valve spring to be used with VS cam or 1.95 YT roller rockers Ive come across these:

SI VALVES


According to this graph they actually have a lower spring rate than stock L67 springs :) but still have a higher seat pressure needed for the increased lift. Looks like the SI VS 1118 the perfect spring for our L67 cam applications

springrate.jpg

Anyone got any experiences with this brand "SI Valves"?

Cheers
 


yeah according to that graph PBM 110's also have a milder spring rate than even stock L67 springs.... so how come everyone always recommends L76 springs? L76 springs have a fairly higher spring rate than the PBM 110's.

So out of all those shown in the graph the PBM's are the mildest on the timing chain and tensioner? Would that be a accurate statement?
 
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If that chart is correct, then yes.

I don't know why people recommend L76 springs...they aren't even rated at enough lift for a VS cam.
 


Ah yes, you guys have some cars with 1.66 rockers and some with 1.6 rockers over there right?

I'm pretty sure we don't have that situation here in Aus.
 
Stock rockers are not technically a fixed ratio. With the stock cam, they are rated 1.6 to 1.66, depending on who you ask. However, due to their design, the rocker ratio increases as cam lift increases. So with a VS, your ratio may be closer to 1.7.
 
yeah I was wrong anyway... stock rockers are rated as 1.65 over here.... interesting point about the dynamic ratio though
 


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