Ok I have been reading everything on this forum and others about clutching. I think I am starting get it but I think I need a little more help. I have raced in the amatuer ranks, did pretty good with lots a power but not knowing squat about clutching (only what people said should work but never did). I bought a tell tale tack and found my rpms don't build until after 60' feet or so. I tried many things most didn't work well, then I found this forum that has given me new great ideas that work.

Where I need help is understanding what to do next and why, I help a guy with a Dsa 809 c7 improver @208hp 9300rpms. He was using notch deeply 280s with a gold gold spring and the thing pulled the motor down to 7200rpms then climbs after 150' or so to 9300, after some head banging I came up with a ground ramp that I thought would work well. We lightened up the pin weight to 14g with 48/44 helix@20.5lbs and ran it. I think it was running 5.8s and went to the high side of 5.5 with the rpms shooting right up to 9000rpms then quickly to 9300rpms(good guess). We added some more pin weight until we loaded the motor down again, with the pin weight at 17.2ish it ran a 5.53 and 60' 1.44. The ramp I used is a 228 with the first 1/3 ground down and a notch, My next problem is what to do next.

1. Do I grind a little more off and add pin weight for harder pulling on the top end
easing it out of the hole a little and then pull harder by grinding down the
first 1/3 of the heel with a little just a little more notch. Will this give me a
better 60' and will a Thunder Shift kit help here?

2. Do I regrind another set of ramps with less ground off and add more pin
weight until I get the motor to stop bogging. Can I fine tune the holeshot
rpms with the clickers moving the ramp up and down a little and adj pin weight
to adj max rmps.

3. Did I get lucky and found the ramp I need and play with the secondary next.

My choice is #1 get it moving and then stuff everything I can at it without pulling the motor down. I am only working on the primary side. I will move on once I have fully got the front nailed down. I welcome any advice on this. I will be playing on the ice to prove or disprove all these theories.

Bubba

BUBBA
good to hear that you tune one clutch at a time, that's the way to go. what ramps have you tried? i have had the best luck with cf1's and px ramps, even left alone, i mean no grinding to them. the best spring i found for my sled is the old pink pink doo spring which is a 310-460. as far as the pin weight goes i found that 19 grams works well, with the ramp spring combo, rpm's went to the moon fast and then tapered off where i wanted it. havve you tried any of this in your application?? definately keep me/us posted on this. secondary i have had good luck with 20 lbs pretty much like you have with the new beige spring and a straight 50 helix. again, keep in touch. :D

Clutchman, I believe that PXs and CF1s and notched 280s and 228s where tried still pulled the motor down. Would I want to grind a little more of ramp to shoot the rpms up to 9300 (max) then pull down to torque then back up to max rpms or shoot up to torque then shoot to rpms.

I am I doing it right? I would like more pin weight but the sled didn't like that at all, is there differant way to get more pin weight to it. Everything I have read about pin weights on Mach Z's is around 19g-20g or close to that. What is your thought about this.

Bubba

Doo you have 286`s or 297`s available to you? , it would seem your thinkin the harsh drop off on the other ramps is boggin ya down.. Just a thought have you tried real light pin weight (to make it revvy) and taking out preload to load the motor later, I know that sounds odd but some combinations will work almost by controlling the top rpm (within reason) by light preload, its not a traditional tuning move but theres people dooin it. My other thought is trying a straight 44 or trying a seconday spring with more initial pressure, say a epi blue. So many things that might work in theory. Good luck.

ok... what is your gear ratio? the ramps you should be using are the 280s to start.. (my opinion). gears should be around 2.10 or so for that short a distance(500'). the cam seems correct(48/44) beige spring set it at about c-5.(20#) goodwin adjustable pins(18g.) to start with. run and see if clutches are warm... not hot. my .02.......doug. :dazed: