Should I change valvesprings?

[beanhead]

Hi guys, this question kind of got buried on a different thread... in my 440 I'm using a comp XE 274 cam, .488/.491 lift, 230°/236° @ .050 with Edelbrock RPM heads. Their springs are rated at 140lbs seat, 317 open..and Comp's 911-16s are rated for 122 and 309lbs. Using the stock rocker setup. The springs on the Edelbrock are a little bit stiffer, should I switch over to the Comp springs or is it not enough of a difference to worry about? Thanks for any help!

 

[lewtot184]

the 911 is a stiffer spring than the edelbrock, although advertised numbers say differently. compare spring rates.

 

[Cranky]

Got to compare the rates at the same installed height for both. I don't remember what that is on the Eddy heads....

 

[beanhead]

Ok thanks..the rates work out to approx 381 (comps) vs. 361 on the Eds, using my cam specs

 

[IQ52]

Hi guys, this question kind of got buried on a different thread... in my 440 I'm using a comp XE 274 cam, .488/.491 lift, 230°/236° @ .050 with Edelbrock RPM heads. Their springs are rated at 140lbs seat, 317 open..and Comp's 911-16s are rated for 122 and 309lbs. Using the stock rocker setup. The springs on the Edelbrock are a little bit stiffer, should I switch over to the Comp springs or is it not enough of a difference to worry about? Thanks for any help!

To simply answer the question...........It is not enough difference to worry about.

 

[lewtot184]

i went back thru some notes i've made and a new set of edelbrocks had close to the same spring rate as a used set of 911's. the edelbrocks would lose a little after some use. the 911's have 4 coils vs 5 coils for the edelbrocks; although the edelbrocks have a slightly larger wire o.d. personally, i'd do the edelbrocks. i'm over 911's.

 

[beanhead]

Ok that's how I was leaning too... but now I feel much more comfortable thanks very much guys