Comp cams 987 or 978, I seen traxion using the 987's and he was going mid 11's. But is the spring rate on the 987's of 344lb/in enough?? I hear the rate should be closer to 400lb/in like in the 978's but who has room on heads for an 1.85 install height??

 

springs have to match your cam, or your cam makers specs. as for who makes a quality spring i'd go to lunati, comp, or crane. i'd stay away from k motion and gm. installed height shouldn't be a problem, there are any number of things you can do to bring it in spec.

 

Well I am not changing cams...guess Ill be running the hot cam this season...I am going to be saving funds for a solid roller setup next season. I am just afraid of the Trickflow springs that come with my head not holding up. I have these now:
Valve Springs, Option 2:
1.470" o.d. single with damper
120 lbs. @ 1.780" installed height
300 lbs. @ 1.280" open
360 lbs. per inch rate
.540" maximum valve lift

Wondering if I could just swap the springs out and use all of the original stuff? The install height on these are 1.78 and on the Comps its 1.80..not much difference. However I am going from a single to a double.....not sure if the Trickflow have the retainer for the double already installed??

 

I'm running Trickflow heads with thier 1.46 double springs and a LT4 Hot Cam without problems.


1.460" o.d. double with damper
125 lbs. @ 1.780" installed height
376 lbs. @ 1.180" open
420 lbs. per inch rate
.600" maximum valve lift

 

I'm running Trickflow heads with thier 1.46 double springs and a CC306 Cam, 6800rpm, without problems.