Need a recommendation on a clutch Options

[jtg]

Hi Guys. I need some help. I'm not experienced with clutches and need a recommendation on my 914 clutch. Right now I have 5000 miles since total restoration. I have increased the power of my motor and the clutch makes a bad smell every time I accelerate at max throttle. I have a new Sachs clutch and pressure plate. The clutch disk has the 6 springs and the plate has part number 3082 183 331. I believe it is the standard one now for 914's and the original one on the model 911T's. My motor is an electric (Netgain model Warp 9) that others have put on a dyno and it produces a max of 157 HP and 277 ft lbs of torque. Max torque is at zero rpm. Since I have recently upped the power I believe that is producing my clutch problem. (My power is easily varied via software in the controller.) I believe the original 914 engine put out about 138 ft lbs. and 76 hp. Using the Haynes manual I have checked clutch pedal play and adjustment.

I need advice on what to do. My 914 is to much fun as it is so I really don't want to reduce the power. I get 0-60 times less than 9 sec now with my weak driving skills and a slipping clutch. Can I accept a little burning clutch? Bad Idea? Change the clutch out for a stronger one (maybe Kennedy mk 4)? Switch back to the weak gas engine? Can anyone point me in the right direction?

Thanks in advance for any comments. This group has provided invaluable information during my restoration.

Jim
http://www.evalbum.com/3439

[mepstein]

Since you have torque at 0 rpm, Why not get rid of the clutch and go direct drive?

*disclaimer - I know next to nothing about EV's (IMG:style_emoticons/default/biggrin.gif)

[SUNAB914]

What about flywheel, was it replaced?

[jtg]

Thanks for the replies.

Some people go clutchless, some disadvantages though. At 90 mph on the interstate I need 4th or 5th to keep the motor under it's limit of 5500 rpm. Also at slow speed there is more cooling to the motor if I use 2nd or 3rd. Also with the clutch anyone can drive it at any speed, you don't know it's electric except for the lack of noise and smell.

Here's a pic of the clutch.




So I have the original clutch and flywheel. I didn't have the folks locally to grind off the gear.

Jim

[Ductech]

KEP quoted me that the stock clutch does not like anything more than the range of 180 foot pounds of torque. Sounds like a stiffer pressure plate is in your near future.... Or u could program in a little less umph and use up the rest of that clutch

[Andyrew]

I recomend giving KEP (Kennedy Engineering Products) a call and discussing it with them.

I use their stage 4 clutch, Its a bit stiff, but it holds my 375lb torque v8 just fine (I dont use first mind you). Im sure a stage 2 or stage 3 would probably work well for you.

Also your clutch will not last long if you can smell burning. It will glaze over or worse burn up all the material making it totally worthless and potentially damaging your flywheel.

[GeorgeRud]

Why not try a puck type clutch as they seem to hold better. They're a pain to start as they don't like to slip to engage from a start, but that shouldn't be an issue with the electric motor.

Show us pictures of your battery and other features on the car!

[Ductech]

And I'd wonder what the scale weight and average spirited run time thus far with your setup is?

[jtg]

Ducteck, Andrew, thanks for the advice about Kennedy. That might be the best solution. I never use first gear either. Total weight came out to 2570 lbs.

George, check out this link for pics and specs. http://www.evalbum.com/3439

Jim

[Ductech]

Dude that's a scary amount of money spent on batteries.... Although your Ev looks a lot cleaner than most I've seen.

[jtg]

Dude that's a scary amount of money spent on batteries.... Although your Ev looks a lot cleaner than most I've seen.

Yeah I was a lot of money. But I haven't been to a gas station in 2 years.

[brant]

I tried to post this last week but the system must have hiccuped...
I don't see my post...


my question to you is/was... when was the flywheel last machined?
was it done 5K ago?

your symptoms sound exactly like those of someone who mis-machined the flywheel causing the clutch to slip.

when was it machined?

brant

[SirAndy]

277 ft lbs of torque.

That is way too much for the clutch you are running!

I have similar torque numbers and i run a KEP Stage II clutch. You might even have to step up to a Stage III ...

(IMG:style_emoticons/default/popcorn[1].gif)

[jtg]

Brant; I don't know about the flywheel. It was the one on the project when I bought it. Thanks for the idea.

SirAndy; That's good to know. Thanks.