[Unique427]

Question for the experts.

In the coming months I plan to replace my clutch and hydraulic throwout
bearing. Current combination has served me pretty well but peak engine power
has been boosted significantly since this clutch was installed some years ago.

Engine dyno now shows 650HP and 640 LB-FT at the flywheel.

The question is should I go twin disc or stay with a stout single disc setup.

Here's the specifics.......

Engine/Drivetrain:
Engine - Ford Racing A460 bored and stroked to 516 Cu. In.
Bellhousing - Lakewood #15220 (requires 184 tooth gear)
Throwout Bearing - McLeod #1305 Bolt On Hydraulic
Transmission - Toploader // Close Ratio // 1-3/8" x 10 Spline Input

Clutch Options:
1) McLeod RST Twin Disc #6911-06 (twin organic 750 LB-FT limit)
Adapts to existing flywheel. Requires assembly to be balanced.

2) RAM FORCE 10.5 Dual Disc #80-2295S Kit. (750 LB-FT limit)
Steel flywheel with 184 tooth gear. Assembly balanced at RAM.

3) Centerforce DYAD 10.4 Dual Disc #413703360 (1000 LB-FT limit)
I've read on Centerforce website this combination can not have
a shim between the hydraulic release bearing and transmission.
Text is confusing as to whether it is not needed or just prohibited.
McLeod bolt-on throwouts use a measured spacer to set gap.
Centerforce appears to not respond to any inquiry regarding this.

4) SPEC Stage II #SF272CJ Single Kevlar Disc (697 LB-FT limit)
Internet review indicate reasonably good street characteristics
up to Stage II+. Kevlar discs require a LONG break-in period.

There's a host of other possibilities for single disc arrangements
handling around 500 LB-FT which I have ruled out for now.

The car is for the most part, street driven.

Any advice based on actual experience is gratefully accepted.

Thank you.