[Buckstopper]

Been lurking a while and figured I should sign in. Not a 968 owner but thinking about it. I have a '71 914 that I converted to all electric power. The drive train is great but unfortunately the 914 has some issues and needs to retire one of these days. I am looking for a new car to transplant the drivetrain into and am contemplating using a 968.



My 914 is is powered by a 300 volt lithium battery pack and 1000 amp motor controller. The motor is a warp 11 HV and the HP and torque is similar to a stock 968 except that the torque comes on at basicly zero RPM so it snaps your head into the headrest off the line.



914 weighs 2700# in EV trim and the weight is split 48/52 front/rear and the pack is mounted very low in the car so the CG is literally at the seat of your pants. It's very much like driving a go cart. I'd like to set up whatever new chassis I find the same way by splitting the pack as needed to balance the weight. 968 weight is heavier and that is a concern so it would have to go on a diet with all things gas related disappearing plus some of the no longer needed sound deadening would go. I want a rag top which I know is heavier to start with.



I know that there will be a few Forum members that will throw things at me for even thinking of doing this to a 968 but I am thinking it would work well but have a bunch of questions. Please be gentle as you beat me up over this. My design goal has always been to build a poor mans Tesla. The 914 close and I am hoping a 968 could get me closer.

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[Langley968]

This sounds interesting...

I can't wait to hear other chime in and see where this goes!

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[Cloud9...68]

Wow, sounds like quite an undertaking. How much did that battery pack set you back? It will definitely be another data point in the raging "exhaust note" debate...

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[DaveN]

Welcome. That 914 issue wouldn't be rust would it <img src="/forum/images/smilies/968/smile.png" class="smilie" alt="" />

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[Rap]

Think this would make a 968 snap your head back off the line?

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[Monstrous4Banger]

Not sure how you could fit a 914 drivetrain in a 968, the 914 is midengine, and the 968 is front with a mid mounted trans, with a driveshaft/tq tube connecting them.

I wouldnt beat you up over it, but I would hate to see a rare 968 used for something like this(IMO, theyre all rare). Even if the car used is trashed......all the more reason to restore, and keep it porsche. I think its a really cool idea, just that NA 944's are a dime a dozen, and really cheap, and lighter too. You could even always make one look like a 968. If your going custom....go custom. It kills me to see people tossing anything but a Porsche motor in a 968, or even a 951. Trashed or not. My 951 had a trashed motor in it when I got it, renegade hybrids tried to talk me into a v8 swap, and yuck it up about how horrible, and unreliable the I4's are. I ended up having a 968ts replica motor built, and thrown in. I have 15k miles racked up on the 3.0 turbo now, and at least 50k, on other 944/51's Ive had over the years. So far, I havent found the I4 to be an unreliable motor at all, nor overly expensive. Belt changes are frequent, and can be spendy....although I can get a belt for 15 bucks, and <acronym title='top dead center'>TDC</acronym> isnt exactly hard to find, usually already marked from past services. Eh, Im ranting now. Anyway..yeah, I wouldnt call myself a purist, but definitely a preservationist. Id say a NA 944 not only is more common, but better suited for your needs. The later model 944's even have almost identical interior, swap some 968 door panels in, and bam...about 95% of the 968 interior. You could pick up a clean 944 with a trashed motor for 2-3k easy.

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[Cloud9...68]

Monstrous makes some good points.

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[Scott Collins]

Buckstopper,



Takes guts to throw up a post like that - credit to you.



On another thread, we've been discussing voting, without any guantlets being thrown down yet, so your question might be fairly innocuous compared to that can 'o worms.



You probably need to get connected with a 968 owner in order to move forward. The layout and design of the 968 is so different than a 914 that I think that there is no way without a redesign, considering the front engine - transaxle design of the 968. And once you begin to add the weight of the batteries, you'll need to consider where to place them in order to maintain the balance of the 968.



Good luck.



-Scott

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[Buckstopper]

Sorry for the slow response but I'll try to catch up. First - thanks for the responses and starting a dialog.



914 issues: rust? Yes, 914's don't wear out...they dissolve. Also the transmission doesn't play well with the high torque motor. Mine is a tail shifter and those didn't play well period.



Drivetrain: Perhaps I should have said motor but its more than that. Torque tube and manual transmission would stay in a 968 conversion. Could keep the clutch or not. The clutch is't needed to shift with an electric motor since the torque goes to zero when you lift your foot off the throttle and there is no engine compression. The motor just spins from inertia. The clutch serves as a safety mechanical disconnect if motor controller fails on. My system is DC. DC systems tend to weld themselves on when things fail. I also have two electrical disconnects plus a mechanical disconnect to kill power in the system if needed. AC systems blow up when they fail so retaining a clutch isn't neccessary with those.



Head snap: it's all about torque. Electric motors have a rather flat torque curve that slopes slightly down hill. The most torque is at the zero end of the scale. My existing motor and controller combination put out about 300 ft-lbs of torque from 0 to 5000 rpm. If I upgraded to a 1400 amp controller it would be over 400 ft-lbs. That kind of torque breaks things. So the limiting factor would be the torque tube, tranny cv joints and axle. How much torque does a built 968 turbo or supercharged engine put out? At what RPM?



968's are rare: I agree. They are also pretty well engineered. Should there be some preserved in concourse condition? Absolutely. Does that mean that none should be modified? I don't think that the majority of the members of this forum would agree that they shouldn't modify their cars because they are rare. That's the whole reason that forums like this exist and that nuckleheads like us still play with cars!



I am a long time hot rodder with permanent grease under my fingernails. That is why I got interested in EVs. Our world is changing and we as auto enthusiasts need to get out ahead of it. We need to be kinder to the environment. If we don't figure out how someone else will do it for us. As an American, I believe that we need to get off of foreign oil. Again, we need to figure out how or someone else will do it for us and I don't think we will like it. How can each of you be part of the solution?



Lastly - if you have a chance to drive or ride in a Tesla Roadster or a well built conversion, DO IT. You will have a big grin on your face because they are a lot of fun and can give gas powered sport cars a serious run for their money. I have more fun driving my little 914 than I have had with all the cars, jeeps, trucks and boats that I have worked on combined. It's a blast and that's what it's all about.



Dick Burnham

AKA Buckstopper



Ps. Missed addressing "why not do a 944?". Because 968's are pretty cool, right? I like the looks of a 968 and I want to do a Cab so I can put the top down on the three days a year that it isn't raining here in Oregon. I love to reach through the open roof and waive at the 911's that I pass in my 914. It really pisses them off (then they have to swerve around the rusty body parts as they fall off my car...)

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[Buckstopper]

Scott- I most definitely need to spend some quality time with a willing 968 owner and his car. I can't tell you how much time I spent staring at the 914 and moving things around. I am working on getting a webpage up with photos of the 914. I'll post a link to that so you guys can see how much stuff needs to fit in the car. A lot of it is the battery pack and it is boxy and heavy and rather unflexible. I welded up and installed several versions before I ended up where I'm at on that one. I hope I learned a few things and it won't take as many tries next time.



Anybody in the Portland area interested in opening the hood on their car for me?



Dick

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[tamathumper]

I think it's a cool idea!



I understand the conservation-minded approach, as I was the same way with my first two P-cars (e.g. "preserve them at all cost"). But this 968 is my third and I've taken the torches and grinders to it almost from day 1 to make it mine. And I've enjoyed it six times more than the ones I tried to preserve... And by the way, they fought me the whole way (they apparently didn't want to remain pristine examples of the marque because things kept falling off of them.)



I say go for it, and at the very least, there will be one less 968 in the population and mine will be worth fractionally more! <img src="/forum/images/smilies/968/biggrin.png" class="smilie" alt="" /> <img src="/forum/images/smilies/968/popcorn.gif" class="smilie" alt="" />

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[durtkillon]

Buckstopper, would the batteries need to go toward the rear of the car or do you build a pan up front? One of the reasons this car is so fun is it's balance. Lighten up the front and add weight to the rear and you may subtract from this car's best trait. That may not be important to you, but given you came from a mid engine car, perhaps it would?



I imagine the suspension has to be redone as well just to comensate for the weight differences. Would you expect the braking to change?



A decent 968 with 100K miles is worth about 10K. Find one with a broken timing belt and it's down to about $3k.

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[Buckstopper]

Durtkillon - great question. The answer is both. On my 914 I split my pack roughly in half and used them to balance the weight. I kept a spread sheet of everything that came out and every thing that went back in and where it came from...front or rear. I wasn't real scientific about it and guessed some of the weights. I ended up 100# heavier then I estimatedvbut the balance was good. 48/52 F/R.



I'd like to do the same with a 968. Fuel tank would go away and be replaced with cells plus it looks like there might be room in front of the rear axle axle in the rear. Up front the motor would go where the engine is now. My motor is 11" diameter and 24" long. The motor controller and other electronics can go right over the top of the motor perhaps in the are where the electronics are now. The rest of the space up front can be filled with cells. I really need access to a car to get some measurements to see where things could go.



Here is a link to my 914 website: http://www.evalbum.com/4059 (do a search on that site for 968's and you will see at least one that is underway. There are several 944's either on the road or in the process of evolving)



Everything blue in the photos are lithium iron phosphate cells. 94 total and they weigh about 7# each including an allowance for racks.



I am hoping to find exactly what you described. My dream car would be a red cab with a blown engine and a perfect body and absolutely no rust...I'm really tired of welding up rust holes. Has to be a 6 speed. Upgraded suspension would be a bonus as it will most likely be a little over weight. The search continues!



Dick

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[Langley968]

Just checked out the link you mentioned and checked out ALL the Porsche EV's! Wow! The 914 seems to have been a favorite. Must be due to mid engine layout...

If done properly, you should be able to maintain the "front/rear" weight distribution and thus keep the great handling the 968 chassis offers. Look forward to hearing your continued search results.

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[blau]

Here's a decent looking donor car for you....and a rare color to boot!

http://forums.pelicanparts.com/porsche-c...500-a.html

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[Langley968]

I think Buckstopper is looking for a "nice" unit that has a blown engine...

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