So, our Lotus Sport clutch failed at the LCS season closer……
We have been researching clutch options for some time. After some discussion from Kris Valdez at DRS several months ago, we set our sights on a set up he has been developing for the last year or so. A 7” twin disc Tilton unit. There were 3 main points that made this one stand out from all the competition.
1. Almost every race car on any grid at the professional level (F1, ALMS, NASCAR, etc..) has a Tilton. Tilton has earned an amazing reputation for quality and servicability. In fact all of the individual parts of the assembly are available as replaceable parts. This enables the clutch assembly to be serviced rather that completely replaced as you would normally do with a OEM style clutch/flywheel assembly.
2. It is a direct replacement. It uses the OEM throw out bearing, clutch master cylinder and slave cylinder. No fussing with hydraulic leverage and no need to adjust the throw.
3. It weighs 14lbs…yes, that is correct, 14lbs, oh yeah, including the flywheel…… and given that the clutch assembly itself is only 7” in diameter, most of that mass is very centralized. That is exactly half of the original Lotus assembly.
We had some concerns….
1. Would it be too much for the street? Not that the car is driven on the street that often.
2. Twin clutch assemblies rattle when they are disengaged (like a Ducati motorcyle). Would it be too loud?
3. Is it going to idle???? It only weighs 14lbs!!! Kris says yes…
Ok I’m in, lets give it a try….So, here is what we found….
Some people would not want to drive this clutch around town. Some people couldn’t, although it is reasonable to modulate, it only weighs 14lbs. I stalled it, a few times while getting used to it. After a few minutes of getting to know it, I was able to work it just fine. Actually I started to like it, a lot, yeah I would rock this clutch…. That being said, this is NOT a clutch for the daily driver, or for a car you just cruise PCH in. This clutch belongs on the track, but if you are one of those who wants to hop in your track day toy and cruise it around a bit on the weekend, it, would work.
The rattle is not very loud, nothing like a Ducati! I don’t think most people would even notice.
It Idles, actually I think it idles better that the Lotus set up. If you have an Exige S, you have had the car stall itself while coming to a stop. It seems to be part of the ownership experience. I have long theorized that the idle stabilizer valve is just a bit to slow for the extra parasitic drag of the supercharger. So it makes sense, in my own mind at least, that the lighter flywheel assembly would idle better. Who knows for sure, but it passed the idle test so I am happy.
We are headed to Buttonwillow tomorrow for a shake down… I’ll report back with my findings.
