Why'd you run the 1218s instead of the 1518s?

 

Ive seen that happen several times when not installed right.

 

I have the $200 Lunati .660 springs..

 

I'm not trying to answer for the guy, but if we assume he measured installed height and coil bind, and they both came out exactly to what PAC advertises (1.800" and 1.140" respectively) and if he decided to keep an added .050" clearance to be safe, we can see that he has .010" to spare (1.800-1.140-.600-.050").

It's cutting it close, but if he already had the springs I can see why he's running them.

 

Good info here guys. Any comments on the spring base issue?

 

I believe it just depends on which style of valve seal you are using. Seal & shim as one piece, or the seperated style. I run Crane dual springs. With your plans, I recommend dual springs for your setup also.

 

The 317 heads use the same valves (minus the sodium filled ones) as the LS6, which I believe are 2.00 I and 1.55" E. So I would say any spring meant to fit the LS6 (243 casting) will fit your 317 heads. I've tried finding the spring pocket diameter on the 243s and I can't find it. Perhaps someone else can chime in, cause I'd like to know this as well considering I have them on my truck.

The LS1 (241 casting) heads have a 1.63" dia spring pocket however, I managed to find that one.

 

I see 0.505" and 0.565" offered for most springs, what is this referring to? The diameter of the valve stems being used?

 

Really? where are you seeing this listed, because I only see OD and ID listed for these springs and even ID are much bigger than either .505 and .565"
http://www.pacracing.com/Beehive_Spr...Set_of_16.html

http://www.pacracing.com/Street_Stri...Set_of_16.html

http://www.compperformancegroupstore...Category_Code=

It's possible those smaller diameters are the measurements of the top coil of the beehives?

 

For instance the pat golds, http://www.jegs.com/p/Patriot-Perfor...22045/10002/-1

There are 2 different sets for the different spring base sizes.