bhaas

I just bought these heads and had K-Motion K-700 springs put in. I barely maybe have 1000 miles on these. I had a miss, and to make a long story short I had to take off a valve cover and noticed Cyl #3 had a spring broke and it was in 3 pieces Anyone have any probs with these springs? I had some L98 springs laying around so I put one of those in. No prob. Then proceded to go to the track. What a nightmare that place was. Only got 2 runs in and on my second run I ran a 13.769 and they told me I needed a helmet. Good thing I was leaving anyways, cause I would have ended up waiting an hour or more to get in another run. I tell you.

Brad...

Justins86bird

I believe Willie broke several Kmotion springs in his supercharged Camaro.

bhaas

Which K-motion springs were they? Were they the 700's ?

Brad...

Justins86bird

I'm not sure which p/n they were. Here's the link to his post.
https://www.thirdgen.org/oldarchives...sages/2004.htm
In the reply to my comment, he only says that they were kmotions with 1000 miles on them.

bhaas

I guess I'll be changing my springs. That's If I would have sucked a valve my motor would have been done for. Thanks.

Brad...

Guest

Another K-motion bites the dust... why am I not surprised?

BadSS

We use to sell K-motion at my old speed shop, but quit selling the entire line after a number of set came back broken (most were the 700s)- no help from K-motion either.

To add to that, I had an old set of TFS heads I bought back in 94. I might have put 500 miles on the heads doing a little R&D with them on an engine combination. I stored the heads until 2000 with the springs off the heads in the box until I sold them. The dude put about 300 miles on the heads and came back to be screamming about 3 springs breaking.

I called TFS just for $hits and grins to see if they had had a problem with the springs on the older heads. Arty from TFS (just so happens the guy I bought them from in 94) asked about the stripe on the spring and said "yep - those are K-motions (700s)". He said a very large percentage of heads they sold back then with the 700s came back with at least one spring broken. He also said that even though there was an obvious problem them,, as in my case with the speed shop K-motion refused to "warrent" the springs. Needless to say they no longer use the K-motions on TFS heads anymore.

Anyway,,, long story short - The 700's had a problem in 94 and they still do now. I hate it for you,, but you need to replace them all --- at least I would. I'd recommend Comp Cam springs - I've never had any problems from the many engines I've built using Comp products.

F-BIRD'88

I've also busted a few of these springs now.
I thought it was just a fluke because I had a problem with the trans not shifting from 2-3 at the drags causing me to overrev
the car a few times. But now I've changed 3 and I think
another may have broke tonight.

Going to change them all out to some Speed pro Z28
style springs and throw all the spare K-700's some one gave me
in the trash.

RSFreak

I was on hand to witness Brad's spring replacement. Yep, it was broken alright! Sorry SIR was such a bitch. Glad I didn't go now!

-John

screaminformula

yea im pretty glad i didn't show up either. with the way my Formie is runnin id have probably blown a hole in her piston!!!!

ede

i wouldn't use k motion springs if they were free. i run lunati springs in all the heads i do.

RB83L69

What ede said... I would include GM along with K-motion BTW (think of the HOT cam kit)

I use Lunati, Comp or Ultradyne, properly chosen for the cam profile of course; I prefer to use the next "bigger" spring than the minimum one for the cam I'm running.

good thing that spring didn't let go at 6000 RPM. Have you ever seen an engine that got lunched that way? You'll never again cheap out on valve springs once you've seen that.

Lounge Lizard 6

My '95 vintage TF G1s busted 4 POS Kmotions before TF admitted there was a problem with them.

Vader

Hey, Max! You KNEW I was going to pipe in on this, didn't you?

I had an "experience" with the K-Martion valve springs, and if you search the archives for "broken" and "spring" and "K-Motion" you'll likely find more than just a few threads.

I'm not saying they're bad or anything, but just do a survey and see what YOU come up with...

Blackened

Hey the springs on my TFS heads had a green stripe on them when I first bought them a year ago !! Do you guys think these are K-Motion springs ?! I'm already pushing them with my .524 lift cam. TFS says they're rated at .520 max !

Vader

Dammit, Ede! Quit beating around the bush and tell us how your really feel, will ya?

I was going to suggest Comp, Crane, or Lunati. But just as soon as you suggest something, someone will have a bad experience with it, then you're the bad guy for recommending it. Stick with the reputable old guard brands and you should have good results.

NTChrist

I've already bought a set of K-motion 700's for my set of 416's.
These heads will be running with a '93 LT1 cam, with possibly 1.6 rockers. In other words, I'm going to be running about 0.480" lift.
Am I guaranteeing myself a spring failure?
What lift/cam were you running, bhaas?

bhaas

I'm running the CompCams XE268H and it has a 480 lift. When I was asking questions as to what to do to my vortec heads someone suggested I use the K-700's so I did. Now I get to buy new springs and get to replace them all. Oh boy I can't wait to do that. Replacing them on the motor is so much fun. NOT!!! At least I have an air compressor and the tools to do it. But I can think of a much better way to kill a day. If I were you and you haven't use those POS springs, I'd send them back imediately.

Brad...

ede

the only real advantage i can see k motion having is the price is less than most all other makes and i believe that's what sucks everyone into running them. no one ever talks about valve springs, no exciting like a cam or a carb, but they one of the more important parts in an engine.

NTChrist

Thanks lots for the heads up. The parts are going together soon, this thread was just in time.

F-BIRD'88

Sell them, or give them to some one else. Yes you will see failures.
I have .465" lift and they lasted a yr. Now three broke in 3wks.
You'd be better off reusing your stock springs if you're on a tight budget till you can get some other brand.

RSFreak

Its much easier once you figure out how the spring compressor works, huh Brad?!

(Just kidding!!!)

screaminformula

LOL!! id rather do it by hand, those damn spring compressors are complicated!! (just kiddin!!!)

NTChrist

I called Summit, and they have agreed to take them back, with a 10% restocking fee.
The tech I talked to recommended the Comp Cams springs that will fit in the stock spring pocket.
For $70, I figure it's not that bad of a loss.
Thanks for the heads up!

bhaas

You two are pretty funny. But I wouldn't quit my day job if I were you guys. LOL

Brad...

Vader

The Rob Zombie version of " Who's your Daddy" ??

DM91RS

LOL I needed that!!!!!!! HAHAHAHAHAHA