Thread: Valve Spring Question
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06-28-2005 07:14 PM #1
Valve Spring Question
Ok here we go again.
496 BBC
Comp Retro-Roller 294 540/560 110
Angus 1.7 roller rockers
Ferrea 2.250/1.94 valves
Pro-Topline 320 racing thunder heads.
Comp 943 valve springs....
So the motor pulls very hard till about 3800 rpm, then after that it feels like my valves are floating. The only thing i can think of is that these valve springs are WAY to light.....specs below:
O.D./I.D. = 1.55o/.812
Seat Press. = 240/1.900
Open Press = 598/1.2500
Coil Bind = 1.160
Spring Rate =551
Now to me, looking over these numbers.....it seems light.
I have talked to a few of my motor buddies, and they all say to get new triple springs, because the ones that i currently have are double. I have also ran the lash several times.... 0 lash then a 1/4 turn more. But i still have small backfires theough the carb, which i would say is because the intake valve is staying open because of the light springs? Timing is 38 total and the carb is right on the money.
lay it on me fellas
You're welcome Mike, glad it worked out for you. Roger, it's taken a few years but my inventory of excess parts has shrunk a fair bit from 1 1/2 garage stalls to about an eight by eight space. ...
1968 Plymouth Valiant 1st Gen HEMI