Engine & IMA battery weight

rmurray · 09-06-2009, 03:28 AM

Anybody know how much the engine & 5spd transmission weighs? Also, what is the approximate weight of the IMA battery and control electronics? I'm finishing my calcs on the needed horsepower (KWH) needed in two hub mounted dc brushless motors and I need the final gross weight estimate. thanks. Rich

biododge1 · 09-06-2009, 10:22 AM

The batt pack is about 60#. I estimate the engine,trans, to be about 250-350#

Willie Williford · 09-07-2009, 01:56 PM

Less than 200# is more like it.

Willie

**Hybrid-Battery-Repair** · 09-07-2009, 06:57 PM

Quote:

Originally Posted by rmurray

Anybody know how much the engine & 5spd transmission weighs? Also, what is the approximate weight of the IMA battery and control electronics? I'm finishing my calcs on the needed horsepower (KWH) needed in two hub mounted dc brushless motors and I need the final gross weight estimate. thanks. Rich

Officially, the engine is 128 lbs dry (probably sans accessories also)

The IMA battery is 65 lbs and the PCU, BCM, MCM fans and harnesses probably brings that to 95 lbs.

JimIsbell · 09-08-2009, 10:36 AM

Wow, I am stronger than I thought. I have been manhandling those batteries around for a few months now and estimated the weight at 45 pounds with the BCM, MCM and fans onboard. Now that I know the real weight I dont think I can pick one up anymore...#

**Hybrid-Battery-Repair** · 09-08-2009, 10:47 AM

Quote:

Originally Posted by JimIsbell

Wow, I am stronger than I thought. I have been manhandling those batteries around for a few months now and estimated the weight at 45 pounds with the BCM, MCM and fans onboard. Now that I know the real weight I dont think I can pick one up anymore...#

I ship enough of them that I know the weight. My UPS guy isn't happy on days when 5 of them show up, as he has to bring them down two flights of steps, and in the crates, they're 95 lbs.

rmurray · 09-16-2009, 01:08 AM

Thanks folks for the weight numbers. I was hoping the #s were high since going full electric with Hub mounted motors requires that I remove as much weight as possible. I am currently down to 1570 (while still being drivable). My hope is that removing the engine, trany, CVT axles, etc will drop 200, cooling system (w/coolant), gas tank, fuel system plumbing/etc, & 12V battery will drop another 20Lbs. Then I plan reducing about another 20 lbs in steering system upgrade (carbon wheel, manual light weight rack & pinion). That should put me at 1330 lbs (1570 - 200 - 20 -20). I plan to reuse the existing Nimhi battery (with new controls) until becoming operational and then jumping to Lion at same weight with added capacity and range.

I really was hoping to get down to 1200 where my two 7.5KW hub motors could power the conversion at moderate acceleration (ok, slow) and achieve about 60 mph (estimated given rolling friction with 1200 GVWT & low drag). I could upgrade to premium suspension and ceramic disks but that gets real expensive and want to put $ into the battery system. Maybe I'll convert the hatch to vacuum formed polycarbonate as the stock glass hatch is quite heavy.

I realize 15 KW isn't much prime mover power, but then I'm kind of a push the edge of the limits engineer (EE/ME).

Appreciate the help and feedback.

**IamIan** · 09-16-2009, 05:12 AM

Nice weight reductions... keep us posted on your progress / results.

**MN Driver** · 09-16-2009, 09:51 AM

This is a really cool project, and I never thought I'd hear of an Insight drop below 1500 pounds, but it's clear that it is happening for you. Great job, can't wait to hear more about this such as the hub motors and controller(s) that you are planning to put together for this, see pictures, and hear about the performance details when things are figured out. Is this going to be a front wheel or rear wheel hub design?

rmurray · 09-16-2009, 12:18 PM

Ahh, that is the question - whether to put the hub motors in the front or the rear. There are trade-offs and I am not yet committed. Here are my thoughts:
1) Front wheel mounted option -
+ closer unsprung weight swap since you replace the brake disks along with the wheel & axle assembly & you get a few pounds from the CV shaft too
- once the Engine is pulled, the front end is very very light and probably would need to move the battery forward to sit in the engine bay to offset both the unsprung hub motor weight and to keep the cars mass closer to center.
- only regen front braking (drums still in rear)
2) Rear wheel mounted option -
+ easier modification since the drum assembly is simply mounted to the rear swing arm
+ could probably still drive the car with ICE for a while during final EE system conversion
- only rear wheel regen braking (front disks still in place)
- front end will be very very light, possible stability problems including the fact more weight is now in the rear the physical brakes are in the rear
- increased unsprung weight in rear since the drum brakes are pretty light (~15 lbs?)and don't come close to offsetting the 45lb (each) hub motors

In summary: easier to put hubs in rear, but unsprung weight challenge & braking maybe a problem, hubs in the front better for unsprung weight change but creates very light front end unless I move the battery forward.

So anybody with insight here (sorry no pun intended) please give me your thoughts, I will post some progress pictures soon.
thanks, Rich