New to GTO, need advice on drivetrain mods to support power.
 

if you will drag race it, you're going to need to get new outer and inner stubs, new axles, a better driveshaft, and a good clutch. if you have an lt1-s, you should be good. GForce1320 or DriveShaftShop has plenty of goodies for the other stuff.

stock pumpkin is OK unless there is already some issue with it. they are stronger than people make them out to be. The T56 is usually pretty strong. if all you have done is heads/cam/intake to a 6.0, you are usually making less then 500whp so, not a ton of worries there. Probably 450whp-475whp.

a little suspension work would help with putting the power to the ground.

Axle splines will twist since you have an upgraded clutch. Nobody has trusted the two piece DS to big power, so no idea how far it will go. Everyone upgrades prematurely. The diff will hold, but the LSD will die quickly. When I upgraded Kaaz was the only option, but now there are others. The t56 is rated to 450ftlbs of torque, but is much stronger than the rating. Your front radius rod bushings and brakes are the two biggest concerns other than axles.

You should be making over 600hp easy with that setup. The stock t56 should be fine with the clutch you have and like others have said a 1 piece drive shaft and axles will go a long way with helping the rear live. The biggest thing to keeping the rear end alive on these cars is getting rid of the wheel hop.

Drag bags will definitely help.

Interesting that on these cars the 1 piece is considered an upgrade..
It robs horsepower.. Sometimes a lot especially over 70 or 80 MPH..
Seems like the real problem is the two piece from the factory needs fully
upgraded, all carriers, Joints, sliders etc.. Yea its a 800 dollar + adventure..

T56 is very strong as far as direct power handling, what it does not like is banging gears,
the synchro's just don't handle it well.. (More of a design issue..)
I've driven several dog box conversions and they don't care.. side step it off the line it just slams home and goes..

how does a 1 peice lose power?

It does not. The only real problem is the length of the one piece. The critical speed at which you experience potentially catastrophic vibration issues is lower with longer shafts. If you wish to go over 160mph or so with your car you will have to get a really high dollar one piece to insure you do not turn it past the rpm at which this becomes an issue. With the shorter sections of a two piece shaft this only becomes an issue at extreme speed levels. I have no idea WTF the previous poster was talking about with the loss of HP comment.

Carbon fiber driveshafts have more benefits than just a higher critical speed. They are lighter and safer. It's worth the extra cash, imho.

i wouldn't run a CF shaft in a daily, though. I wouldn't run an aluminum shaft, period. Two peices are just fine, even though good ones are expensive.

There are plenty and I mean plenty of GTO's running 1 piece aluminum driveshafts with little to no issue what so ever. The biggest issue ever reported with the aluminum 1 piece came from the early designs and the junk adapter plates. I have an aluminum DS from DSS and I have put it through some abuse with no problems at all. Two piece DS are nice but i feel you could better use the money saved on other things like axles.

It's just personal preference, man. As long as the u-joint angles are good a well build 1-pc should work fine.

I would rather spend the $$$ on something a little better, though.

To elaborate on your comment about CF driveshafts, they are strong as hell and have the highest critical speed available. The problem is that a few rock dings from daily driving can unravel them, while those same rock dings would do nothing to a steel shaft, or put a scratch in an aluminum one. If I had an underbody pan covering the DS, I would not think twice about using a CF for a DD, but otherwise, I would worry.

yeah, i agree. like i said, i wouldn't daily a car with a CF shaft. But, i do drive my car on the streets and tear it up, no issues yet. I went through plenty of trouble to clearance the exhaust as well as wrapping it so the DS wouldn't get too hot. Still, DSS makes a very good CF shaft.