gorms

Well, I found out the hard way how to abuse a clutch! First sled pull with the 5 spd, and I definetley broke something in the clutch. I wasn't sure how it would act in the pull with a clutch anyway, so I pulled in 2nd 4HI. Also not sure of the weight of the trailer, the answer I got was "same as the super stocks, about the weight of a 3 bedroom house" which I don't know how much that is!

Anyhow I thought I just didn't have traction, felt like I was in 1st gear. Made it past the 100' mark, and I noticed the tires weren't spinning at all, just creeping along, so I let off. First 30-50 feet was feeling real good though. Was sticky shifting after I stopped, then by the time I got to the pits I couldn't shift at a standstill, clutch dragging. I then poked my head under and in that tiny little weep hole I saw a few gumball-sized chunks of friction material. Had 5k mi on the clutch/tranny.

Needless to say, I just got in from the tow truck and I'm already planning for the next pull, just don't tell my wife that. I had a stock size Valair full ceramic, supposedly rated for 550/1100 with a 3800# pressure plate. I'm thinking dual disc, as I don't drag race and I shift slow anyhow. Of course I'm on a budget, so I'm thinking of going back to a valair, even though I think there are better options as far as quality. Anyone have some insight on these or other clutches? I'm still on stock turbo/injectors, probably won't change them out anytime soon. I do occasionally tow a 8k lb trailer, which I didn't care for the full ceramic so much with backing that up, but held fine anyhow.

Thanks again, and lesson learned on my part!

dieselfreak21

Pull in the low side next time. 4th low in the 5 speed is recommended if you have the power as it doesn't get its power off the counter shaft. 3 low works well to. Usuall they set the sled from 30k-40k depending on the class or opperator. I take it your rode the clutch some in the begining? I haven't heard bad things about valair duel disk. Backing up with a heavy trailer and a duel disk usually requires low lock . Most due disk will require an upgraded input shaft on the nv4500 if you haven't done it already. You might look at Kenny's pulling parts as well. They have very street friendly triple disk.

Tate

Definitely go with the dual discs. Single disc clutches just don't take the slipping as well as a dual does.

gorms

This was a single disc I destroyed. Took the clutch out yesterday and it did a pretty good job on the flywheel/pressure plate, looked like 3 matching hot spots painted on. Friction plate was down to almost nothing left (except the rivets!), with large bits of facing missing. I did slip it just a bit off the line, just enough to get it moving, and boy that sucker was heavier than I expected! Last year with a slipping auto it walked right out to 272', and for some reason wouldn't stay out of 4th gear under heavy throttle (later lost 4th gear) . Inexperience rules here I think, too much throttle maybe. I launched it at about 24-2600, and eased the throttle out from there.

I'm a little surprised it let go so much with NO smell what so ever. I've run a slipped clutch before, and it always smelled almost instantly. Maybe its a ceramic thing.

Thanks for the tip, never thought of all the stress running through the counter...I was just looking at my wheel speeds when I decided.

Anyhow, no work last week so no pay check this week stinks real bad, let alone for the toys. I'd love duals, but we are going on our honeymoon in two weeks with the camper, and I need something quick and cheap, I know bad combo! May just end up with a NAPA or something and go easy till I get the clams for a dual disc. I do want something that will last, truck is paid for so I'd like it to last at least a year or two! Thanks again for the help!