slade69

Can anybody say what kind of valve springs would be good for a mild roller cam:


P/N 514245-10 (howards)
VALVE LIFT INT. ,5173
VALVE LIFT EXH. ,5120
INT OPEN 29,5
INT CLOSE 61,5
EXH OPEN 74,5
CAM LIFT INT. ,3233
EXH CLOSE 26,5
CAM LIFT EXH. ,3200
OVERLAP 56
L/C 110
INT PHASE 106
ADV OR RETARD 4
INT. DUR 271
EXH. DUR 281
EXH PHASE 114
INT. DUR @ .050 219
EXH. DUR @ .050 229
INT O @ .050 3,5
INT C @ .050 35,5
EXH O @ .050 48,5
EXH C @ .050 0,5
LASH .000"
OVERLAP @ .050 4


How much closed pressure?
How much open pressure?
Spring rate?


Edelbrock recommends 150lbs closed, 420lbs open, 400ish spring rate. Trovato in his book recommends the same. These mean duals.
Howard cams told me to use spring kit #98113-K12 beehive. They are really mild in pressures(115/332). Are beehives really that good, that they will work with so much less pressure?


http://howardscams.com/i-24078478-ho...ainer-kit.html

cutlassefi

It also depends on the lifter being used. They have limitations as well.
I use 140 on the seat and about 360-375 open, depending on the rpm expected and the lifter being used.

slade69

Hyd.roller lifters are from Comp. Rpm:s below 6000. Would these be an overkill?


http://www.jegs.com/i/COMP-Cams/249/977-16/10002/-1


What do you think about Howards recommendation?


http://howardscams.com/i-24078478-ho...ainer-kit.html

Run to Rund

Beehives are good to reduce spring flutter but a flat damper spring works with conventional springs. Without knowing the dynamics of the lift rate, and the rate of lift, it is impossible to recommend the best springs. In general, more spring is good to prevent valve train float, but as noted above, some lifters and soft cam material aren't tolerant of extreme pressures and high ramp rates.

cutlassefi

The bleed down rate of the lifter valving is the biggest factor regarding spring pressure. As far as cams go, they better not be soft, it's a roller. Look up SADI and you'll understand what I mean.

Teamrude

Cutlassefi

similar question. Have a Howard 514155-08 being made (wish I knew this forum sooner) 286 total, 233 @ .050, .550 lift. Going in "D" heads. What springs and lifters do you suggest along with pushrods? I know there are crappy Hyd roller lifters out there and want good ones. Any suggestions? I PM'd you yesterday. Terry aka Teamrude

BillK

Terry,
I have always tried to go with whatever spring pressures the camshaft manufacturer suggests. Once you know the pressures needed than you can find a spring that will work on your particular heads. You will most likely need retainers also. I am doing a set of Edelbrock heads for a 455 in the shop right now and he is also using a Howards cam. I e-mailed Eric at Howards and asked him what closed and open pressures they wanted and picked a spring accordingly.

And no matter what anybody tells you ...... you simply have to measure your particular heads first. Factory heads can vary as far as installed height etc. There is no way of knowing what has been done to them in the past.

Any decent name brand spring should be fine as far as quality goess.

cutlassefi

Your installed height is most likely around 1.700 or so so it’ll be a little more difficult to find a spring with that short installed height, have the right pressure, and still take the .550ish lift.
I’ll see what I can find for you.