How high of a lift can stock springs handle?
08-11-2008, 12:56 AM
#3
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RE: High high of a lift can stock springs handle?
ORIGINAL: jtmustang
not much more than stock .444 i wouldnt go any higher than like a b cam .480 and thats if u have a somewhat low mileage motor..?
not much more than stock .444 i wouldnt go any higher than like a b cam .480 and thats if u have a somewhat low mileage motor..?
08-11-2008, 01:08 AM
#5
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RE: High high of a lift can stock springs handle?
ORIGINAL: somedudeboy
If you are such an expert, then why did you feel compelled to ask?
If you are such an expert, then why did you feel compelled to ask?
08-11-2008, 01:12 AM
#6
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RE: High high of a lift can stock springs handle?
cause the stock ones were not meant for much more than stock and will cause valve float/bind at a much lower rpm = losing the full potential of the cam...
08-11-2008, 01:19 AM
#7
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RE: High high of a lift can stock springs handle?
stock springs are barely good enough for the stock cam... the ony reason the E cam worked with your stock springs... is because you didnt know any better than to change them.
I can assure you, if your car had been run on the dyno, you would have seen valve float up igh in the rpm's b/c the stock springs are meant for stock equipment
I can assure you, if your car had been run on the dyno, you would have seen valve float up igh in the rpm's b/c the stock springs are meant for stock equipment
08-11-2008, 01:27 AM
#9
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RE: High high of a lift can stock springs handle?
most good cams will tell you what spring set should be used with them.
however, IIRC there are only two spring kits that fit stock heads without machine work... and running a aftermarket cam WITH stock heads, is a HUGE waste
however, IIRC there are only two spring kits that fit stock heads without machine work... and running a aftermarket cam WITH stock heads, is a HUGE waste
08-12-2008, 07:44 PM
#10
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For simplicity sake, let us just say the stock valve spring is installed at 1.800" exactly.
You then compress the spring until the spring rings connect each other and that number is 1.300".
That gives you .500" before coil bind occurs. You will want ATLEAST .060" of leeway before that coil bind contact, which makes it .440" of useable spring travel.
Then you get into open and closed spring pressures, weight, style, etc.
General rules, but they can be twisted:
Racier lobes = Higher spring pressures needed = More potential flex
Street lobes = Lower spring pressures needed = Less potential flex
Lighter valvetrain = Less spring pressures needed = Less potential flex
You then compress the spring until the spring rings connect each other and that number is 1.300".
That gives you .500" before coil bind occurs. You will want ATLEAST .060" of leeway before that coil bind contact, which makes it .440" of useable spring travel.
Then you get into open and closed spring pressures, weight, style, etc.
General rules, but they can be twisted:
Racier lobes = Higher spring pressures needed = More potential flex
Street lobes = Lower spring pressures needed = Less potential flex
Lighter valvetrain = Less spring pressures needed = Less potential flex