# 1978 MGB conversion Planning



## akmd1 (Sep 23, 2008)

I have been reading for weeks and plan to start soon. I don't need parts for a while, but I thought I would put my thoughts down and see if the community thinks I am on the right track. After reading all over the interwebs and it would seem my requirements are not lofty and I might be able to accomplish the conversion on the lower end of the reasonable cost specrum (relative but still the lower). The car is a 78 MGB that has been converted to Chrome bumpers and was converted to a 2.8 v6 from a 89 Slomaro. I spun a bearing on the crank so the engine has to go. I also have the T-5 tranny from the Camaro. The cars weighs ~2200lbs.
Requirments:
1. 40-50 miles (could trade some range for speed as round trip to/from work is ~10 miles)
2. 50-60 mph
3. no vaccuum pump required as I will convert to manual brakes (already manual steering)
4. clutchless to fit t5, but I used a s-10 bellhousing to get ride of the 17% slant
5. DC-DC or dual shaft motor with alternator (not decided and need to here pro/cons)
6. Batteries. I know what I am thinking will be unpopular but I am going Lead Acid for now then saving money unitil either they die or I come up with enough money to upgrade to Lithium (maybe in a few years it will be nanotube constructed lithium super capacitors).
7. Charging system still confuses me. Maybe the product will be partially defined by number 6? I can wire my garage for 220.

Parts:
Motor: WARP or Kostov 9
Controller -need help here? 120-144V max
adapter and plate
DC-DC converter - I think I read is part of some controllers?


I have no real budget assigned (not meant as "no money"), but cost will always be considred and am while I am not looking to make a name for myself by doing a conversion for next to nothing I do not enjoy spending money without good cause (anymore )

Thanks in advance,
Andy


----------



## EVfun (Mar 14, 2010)

Everything sounds doable. 

Lead is going to be a problem for >30 mile range in such a small vehicle. It can be done, but you will be heavy and getting all the lead in there will be less than fun.

If you use the alternator instead of a DC>DC you will have the lights dim when you stop at a traffic light. That is really the main disadvantage, the other one being that you have to fab the hardware to mount the thing on the end of your motor.

I'm all for manual brakes, but if you have disc brakes they will be noticeably hard. Drum brakes have one shoe that is "self energizing." That is almost like a built in small power assist. If the factory parts are available for this change it shouldn't be difficult (or too hard.)

For those converting RWD cars with conventional transmissions and going clutchless I've often wondered why they didn't get rid of the bell housing too. The adapter plate would be longer and made from a piece of tubing but it would seem pretty simple based on to get the measurements to center everything up correctly. 

You must support the transmission input shaft with your shaft adapter. It doesn't need to be a bearing because it will never rotate relative to the motor, but it needs support for proper centering. The bearing just behind the oil seal the the transaxle will not be happy if it is just centered with the input shaft splines.


----------



## Woodsmith (Jun 5, 2008)

The MGB started life with manual brakes so it shouldn't be a problem. It will just mean a bit of effort but not too bad.

I'd happily convert an MGB but I would plan on Lithium for that range and speed. You could start with LA but if you were able to find used but ok Optima blue tops, at the scrap yard for example, then you could use them for your ten miles and then sell them back to scrap after they die and replace with more of the same or get lithium as the car has been 'proved' functional.


----------



## akmd1 (Sep 23, 2008)

Is it the small size of the car which would then limit the number of batteries (LA) or is it the additional weight that LA brings that would kill the range? Close to 30 miles would be liveable until Lithium could be procured. I don't mind iterating the conversion with upgrades starting with a system that can't achieve my end goals but could grow to reach them. 

Would a 96V 100AH Lithium battery pack connected to the Warp/kostov 9 and still undefined appropriate controller be a reasonable option to a higher voltage LA setup? I would lose some weight but also start lower in input voltage to the motor.

Conversion to manual brakes is a no brainer. Just some parts procuring/swapping.


----------



## Yabert (Feb 7, 2010)

> Would a 96V 100AH Lithium battery pack


That sound like a better idea for me! 

You will lose some range but the price will be nice (around 4000$), the weight going down (under 250 lbs) and the power go up.

But I think you can have a better set up with 144v 70Ah battery for the same price / range than 96v 100Ah.

To do the move, think about saving 4000$ in gaz.....


----------



## RE Farmer (Aug 8, 2009)

Yabert said:


> That sound like a better idea for me!
> 
> You will lose some range but the price will be nice (around 4000$), the weight going down (under 250 lbs) and the power go up.
> 
> ...


I agree with Yabert, higher voltage and lower currents is better. 

Also, LiFePO4 is the way to go. PbA start adding up to a significant proportion of the weight of lightweight cars like MGs. Additionally, the higher performance & range given the lifetime of Li vs. Pb definitely makes Li the way to go. Rangers and S10's can carry the weight of Pb plus they have a place to put them. The MGB would be severely hampered unless you just want a glorified "golf cart" to putter about town (i.e. < 5mi radius of home and < 30mph speeds).

If available cash is the issue, consider financing the Li cells based on what you'd be saving from NOT buying petrol anymore. The fuel savings can easily cover the cost of Li cells, and after 3yrs, start paying you back the cost of conversion.


----------



## akmd1 (Sep 23, 2008)

So I guess more reading is now in order. I umderstand the ROI that can be achieved but have to work harder to get my kitchen pass signed. 

Off to price li batts
.


----------



## EVfun (Mar 14, 2010)

Lead isn't quite a cheap as it initially looks. You end up beefing up the suspension, or at least replacing the springs. You may also need to upgrade other parts, like steering or brakes, to safely handle the weight. The batteries don't last all that long, few people get more than 5 years from a pack of lead. If you choose sealed lead acid batteries you have to invest in a battery management system and if you choose flooded lead the performance ends up being comparable to an old 40 HP Beetle (or you kill the flooded batteries in 2 years.)

Lithium is really a game changer. You can keep the weight near stock, minimizing or eliminating suspension changes (it still needs to be in good repair to minimize rolling resistance.) Your car feels a lot nicer to drive, without the portly feeling often associated with lead acid conversions. You can get reasonable performance with smaller cheaper parts because the car isn't so heavy. The upfront pack cost is higher. The rest of the conversion tends to be a little cheaper. I don't plan to use lead every again. 

You can easily find Lithium powered EVs cost a lot more. If you look at those cars, in most cases you find that they have the kind of range that was mostly a dream with lead. Lithium makes 80+ mile range practical, but a pack 1/2 that size can work well too (for 1/2 the cost.)


----------



## akmd1 (Sep 23, 2008)

Man Batteries are not an easy read!

I realize now that my original range/speed goals were lofty, If price is a concern. It is so now trade offs are in front of me. 

So now I think I like the idea of LI but still need to be concerned with cost. I think then what I can give up initially is range. I need the speed for the roads I travel, but the range had a lot of fluff in it. I can get by with 10 miles minimum but prefer 20. I used this link http://www.zuglet.com and a figure of 300 watts/mile. I think I like the headway 40152 choice as it would seam I can get build a 90 pack which is 45S/2P for 144v 30AH. Just above my minimum reqs for $2250. but I could increment to 45S/3p for an additional $1100. It goes on and up from there.

Headway seams to offer some flexibility that and ease for incremental upgrades in AH that say TS or CALB don't (it appears battery replacement is how you get higher AH). Did I understand the site I lniked to above or not? 

Thanks


----------



## Guest (May 23, 2011)

> I realize now that my original range/speed goals were lofty


A common mistake. One I made too. Guarantee you will want lithium. I purchased a 77 MG with Lead Acid and it was lucky to get 15 miles. I swapped out the lead with 38 100 AH Hi-Power Lithium cells. Power is only 120 volts vs 144 with lead and the car is lighter and goes faster and further. Cost was not too terrible either. Fun little car. 

Pete 

You might think of looking into buying a conversion already done but abandoned but needs batteries. There are some that could get you the needed parts but you only need to worry about batteries and chargers. You still need to know about what your buying but it is another alternative to get you into a conversion so you can get lithium and then have fun for a long time. No messy batteries to mess with either. Love lithium cells.


----------



## Yabert (Feb 7, 2010)

akmd1 said:


> Headway seams to offer some flexibility that and ease for incremental upgrades in AH that say TS or CALB don't


Yes, but Headway cost more per Ah.
You can have an Calb 144v 40Ah pack for the same 2250$.... and the Calb spec claim to be more powerfull than 40152 headway (<1m ohm for Calb 40Ah vs <1.9m ohm for similar 40Ah Headway). The main difference is the better cooling capacity of the Headway vs Calb (better continous peak power).

But any pack you will choose, you will abuse a lot of your small battery pack to go at 60 mph.....


----------



## akmd1 (Sep 23, 2008)

After playing with the Pack Statistics page I can see I need to convince the Governor that LI is a good idea. I like the weight of the 144V 100AH CALB pack. I am not saying I can loose that much extra change but 300lbs of LI would be nice. That is at least half the weight of a comparable PBA pack.


----------

