Possible valve train or trans issue?

[Inferno_Orange_]

First off my car is an SS with 58,000 miles and 30,000 of those have been cammed with a GPI SS1 vvt. When I was getting on the on ramp the other day in second or third there was a blender/stuttering like sound in the upper rpms and it felt like the power was pulled.

I checked the dipstick for any sparkles and there were none and as far as I can tell it still idles and drives fine as long as you don't get on it. I've pretty much always driven the car in manual mode using tap shift (I can drive a manual so I don't think if it's the trans its due to my shifting) but it seems to drive fine in full auto as well.

I managed to get a video on the on ramp of the sound, it starts at around 5700rpm in second gear and goes in and out till red-line. https://youtu.be/dJ3uwCEMt_4

The sound doesn't come across too well in the video so I tried my best to clean up the audio and make it more audible. https://youtu.be/Qahf8q2PrKc

This is the same audio from the other clip but it starts at the beginning of second gear and goes to third.

I've had trans issues in the past such as it getting stuck in second gear after idling for a while(one was at a stop light and the other a drive through) but there was about a year in between those two events and the last time it happened was around last October. I did take it to a transmission shop after the last time and the guy there drove it with it hooked up to a scanner but it didn't throw anymore codes. (the code it had was output shaft speed sensor) and it hasn't done anything like that since then so I just assumed it was a tuning issue.

I'd like to hear y'alls opinions on this.

[Inferno_Orange_]

Turned out to be a broke intake valve spring. Somehow drove around 500 miles with this thing in three pieces without the valve ever hitting the piston thanks to the inner spring. Very lucky that it didnt eat a piston. So for future reference if your car is making these sounds and acting the same get it checked out quickly. Might try changing the plugs first though like I did but if that's not the problem it could end up being catastrophic.

[sixty9fordkiller]

from my understanding, springs need to be changed every 15K-20K miles or so on a cammed street car thats daily driven or often driven. Did you ever change the springs after you got the cam setup installed?

[Inferno_Orange_]

I wasn't informed about that until they found the broke one but I definitely have my trip logger reset so it won't happen again.

[Rock-It Man]

If your springs are failing after a cam change, it's because the springs are not properly matched to the amount of lift.

[sixty9fordkiller]

Originally Posted by Rock-It Man

If your springs are failing after a cam change, it's because the springs are not properly matched to the amount of lift.

he said they've been on for 30K miles or so. wouldn't coil bind would cause catastrophic damage to the valvetrain at minimum right off the bat?

[Rock-It Man]

Originally Posted by sixty9fordkiller

he said they've been on for 30K miles or so. wouldn't coil bind would cause catastrophic damage to the valvetrain at minimum right off the bat?

It's not just about coil bind...spring stresses are or are not in the range of infinite life, depending on whether they are right for the job.

[Inferno_Orange_]

Everything was done by gpi and I trust their work. I just didn't realize it was recommended to check them every ~20,000 miles or so. They even said that they don't really ever have problems with the springs, I just got unlucky.

[sixty9fordkiller]

Originally Posted by Inferno_Orange_

Everything was done by gpi and I trust their work. I just didn't realize it was recommended to check them every ~20,000 miles or so. They even said that they don't really ever have problems with the springs, I just got unlucky.

well, i wouldnt say too "unlucky".....you didnt hurt the motor,right?


thats a win on its own considering what could've happened

[Inferno_Orange_]

Very lucky in that regard. Just unlucky that it broke to begin with.

[Rem0v3r]

Mines been doing this for 2 years, been hunting it forever.. omg lol

[acammer]

Got pretty lucky there. Yea, 30k cammed is a bit much for a set of springs. 15-25k is about the limit you want to do on valvesprings. Making sure you have good heat in the car before hitting them with any significant RPM is important as well.

[Inferno_Orange_]

I think what helped them last to 30,000 was the fact that I let it warm up till the temp gauge starts moving before I ever leave.
Changing the oil and filter today too,
when I put the spring pieces together it's missing this little chunk, hopefully it's in the filter.