I have an LT1 T56 I am planning to put into a 78 Firebird. It will be going behind a late, full roller 1 piece RMS SBC (not yet acquired). The plan is to use the LT1 bellhousing, flywheel & clutch. In other words just bolt it up like it was to the LT1.
My question involves clutch slaves. The bell is set up for an external slave because that is what the early (maybe all) LT1 F body's used. But the internet makes it seem as if everyone is using hydraulic TOB's instead of external slaves these days. What is the advantage? Is it just header clearance or is there something else I'm missing? Is there any compelling reason to get a hydraulic TOB instead of a $20 external slave?
I break clutch forks and pivot balls with distressing regularity. Even after welding the pivot balls up solid and reinforcing the forks as much as possible.
No linkage means no problems.
This is not with a T56, mind you, but I'm also not running the kind of pressure plate that a high torque V8 might require, either.
If it was me, I'd go external. My only reason is I have had more problems with slave cylinders than I have with clutches. I would rather have it out were it's a serviceable part without pulling the transmission.
Aside from adding a part to break(the fork), I greatly prefer the external setup for its serviceability.
How often are you guys replacing TO bearings that service is an issue?
A Tilton hydraulic TO mounted to the bell housing and properly spaced is a pretty simple, fewer moving parts, no real service, nothing to break solution. I put a SS brake hose on mine that extends out a hole in the bell housing and has a bleed screw in it for the only service it could ever need in the life of an ordinary racing clutch.
What serviceability are we talking about?
Throw out bearings? None, I've never even had one make noise.
Slave cylinders? I've had several develop leaks and need replacing long before the clutch is worn out.
I've never killed a clutch or TOB, I've had hydraulics and cable issues on every stick I've owned.
The only problem with the LT1 setup is the clutch is a pull off style, the TOB pulls the clutch towards the trans to release it. So a traditional hydraulic TOB won't work.
I was just in the workshop looking at the T56 and came to the same realization. Hydraulic TOB won't work on a pull-style clutch. Oh well one less thing to worry about.
But if you convert to a push style clutch, you won't have to drop a huge chunk of money every clutch change. The pull style clutches are extremely expensive for whatever reason. One advantage of the LT1 is that it's a small-block in every way except for the stuff on the front of the engine, so you can use a small-block flywheel and clutch setup.
For what it is worth, I never seem to wear clutches out, but I have the trans out 2-3 times per year to replace the linkage.
I am slowly converting all my clutch hydraulics to DoT 5. This should eliminate my problem with slave cylinders going out on me every 100K miles or so.
