Do you know if all Redlines had the torque arm John?
Cuz mine clunked like a sonofabitch! Everytime I put it in 1st gear!
I need to know what to look for too to see what the difference is. It's at my mechanic's as well so it will be them that have to look for it, and tell me.
Like Robo, I have never heard of a RL without a torque arm. The difference is a big beam parallel to the propeller shaft that connects the drive axle to the transmission instead of having the nose of the drive axle bolted to the chassis.
Expanding on Robo's answer, the clunk (at least in my '07 NA) occurs when the driveline unloads and then loads again during a shift from 2nd to 3rd. I have not heard it any other time, and my RL doesn't do it at all.
That's what we were told at the time and I didn't question it much.
What I do know is that when I shift, the back end wiggles just a bit then gets back in line. Happens if you shift in a turn and not nearly as noticeable (if at all) if you shift while going in a straight line. Did this as a 2.4 NA...does it now. I have the early style without the torque arm.
I have driven a Redline and no such wiggle at a shift point with traction control completely off (specifically to eliminate traction control being a factor since my 2.4 doesn't have it at all).
I never had a clunk nor do I have a clunk now. Never had a clunk in my first NA 2007 early build car either (also no torque arm).
I never delve deeper into it as I had no plans on changing it...for autocross you only shift into second once and rarely ever change out of that gear from there so no big deal. I always thought it had something to do with the torque of the driveshaft deflecting the diff case just enough to cause an axle or axles to bind momentarily when going from 1st to 2nd under hard acceleration while turning. Since it only happened while turning and accelerating hard, figured it was just enough to break traction for a split second and make the back wiggle then recover when the diff case returned to it's normal position.
I don't know enough about this to contradict you, I just can't quite grasp the mechanics of it. I assume that the RL didn't have a ProBeam? My NA with a ProBeam was more stable that the RL before I added one to it, and both had what i would describe as a wriggle before I installed it, although it also showed up when transitioning in and out of turns.
Just as an aside, I think that the Probeam is the single most important modification you can make to one of these cars.
I doubt that clunk is the Torque Arm. If you're putting it into first, chances are you are stopped. Driveshaft isn't turning thus it's not going to put any force on the differential.
The torque arm should be on every Redline. (Did a Google search since I wasn't positive before.) It was introduced to the NA cars before the Redlines were released. This is one more difference between the early build 2007 NA Skys and later build 2007 NA Skys.
I agree with this.