View Single Post
TurboKraft TurboKraft is offline
TurboKraft's Avatar
Join Date: Mar 2005
Location: Phoenix, AZ
Posts: 2,774
Hi, not bashing Spec at all; I am saying that in our experience they don't work well in these cars.
"Speed Academy installed it" -- okay, really *we* installed it :-) and ultimately no, not happy with it. It had a high torque rating advertised and failed to come anywhere near that, slipping on both the dyno and the street. We had to keep the boost turned down on Pete's car.

Another customer brought his near-stock 1986 3.3L in for a simple 3.4L rebuild with sport cams and the typical performance bolt-ons. It had a Spec clutch rated for far more torque than the CIS would support, but again, it slipped. That was a CIS-injected engine, not EFI. The client obviously wasn't pleased, so we had to pull it back out and put in a Sachs clutch. Expensive, yes, but:
(a) much lighter, so rev-happy, better gear shifts as the engine's more responsive
(b) still as-stock pedal effort
(c) as-stock driveability -- not "bitey," no chatter, no issues.

Like Centerforce, most of Spec's "upgrading" comes in modifying the disc: stripping off the existing friction surface (which is currently very good from Sachs) and replacing it with their own. Last I checked, most of their different levels are just differences in the disc type. I know Centerforce also modifies the tall pressure plates a little for more clamping (not the low profile ones, last I checked), but I don't know Spec does anything to the clutch plates other than paint them blue.
Regardless, they haven't been good for cars we've built.

We'd make more profit selling Spec and Centerforce, and the KEP should be the easiest solution -- but the Sachs Race Engineering clutches fit perfectly, work perfectly, are very light, always hold, have a reasonably long service life, and have no increased pedal effort. I really don't see what more a person could want from a clutch.
When everything just works, I think it's worth the extra cost.
Chris Carroll
TurboKraft, Inc.
Tel. 480.969.0911
email: -
Old 07-10-2020, 01:30 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #10 (permalink)