If you are looking for stronger valve springs for a challenge car, are there junkyard options?
If so how do you know what fits and what doesn't?
I think it was v6buicks that used ls6 (maybe) springs on his turbo 3.8 build.
is it as simple as measuring the size of the spring and finding a similar shape and then measuring how hard it is to compress?
this is all coming from a idea to build a 4.6 North Star challenge car (probably not a good idea, but oh well)
I can't seem to find the stronger springs for it.
I also am currently doing an ecotec build that the stronger springs from ZZP cost $300. Would like to find a junkyard alternative.
find some 'conical ' type valve springs' there are a few websites( look into valve springs website,, there are a few )find your engine,, open/close. seat pressures find a spring that you want to use,,, thats how i found my conical springs for my 2.2 ecotec, without spending lots of $$$$$$
Also remember that it's a Challenge car. part of the joy is valve float at the point of piston contact.
In reply to QuasiMofo (John Brown) Forum Supporter :
Your definition of joy is not my definition of joy.
I don't think valve springs can be the limiting factor in a GRM2k build unless your last name is Nelson.
I need to find some yellow or blue LS springs to use a bigger cam in mine...........I learned that from Andrew or Calvin.
A stock Ford 5.0 pushrod motor on an autocross course is very likely valvespring endangered. Those springs were subpar when new, at high mileage they are fail deadly.
I'm going to bump this, found some info that CHRFab, used to sell springs for the northstar 4.6. That would get the lump out to about 8,000-8,500 RPM.
It seems like CHRFab went out of business at some point. I found some guessing in an online forum that they may have been factory springs for another vehicle
Now that I have a soon to be delivered northstar 4.6 car, I would like to try to find springs for it so I can run the RPMs up.
Any one have any thoughts or suggestions as where to start looking for the springs?
I've used springs from one application in another when I needed more spring.
It's really just a matter of knowing your dimensions and rate then finding the same info for other applications. A lot of it is available online. It just takes a bit of skill or patience when searching.
I've also come across aftermarket suppliers that sell upgraded/uprated springs for applications that don't need them. They're usually really expensive and provide little to no performance value. Typically people on a forum will buy a set, report big results, then everybody thinks they need them and they become must have parts in a build.
Want a set of "performance" springs for your Geo Metro powered build? Chevy Aveo 1.6 springs. Better material, same dimensions, and a 10-15% increase in rate. I found those ones just by searching by dimension. The reality is we've run the stock springs at 20psi and 9000 RPM without issue.
In reply to Mr. Peabody :
Dont forget to measure the free height. I have dozens of valve springs for my Jaguars the way I decide to keep them or toss them is I line up about 10 known good springs and leave an opening to slide a spring in the middle and compare heights
shorter? They get tossed.
im lucky the stock springs are ok to 8300 rpm
In reply to Mr. Peabody :
Thanks
this is what I have found reguarding the stock springs
Is the spring rate just the number of pounds it takes to compress the spring fully?
In reply to frenchyd :
You should just do it properly by measuring and discarding any that are below the free height spec
In reply to Somebeach (Forum Supporter) :
It's best to know the installed rate.
You can set the spring to the installed height spec and measure the force, then compress them to max lift and measure the force.
In reply to Mr. Peabody :
My way is faster. Just as precise. In effect I am measuring them. But instead of using my veneer calipers I use a straight edge.
Springs to the left, springs to the right, Straight edge on top.
Now slide an unknown spring in between the stack on the left and the stack on the right. If the spring touches the straight edge it's the same height as the known good springs. iIf there is clearance it gets tossed.
When you check at least 24 springs at a time. Time savings become important.
Somebeach (Forum Supporter) said:
Is the spring rate just the number of pounds it takes to compress the spring fully?
No, the spring rate is usually given in pounds/inch which is, as the name implies the number of pounds it takes to compress the spring an inch. Generally speaking you should never compress a coil spring to full coil bind. That can actually damage the spring. When testing springs if you can't get a full inch of compression without coil bind you should compress it a smaller amount and *gasp* do some math.
If you're just comparing springs the rate is a useful metric. If you're selecting a spring for a specific application (and you have a lot of choices) then you should consider seat (valve closed) pressure and pressure over the nose (valve opened). Those numbers usually come from the cam and/or valvetrain manufacturer.
In reply to APEowner :
Thanks, I can tell I have some more learning to do.
I found the specs of the springs CHRFab used to sell.
It gives another piece of the puzzle I guess
From the above hot rod article
"According to Northstar specialist Cadillac Hot Rod Fabricators (CHRF), the only differences are the intake cams and valvesprings. The LD8 intake and exhaust cams have the same lift and duration: 0.339/0.339-inch valve lift, 244/244 degrees duration at 0.1mm (about 0.004 inch) lift, 22 degrees of overlap, and a 112-degree LSA (lobe-separation angle). The L37 intake cams have 0.0370-inch lift and 266 degrees duration. "
Can I use the .339 inch valve lift and the numbers from above to figure out the spring rating?
Am I reading it correctly to say that the weight increased 80# over the factory lift of .339 inches?
and 80/.339 is 235#/inch?
Somebeach (Forum Supporter) said:
In reply to APEowner :
Thanks, I can tell I have some more learning to do.
I found the specs of the springs CHRFab used to sell.
It gives another piece of the puzzle I guess
FYI, pretty sure that's FWD northstar stuff. Not saying they won't work on an 05+, but I wouldn't assume it without verification.
Somebeach (Forum Supporter) said:
From the above hot rod article
"According to Northstar specialist Cadillac Hot Rod Fabricators (CHRF), the only differences are the intake cams and valvesprings. The LD8 intake and exhaust cams have the same lift and duration: 0.339/0.339-inch valve lift, 244/244 degrees duration at 0.1mm (about 0.004 inch) lift, 22 degrees of overlap, and a 112-degree LSA (lobe-separation angle). The L37 intake cams have 0.0370-inch lift and 266 degrees duration. "
Can I use the .339 inch valve lift and the numbers from above to figure out the spring rating?
Am I reading it correctly to say that the weight increased 80# over the factory lift of .339 inches?
and 80/.339 is 235#/inch?
These are also FWD stats. LD8 and L37 were the two flavors of FWD Northstars (STS VS SLS).
You need to look at LH2 info. One of the changes when the N* went RWD was the addition of VVT, so I doubt they share cam specs with the earlier engines.
In reply to Dead_Sled :
Rats. Good catch I didn't think about that. Just assumed the spring would be similar.
Out of curiosity, is there a site that lists valve spring specs for various vehicle engines? Car and or motorcycle
In reply to Alfaromeoguy :
Wondering if you would share what springs you used with the 2.2 ecotec. Did you have to change spring retainers?
