I have an act stage 1 clutch and a 14lb exedy flywheel on an 03 wrx, the clutch/flywheel are relatively new (about 1500 miles on them, 500 freeway, the rest street). For the first time the other night, I decided to launch. I was planning on launching by pumping the throttle around 5-6 rpm, letting the clutch out till it began to catch, hesitating on the engage, and then fully engaging the clutch. Well, what happened was that when I let the clutch out to initially jolt the car forward, there was a loud bam/crack/thump from underneath the car that I felt into the gear shifter. I'm wondering what this was caused from. What I figure is that because my clutch is going to grab harder, and at the engine load associated with the rpm that I was at, it was just too much for the transmission. The car feels the same when it drives, but I'm thinking that I may have damaged a tooth or even maybe a tranny mount. It kind of sounded like my transmission jolted or moved.

My questions are:

Do you all agree that what I said is probably what happened (as far as the cause of the noise and what happened)?

If I did damage a tranny mount, I would assume that I should replace it. Can I use an sti tranny mount? What is the difference between this and the oem wrx tranny mount? From what I can see, it just appears that it's a solid piece of metal as opposed to one with a big hole in the middle.

This question is perhaps not meant for this forum, but it fits the post. Do I need to change my launch style? i.e. maybe pump the rpms at a lower rpm, is there a better way to launch, or is there no way out of it and I probably shouldn't launch till I do some tranny work (gears/etc/etc)?


Thanks for the input...