Will a bully clutch help??

Lkerley

Member
This clutch will be used for 1/8 mile racing.Both of my engines are stock lift Raptors with all the normal tricks billet Rod's etc.they both run right around the 6800 to 7000 rpm range with the gearing I run 53/13 currently. I've tried Hilliard,having the best luck with a max torque 3 shoes cut black spring with 2 coils removed.Will a disc clutch like bully give me the grab I need off the line better than other drum clutches which all suck.most torque converters give out at 4500 rpms.I need high rpm launches that grab and go.How many disc do I need with my motor setup?And are these clutches easy to set up and maintain.cheetah,Goldie locks,bully which one?thanks for any feedback
 
Not a cheetah ,
Bully or goldie locks .
Simple and easy to maintain not as easy as a drum .
I think either would do what you want .
Ive never ran our flathead clutchs over 4000 but the kt hits at 10,000 + .
So you can get pretty much any engagment you might want.
 
"High RPM launches"? Where does your engine reach peak torque? That's where the clutch should be slipping coming off the line! If yours is not coming off the line at peak torque, you do indeed need to work on that!
If it was me, I would try a three disc clutch.
I haven't heard anything bad about anybody's disc clutches.
Forget all you've heard about more discs accelerating slower, it's a myth. If it's not the biggest myth, it's very close. lol
 
Never heard that myth at all. Compared a 3 disk bully set to around 3800 for adult animal on methanol to a 9 shoe max torque made for snowmobile racing on the same track and the lockup from the bully always felt better but thats a roll start. Im sure the bully upgrade couldnt hurt. 3 disk may be overkill on the fathead though.

I think this is really cool though. Got any pics? Minibike im guessing?
 
Just changed this one from stock carb to the pz22 got it jetted right finally for next week.58 is it's best pass so far on stock carb.Im sure the pz 22 can improve that a bit :) gotta get a disc though.
 

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I think you will defiantly notice a better faster take off and harder initial hit with a disc clutch. Any of the bully/viper style clutches will give you both of those. The vortex disc will again give you a faster take off but it doesn’t have that “hit” it’s a real nice linear progression into lockup. What’s all done to the motor will let you know how high you can stall it up and still be effective for you. I think I have an extra 2 disc laying around I’ll look tonight.
 
You will see an improvement with a disc clutch. Enough return on investment for your application, I don't know. That would be up to you. You will definitely like the "feel" or "hit" of a disc clutch as it engages over a drum clutch.
3 disc is certainly overkill. 2 disc would be sufficient (1 disc would work if you're not making pass after pass without allowing the clutch to remain cool.)
I'll definitely agree though that you want the clutch to engage at peak torque.

We've always got used (fresh) disc clutches available if you need. Just give us a call.

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Carlson Racing Engines
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Thanks for response.No Dyno time so this is a guesstimate 4000-4500 torque peak.Is this a user friendly set up clutch? stall speeds ( bully).Can drivers be changed quick?being able to switch drivers in between will help me alot all I look for is getting the gear ratio as hi as I can but not sacrifice takeoff.I'm stuck now on 4.0.Im trying to get to around 3.73 ratio so I can do 1/4 mi passes.Would the 3 disc give a little more grab than the 2 disc for such a high gear? or is the 3 disc mostly for high horse power modifieds.thks again for help
 
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.060 stock lift...2 disc sounds good to me.I never tried one.My thought was at that high rpm would 2 disc definitely grab and hold when I leave.
 
Anybody have an infrared heat gun? Clutches generate heat, heat is a power loss, if a two disc clutch gets hotter than a three disk clutch, that means less power going to the rear wheels. No way to get around that. I have no idea if the two disc generates more heat than a three desk, but if it does............................... it's holding the same power as a three disk clutch, but with one less disk. I would think that would mean it's working harder, if it's working harder, more heat, more power loss. People go to much more extraordinary lengths to find less horsepower.
This is not a question of suitability for the purpose at hand, I'm sure he two disc can do the job, but does it do it as efficiently? That's the question.
 
Yeah that's what I thought to begin with around half of the max rpm's and that's about where I'm at with the max torque cut shoes and black spring with 2 coils removed 3200.Im happy with that but I have to get it to lock up.

My other motor I'm getting ready to rebuild for the modified class.I'm going with the 112 alt and big valves not set on the longer rod yet.I probably go 3 disc with it.I just got the head machined.Still a work in progress.Still trying to learn.
 
Anybody have an infrared heat gun? Clutches generate heat, heat is a power loss, if a two disc clutch gets hotter than a three disk clutch, that means less power going to the rear wheels. No way to get around that. I have no idea if the two disc generates more heat than a three desk, but if it does............................... it's holding the same power as a three disk clutch, but with one less disk. I would think that would mean it's working harder, if it's working harder, more heat, more power loss. People go to much more extraordinary lengths to find less horsepower.
This is not a question of suitability for the purpose at hand, I'm sure he two disc can do the job, but does it do it as efficiently? That's the question.
 
The 2 disk will be more than enough for that. I dig it dude looks like fun. 3 disk may grab harder but the extra rotating weight could create more drag from the extra disk and not enough power to overcome that. If you had an alcohol animal on there I'd say a 3 disk would suite it because of the torque the ohv engine will make compared to the fathead.
 
Yeah we have a couple animals on pump gas and one a Jimbo stroked build and the 3 disc works very well with it.Im not quite there yet😃 !!!
 
.060 stock lift...2 disc sounds good to me.I never tried one.My thought was at that high rpm would 2 disc definitely grab and hold when I leave.
I do run 3 HP flywheel with it does spin up quicker.Not that has anything to do with clutch issues though.??
 
either way, either motor, I’d be on a two disc with red springs and the air gap set up to hit a bit. Then just set your spring heights per the motors needs. The stock one 3500 ish the 112alt build 42-4500 ish
 
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