has anyone noticed in the valvespring section of the comp catalog the recommended springs always seem to fall short on max lift compared to the lift of the cam they are matched to? i'm probably confused here. :confused:

bt,
I think there are more mistakes in that chart than there is correct info. To make it worse, we have one of thier wall charts and it has different mistakes :( I have given up on the chart and go by past experience, check an actual spring, or call them and ask to make certain.

Originally posted by bowtie455:
has anyone noticed in the valvespring section of the comp catalog the recommended springs always seem to fall short on max lift compared to the lift of the cam they are matched to? i'm probably confused here. :confused: Bowtie, You are not confused, You are correct, I have brought this up a number of times over the last year. There are a few discussions you can find with the search function.


http://www.chevelles.com/cgi-bin/forum/ultimatebb.cgi?ubb=get_topic;f=4;t=014087

Here is the link for a valve spring worksheet

http://www.chevelles.com/cgi-bin/forum/ultimatebb.cgi?ubb=get_topic;f=4;t=019163

thanks much,guys! graemlins/thumbsup.gif

Wait till you start checking installed ht.
Had a comp 982 spring kit. Spec'd at 1.700 installed, got 1.800 on brand new gm heads that measured 1.700 with the stock parts.

Oh, and comp tech said to go a head and run them at 1.76 or so for an XE274. 060 shorter 10* retainers are about $60 btw. Tried a different spring/ret combo. The 983's, that they said would fit stock vortec heads. Not! Got guides cut down.
Installed ht didn't match either. I know one engine builder who won't run comp springs anymore for just this sort of quality issue.
I ended up using Isky springs/ret. that came out dead on at the spec.

The spring recomendations are confusing also, My Son's XS268S calls for three differnt spring part numbers depending on what info you're looking at. I realize the stiffer springs are for a more serious application but there are no printed guidelines whatsoever. Oh well, hope I talk to the right person on the techline.

I am in the middle of this problem also. I found the cam I wan't which is the biggest cam for the 981-16 springs that I wan't(dont require head machining). So I get the cam and springs, and then I read in the back of the Comp book that these springs are only good to .450" lift! It specifically says to use the 981-16 springs with a cam that has .490" lift! wtf Im gonna stick it on and see if I have the actual .060" to coil bind or what's goin on.

looks like choosing the right springs is as much a "black art"as choosing the perfect cam.years ago we just picked a cam that had a "mean lope" and stabbed it in and crossed our fingers.it seems like the more advanced technology gets the more complicated things get. ;)