Just wondering. I know they should be changed to be safe, but I don't wanna do it. I feel ok not changing them, just wanted some opinions.
Rocketman said:According to the SHM 4.6 book, you are safe with stock springs ( PI head ) up to .550 of gross lift. So, as long as your cam specs don't exceed that amount of lift, you will be OK.
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Purebred said:Where can I get that book??
Rocketman said:
mdvaldosta said:Thats my philosophy as well. Its not the cost of the springs, its the fact that its gonna take all friggen day to change the springs when its gonna take just a couple hours doing the cams.
Also, Bill Putnam was said to have gotten 22 rwhp from stage 1's and he changed the springs, and another guy showed 33 rwhp and he didn't change them. Now it could be alot of other factors like mileage on Bill's car etc., but I think that putting stiffer springs would rob some hp.
I KNOW I will be safe spinning to 6k, but looking at the powerband of the cams it appears it would be best to shift at between 6300 - 6500 rpm. Kinda scary on stock springs, thats my biggest concern.
I've looked on Modular Depot for a thread relating to this by the way, but to no avail.
mdvaldosta said:I am a knowledgable hand. I expected if Bill posted he would "recommend" a spring change. I really wanted to hear from people with experience running the stock springs - or knew people that did. In particular Im wondering about possible valve floating over 6k.