72 duster resto

72smallairparticler said
Left spring - for my comp thumpr cam
Right spring - came on the heads - Bryan mentioned they're not enough spring rate for my cam

Im a little nervous using this cam now. Bought off a member here but I don't know how the shorter spring is supposed to hold a higher spring rate than the taller ones on the heads... I dont know, first time builder so just a gut reaction.

Option A - just go with it
Option B - pull the thumpr cam, keep the taller springs on and order Bryans matching performance cam from IMM engines that works with these springs. ($325) Sell the thumpr cam and springs?

diameter, wind and material all play a factor in spring rate.

if those springs are specifically matched to the cam, then i won't worry about the rate. i'd be more concerned about the install: are they the right diameter for the heads & keepers. will they be the correct installed height and allow for use of the locks. etc, etc, etc.

since you asked, and since i like spending other people's money and i don't particularly care for thumpr cams... i buy the matching IMM cam and sell the thumpr stuff along.