EV Trans Am

So I got everything back together and we were able to do two laps in the neighborhood today.  It went much smoother with the flywheel vibrations taken out.  The rear suspension stiffening helped out but there is still some clunking and binding when first starting out.  The car is back on the ground so I’ll squirm under there and measure my angles again later this week.

A good idea would have been to measure them before we pulled the engine, as well and the ride height.  Troubleshooting will consist of adjusting the angle of the motor itself via the motor and transmission mounts and then adjusting the ride height by increasing or decreasing pressure in the rearairbags.

I’m sure a full suspension refurbishing and some subframe connectors would help too, but that will have to come later.  As my wonderful wife says, this is the project that never ends.  So I have to keep coming up with more stuff to do, right?

What a work weekend. Yesterday I reinstalled the clutch assembly and partially bolted up the transmission. Also removed the old power rack and installed the new manual steering rack. There was a little more to it than I expected and the new tie rods didn’t align correctly. I’ll have a pro fix that for me.

Today I finished the transmission install, put the driveshaft and torque arm back on, reassembled the rear suspension to complete the air bag install and put the car back on solid ground. The batteries are fully charged and tomorrow we’ll go for a test drive to see how the new parts smooth things out. I spun up the motor with the balanced clutch assembly and it seemed smooth.

The driveline angles are somewhat better so hopefully that problem is solved also. We’ll find out tomorrow, weather permitting.

Trans Amped is currently up on ramps with the transmission removed and the rear suspension half put back together. Waiting on a balanced clutch & flywheel, stronger 3/16″ steel motor brace, install manual steering and it should be back up and running.

Vibrations aren’t good so I’ve been troubleshooting them. One of them was from the motor because it was the same in neutral as in gear. So yesterday neighbor Mike and I pulled the transmission and clutch assembly. I spun the motor up with only the adapter and it was very smooth.

My understanding of the stock gas engine was that it was balanced, but actually the flywheel was used to balance it. So the engine was out of balance and the flywheel was out of balance but when you put them together they were balanced.

So I installed the flywheel on my motor and it was unbalanced, resulting in us pulling it apart and redoing it. I dropped the flywheel and clutch assembly off this morning at a machine shop and should have it back later this week. They’ll take off the cast-in weights on the back of the flywheel then remove additional material as needed to balance out.

The other vibration is due to my driveline angles. I measured with a digital 0.1 accuracy angle level and the motor was about 7 degrees lower in the rear, the driveshaft level, and the rear end 1.5 degrees lower in the rear. Both are in the same direction ( \_/ would be bad, \ _ \ is ok, / _ / is ok, /_\ would be bad). This is due to both the motor not being mounted level due to the steering rack and the rear end overloaded with battery weight. I have some stiffer springs and air bags to install to restore the rear ride height and will have to see what I can do with the motor.

I’m still nervous about overcharging the batteries so I kept checking on them tonight. All of the regulators had red lights on so I know I need to get the pack charged up and equalized before I do too much more test driving and kill it. It took about 2 hours at 12.5 amps but all but one checked out and flashed green for me. Tomorrow I’ll give it some one on one charger attention to bring it up. The other 12 batteries are at 13.25 V resting, this one is at 13.15 so it’s close but I hate to leave the other 12 regulators in bypass while this one hokey pokes its way up. Total pack voltage is 172V using 13 – 12V DieHard P1.

Today I made a motor brace that will hopefully keep the motor from rotating.  It’s only 1/8″ aluminum, but that was easy to cut and bend.  If it works out I’ll have it remade for me in steel from Fabricator Mike for extra strength.  I also replaced the rubber bushing on the front motor mount with a coupling nut sandwiched between the metal plates.  Hopefully that makes it more rigid and will also keep the motor from twisting.

After that I of course had to do some more test drives to see if the modifications worked.  They were better than last time and I’m getting closer to isolating the vibration.  If is pin the motor with the car in neutral it seems off balance.  The flywheel and clutch could be the cause so to find out if that it is I will need to pull the transmission and spin the motor with the flywheel detached.  If that is the case I don’t know how it will be fixed.  I imagine a flywheel can be balanced off the motor.  If the motor is balanced and the flywheel is balanced then it should all be good.

The vibrations are worst in 1st gear and lessen as I go into the higher gears.  For neighborhood driving I realized it works best just to leave it in 4th (like most people say).  It is smooth and has no trouble starting from a stop in fourth.

The power steering motor blew another fuse, this time 25 amps.  I need to go to thicker wire before I try a bigger fuse.  I’m also seeing that manual steering with the power rack isn’t too bad so a manual rack is appealing because it has a higher ratio and should be even easier.  The bonus is that I won’t need a motor to turn the pump so the car will be quieter.  All that will be running at stop would be the blower for the motor and it is pretty quiet.

Batteries are charging, need to get them all the way filled up before I do anymore driving.  They dropped to 12.4 V after the first drives.

The speedomoter and odometer do not work but we went about 4 miles today.  Tried to install the ammeter but I was reminded that the controller has capacitors and slowly discharges.  It will do so through your finger if you present the opportunity.

Hood on, tires pumped and away we went.

Right around 7:00 we backed her out of the garage and went for a quick trip down the street.  The car moaned and ground about not being moved in 1.5 years but it at least went.  Our first design flaw was uncovered as the motor and transmission promptly rotated towards the passenger side about 5 degrees.  The shifter can only go into first and second right now.  I know a way to remake one of the motor braces to have more resistance to rotation pretty easily – weekend project I guess.

Overall we went about a mile and my wife got to go for a ride.  I’ll edit and upload some videos soon.

We’ve also experienced another surplus in the budget.  My wife bet my brother a quarter it would work and won!

Afterwards the pack voltage was the same (173) as before, so it didn’t drain too much which is certainly good given the short distance.  We might get 15 miles out of the pack yet.  I’m anxious to see what a fully charged pack and solid mounts would let it do.  I didn’t get on it too hard but it zipped along ok in 2nd.

The regulators gave me a little concern because they were all showing red meaning undervoltage since last charge.  I realized (I think) that they must have sagged during acceleration (V=IR) and increased current draw below 10 V.  Most of the green lights flashed at me though as the voltage came back up.  I’ll check them all out tomorrow and make sure all my connections are good.

Whew.

Well tonight I mounted the circuit breaker and a kill switch \ rip cord in the interior.  And it rained so no test runs.  Tomorrow is a no go due to scheduling, but I’ll at least pump up the jams, I mean tires, and add some rubber insulation around the rear battery pack.  Also on the list is reinstalling the modified phone cords I made last night and charging the pack up to full.  It’s currently at 165 V, about 12.7 each.  The battery manual says that 12.84 is 100% state of charge, so the pack should be 167V.  Charging voltage should be in the mid-14s so I’ll watch the charger close the first couple of times to see when the regulators are shutting it down.