rebobby

Has anyone been unlucky enough to have their GM OEM replacement springs fail?

Cruncher

Hmmmmmmm...to me, from your picture, the springs look to be exactly the same height...I don't see any difference.

Cruncher

It's pretty pathetic how your OEM springs were packed. However, they're a nice color (like that really matters). I bought the PAC springs from a Chevy/Buick/GM dealer at a really great price w/fast shipping. As I said, each spring was in compartmetalized; no spring touched any other spring and the box was clean inside.

The PAC 1218 springs are made in the U.S.----where are the OEM springs made?

rebobby

The height looks the same, but the lenght of the wire used to make the coil is longer on the blue spring. I lined up the end of the wire on the bottom of both springs directly facing the camera. The end of the yellow spring wire on the top end is about the 5 o'clock position, while the end of the blue continues CCW to about 12 o'clock.

rebobby

I agree, I was not impressed to see the packaging. GM OEM says made in Mexico.

ZeeOSix

Not true. The PAC 1218 and PAC 1518 have the exact same spring rate and exact same open and closed force. The 1518 is just more reliable (and a little more expensive) because the surface of the spring is micro bead blasted and nitrited for added toughness and less possibility of stress risers.

Go to PAC's on-line catalog and compare the spring specs and you'll see they are exactly the same between 1218s and 1518s.

Z06FEVER

When installing the blue springs in replacement of the yellow, is there any shims or installed height installation required? For better terms, is it as simple as removing the old spring and putting the new one in its place with no measurements or shims on a stock ls6?

LSX_NUT

^^^

ZeeOSix

Should be a simple drop-in. No worry about shimming. When I installed the PAC 1518s, the installed height was within factory spec. I would expect the same from the blue GM springs.

Z06FEVER

Thanks ZeeOSix, I appreciate it

Cruncher

Description Weight (grams) LargeEndI.D. (inches) LargeEndO.D. (inches) InstallLoad (LB) InstallHeight (inches) OpenLoad (LB) OpenHeight (inches) CoilBindMax (inches) LiftMax (inches) FrequencyBase (CPM) List Price Add To Cart
Each:

- PAC-1518 - PAC Racing Springs
PAC-1518 High performance LS1 spring that features additional nitriding processing for increased durability for high lift applications up to 0.650 lift. This spring remains a drop in replacement for extremely demanding applications. 75 0.885 1.29 130 1.800 318 1.200 1.140 0.625 29277 $18.29

The above is from the PAC web site. As stated above, the 1518 springs do in fact have increased durability "for high lift applications"..."a drop in replacement for extremely demanding applicationss."

I wanted springs that were OEM replacements (but not an OEM product)...my most demanding application is I-95.

ZeeOSix

You said the PAC 1518 have more FORCE than the 1218 ... that is not true as I said in post #206 above. Yes the 1518s have more DURABILITY and more lift capability due to the surface micro-bead blasting and nitriding process. But the closed and open valve spring force is the same between the 1218 and 1518 springs. Look at the force specs and you'll see that is true.

Cruncher

Force/lift---same difference:

force
Definition
force
[ fawrss ]
NOUN
forc•es plural

natural strength: the power, strength, or energy that somebody or something possesses

physical power: physical power, effort, or violence used against somebody or something that resists

nonphysical power: power or strength that is intellectual or moral rather than physical

Let's not wordsmith/nitpick it to death...you bought the better spring---are ya happy now? However, for me, I bought the better spring.

skyavonee

mmm, No... sorry

You made an incorrect statement, which ZeeOSix rightly corrected so others wouldn't be misguided. No big deal. That would have been the end of it, if you hadn't continued to post lots of erroneous information.

Cruncher

I didn't make an incorrect statement & I really don't give a flip on whether he bought PAC 12 million or PAC 60 million springs. Anyone that wanted PAC springs could have very easily seen what the difference is from the description. Yet he has to "gloat" on how he bought the very best in the world. I'm finished with this bull.

ZeeOSix

You obviously don't know the mechanical aspects and dynamics of valve springs. Please don't spew incorrect technical information to confuse others looking for the right valve springs.

chriskaw7r

What about mileage of failures?

halp

Mileage varies among those who did report it. From what was reported it certainly plays a part.
Only 5 reported failure under 20,000 miles.
20 (including the 5) under 40,000 miles.
34 had over 40,000 miles.
28 had over 50,000 miles.

I changed out my springs at 13,000 miles. Better safe than sorry.
Cheap insurance

racebum

mine made it to 90k without failure. 8/01 build 2002 car

previous owner was elderly and just did freeway travel so the engine has had less stress than many 20k mile cars. 3% cylinder leakdown etc

the local cars i know that have broken springs were all driven hard at some point

may not have been when the spring broke but there was road racing / heavy drag racing done.

skyavonee

Your sample size isn't large enough to make such a statement! I won't believe your numbers until I know the distribution of mileage among forum members!