[Sephx1]

Well it is just never ending with this car, if you’ve seen my thread on my Copart build. Had a leaking crankshaft seal and replaced it with the LS3 seal today. When torquing the Innovators West pulley back on to the recommended 130 ft. Lbs, with the car in gear and the parking brake on, the engine would turn before hitting 130 lbs. rear tires did not move. Although it drives normal with no noticeable slipping, it should not do this.

Does anyone have a recommendation on a replacement clutch? I plan on using the car on the street and road course track says.

[cosmok]

I would personally wait for more symptoms than the pulley install.

[Sephx1]

Originally Posted by cosmok

I would personally wait for more symptoms than the pulley install.

As much as I would like to do that, if it’s slipping with 130 lbs of torque I can’t help but wonder how much over 700 horsepower is making it slip.

[L78toLT1]

Originally Posted by Sephx1

As much as I would like to do that, if it’s slipping with 130 lbs of torque I can’t help but wonder how much over 700 horsepower is making it slip.

I concur with Cosmok. 130 ftlbs at 0 rpm is not equivalent to 130ftlbs at 1000+ rpm. If you do replace the clutch though, go ahead and freshen up those heads and install a Katec or the latest gm oil pump. You're obviously not afraid of work and if you lose a motor to a dropped valve, you're looking at over 20k for a crate LT4. At your mileage, I can't imagine that there is anything wrong with your shortblock. Too many unknowns with that valvetrain though. The additional labor involved vs just doing the clutch is fairly minimal. Dropping the engine and trans out the bottom is less of a a PITA than wrestling the transmission out by itself. Once the motor is out, addressing the heads and pump is not a big deal. You can pull a rod or main cap or two while you're at it just to verify the integrity of the bottom end.

[Sephx1]

Originally Posted by L78toLT1

I concur with Cosmok. 130 ftlbs at 0 rpm is not equivalent to 130ftlbs at 1000+ rpm. If you do replace the clutch though, go ahead and freshen up those heads and install a Katec or the latest gm oil pump. You're obviously not afraid of work and if you lose a motor to a dropped valve, you're looking at over 20k for a crate LT4. At your mileage, I can't imagine that there is anything wrong with your shortblock. Too many unknowns with that valvetrain though. The additional labor involved vs just doing the clutch is fairly minimal. Dropping the engine and trans out the bottom is less of a a PITA than wrestling the transmission out by itself. Once the motor is out, addressing the heads and pump is not a big deal. You can pull a rod or main cap or two while you're at it just to verify the integrity of the bottom end.

Thank you. Sound advice maybe I’ll drop the engine and transmission now that I’ve finally logged some miles on it. Track season is almost over here anyway.

[Katech_Zach]

The factory LT4 and LT5 clutches are great, I would just get a new OEM clutch. They are good for nearly 900rwhp without any issues.

[Sephx1]

Originally Posted by Katech_Zach

The factory LT4 and LT5 clutches are great, I would just get a new OEM clutch. They are good for nearly 900rwhp without any issues.

Thanks- good to know and less $$ than McLoed.

[Drnick]

Question ;OEM clutches on ZL1, are they single disc
Or dual disc ?

[SOCAL.M6.ZLE]

Originally Posted by Drnick

Question ;OEM clutches on ZL1, are they single disc
Or dual disc ?

ZL1 = Dual Disc...

[SOCAL.M6.ZLE]

Originally Posted by Sephx1

Well it is just never ending with this car, if you’ve seen my thread on my Copart build. Had a leaking crankshaft seal and replaced it with the LS3 seal today. When torquing the Innovators West pulley back on to the recommended 130 ft. Lbs, with the car in gear and the parking brake on, the engine would turn before hitting 130 lbs. rear tires did not move. Although it drives normal with no noticeable slipping, it should not do this.

Does anyone have a recommendation on a replacement clutch? I plan on using the car on the street and road course track says.

You really should use a flywheel lockout tool when removing and installing a balancer. Thats A GM SOP

[AZ_1LE]

I'm pretty sure the OEM clutch uses centrifugal forces when spinning to provide more clamping power. I'd be real surprised if it was bad unless it has some sort of failure in the pressure plate (or disc?).

[1wraith76]

Originally Posted by Sephx1

Well it is just never ending with this car, if you’ve seen my thread on my Copart build. Had a leaking crankshaft seal and replaced it with the LS3 seal today. When torquing the Innovators West pulley back on to the recommended 130 ft. Lbs, with the car in gear and the parking brake on, the engine would turn before hitting 130 lbs. rear tires did not move. Although it drives normal with no noticeable slipping, it should not do this.

Does anyone have a recommendation on a replacement clutch? I plan on using the car on the street and road course track says.

I have an unused stock clutch if you are interested. I went with a tripple disc instead. PM me if you want it.

[Drnick]

Originally Posted by SOCAL.M6.ZLE

ZL1 = Dual Disc...

Twin disc! Well that explains why I feel a difference
Between all my other car’s clutch engagement and
The ZL1.

[Rock-It Man]

Originally Posted by SOCAL.M6.ZLE

You really should use a flywheel lockout tool when removing and installing a balancer. Thats A GM SOP

Originally Posted by AZ_1LE

I'm pretty sure the OEM clutch uses centrifugal forces when spinning to provide more clamping power. I'd be real surprised if it was bad unless it has some sort of failure in the pressure plate (or disc?).

This and this.