transmission

Does anyone have a good estimate as to how much HP/torque the stock transmission on a 1998 GTP can handle?..i read alot about transmission upgrades, but nothing about when its a good time to start getting stronger parts...thanks

In my opinion, I would say that if you are going to go much more than 50 HP over the stock, which air filter and small mods like that included, that I wouldn't take the chance. So I would get better parts if you were going to modify much further.

what would you start replacing first? (whats the most likely things to break first)

I'm not exactly sure what to start with cause there is a lot that you could do. Personally, I would check out the strength of my gears and also my gear ratio. And maybe your crankshaft. Other than that, you might want to go to a performance shop and get their opinion. When you do go and talk with them, though, you should definitely have in mind what ways you are planning on adding HP and also how much you are looking to spend. Well, good luck.

THe differential is the weak point in the transmissions, trust me as I have replaced 2 of them. Next would be the input shaft, which I have replaced once. The chain and gears really arent a weak spot but you can upgrade to a single chain set w/ 3.29/3.69 gears. I've also destroyed the pump shaft when the input shaft snapped.

Where would you recommend buying parts to strengthen the transmission?

Ripn,
You know all the mods I have on my car. Never replaced any of the parts you have listed above. Been lucky?
http://img.photobucket.com/albums/v425/kustomkid54/1998PontiacGrandPrixGTP004.jpg

Kid,

Well maybe a combo of luck and not enough HP. Also I used to race the car alteast once a week at the local track.

Prix,

I would look at INTENSE's website and also ZZP. All my parts were purchased from CYA RACING but I dont think he's still in the market.

Tim