On our 70 RR I had the flywheel lightened but it was starting at 40 pounds. I felt the improvement was worth it. I notice you stated that the Hays site recommended steel flywheel or steel insert. Well, that is what you will have with the aluminum flywheel with the steel insert, so you are good there.
What type of disc is the 930 series? Is it sintered iron? I tried to find it on the Hays site but they do not admit it exists as far as I could find.
We have a Tim Hyatt built slipper clutch based upon Mcleod components. It is adjustable with a sintered iron clutch so you tighten it up for the street, loosen it for the track. We run a 4.3 rear in our RR so I do not know just how bad the 3.55 will be. If you have to slip a sintered iron disc on a regular basis due to the 3.55 it will not last long from what I have been told by people more informed than me. Go to UMTRnorth and give Tim Hyatt a call, his phone number is on there. He might be able to set you up for less than you think, even if it is just the disc. You might be able to get a Mcleod disc through him for the cost of the RAM. The Mcleod I believe are considerably thicker so last longer.
Another thought, you have not mentioned what you have for a pressure plate. That is another part of the equation. Wound up for the street our clutch hits hard but the street tires will always slip to save the rest of the drivetrain. What I like about it is that the clutch will be there at the end of the night, it is tough.
UMTRnorth.com is a great resource.
Was your clutch slipping?
Last edited by David_in_St_Croi; 01/14/11 10:20 PM.