99gst_racer
Moderator
- 11,976
- 1,542
- Apr 5, 2003
-
Coloma,
Michigan
! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
EDIT: Fluidampr has made a running change on the hub thickness on these. See post# 31.
! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
The stock damper bolts are not long enough to use with the Fluidampr damper. I found this out the hard way by shearing 3 of them off while driving on the freeway 2 weeks ago, and I wanted to share this with everyone on this site so that you don't risk the same failure that I experienced.
I got off the highway after hearing something loudly eject from the engine bay (turned out to be the third bolt). We pulled into a parking lot and popped the hood to find the damper wobbling badly. Turned out that I sheared 3 of the 4 damper bolts and the last one was deformed and on it's way out. These were factory grade 8's, loctited and torqued to spec. After a lengthly discussion on the Link forums, we concluded that there just wasn't enough thread engagement and this caused them to work themselves loose enough to allow them to shear with high engine loads. I was extremely lucky the damper didn't come flying off at 8000 RPMs. I had been running this damper and these bolts for the past 3 years and they were doing fine until this incident.
The Fluidampr uses a thicker hub and that only allows for roughly 8mm of thread engagement with the factory bolts. 12-16mm of thread engagement is required. The fix is to use a longer bolt, of course. The factory bolts measure out to be M8x1.25 x 25mm. The Fluidampr requires at least 10mm longer bolts.
For mine, I ordered replacements from ARP. Their part number is 661-1004.
Specs are as follows: M8 x 1.25, UHL = 35mm, 8740 chrome moly, black oxide finish, hex head.
Using these ARP's, I should be able to achieve about 18mm of thread engagement (all but 2 threads), which should be plenty to keep these bolts tightened.
Feel free to comment or ask questions.
And here's a pic of my old sprocket next to the new one. Looks like it also chipped part of a tooth off when the third bolt went. And the centering ring is nonexistent. I remember half of it falling out when we pulled the damper off in the gas station parking lot.
EDIT: Fluidampr has made a running change on the hub thickness on these. See post# 31.
! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
The stock damper bolts are not long enough to use with the Fluidampr damper. I found this out the hard way by shearing 3 of them off while driving on the freeway 2 weeks ago, and I wanted to share this with everyone on this site so that you don't risk the same failure that I experienced.
You must be logged in to view this image or video.
I got off the highway after hearing something loudly eject from the engine bay (turned out to be the third bolt). We pulled into a parking lot and popped the hood to find the damper wobbling badly. Turned out that I sheared 3 of the 4 damper bolts and the last one was deformed and on it's way out. These were factory grade 8's, loctited and torqued to spec. After a lengthly discussion on the Link forums, we concluded that there just wasn't enough thread engagement and this caused them to work themselves loose enough to allow them to shear with high engine loads. I was extremely lucky the damper didn't come flying off at 8000 RPMs. I had been running this damper and these bolts for the past 3 years and they were doing fine until this incident.
The Fluidampr uses a thicker hub and that only allows for roughly 8mm of thread engagement with the factory bolts. 12-16mm of thread engagement is required. The fix is to use a longer bolt, of course. The factory bolts measure out to be M8x1.25 x 25mm. The Fluidampr requires at least 10mm longer bolts.
For mine, I ordered replacements from ARP. Their part number is 661-1004.
Specs are as follows: M8 x 1.25, UHL = 35mm, 8740 chrome moly, black oxide finish, hex head.
Using these ARP's, I should be able to achieve about 18mm of thread engagement (all but 2 threads), which should be plenty to keep these bolts tightened.
Feel free to comment or ask questions.
You must be logged in to view this image or video.
You must be logged in to view this image or video.
You must be logged in to view this image or video.
And here's a pic of my old sprocket next to the new one. Looks like it also chipped part of a tooth off when the third bolt went. And the centering ring is nonexistent. I remember half of it falling out when we pulled the damper off in the gas station parking lot.
You must be logged in to view this image or video.
Last edited: