Home-made "FRUNK".......

[JerryB]

Not sure. I just fiddled through a load of odd bolts till I found one with the right thread, even though it was too long. It was all I had so I went to B&Q & found some of the same thread size and the right length. They don't sell these singly but you get a small bag for £3.80 & fill it with as many nuts bolts & washers as you can get in & still close the bag, so its quite a cheap way of getting them.

 

[toadinapintglass]

Went to two wilko's and couldn't find the box..Managed to pick up slightly smaller one from poundland...was 2 for £7.

 

[sgt4hed]

see now would it really have cost MG that much to put something like this in there? would have really added to the appeal of the car by not wasting all that space under the bonnet

 

[Spinynorman]

Great idea!
Find this in Wilko, looks like a good fit

Wilko 32L Modular Storage Box with Lid | Wilko

Shop for Wilko Modular 32L Underbed Storage Box with Lid at Wilko.com

www.wilko.com

These are now £4 @ Wilko…from 30 December 22

 

[TheArcher]

Excellent ideas. But - would there be problems with reduced ventilation, over-heating, rubbing on cables, rattling, access to the emergency shutdown - and lastly insurance kwho we all know make any excuse not to pay out)?

 

[Susanna]

There is no heat generated under the bonnet, and the box I bought just sits on metal. There are no cables in the vicinity. The type 2 cable is a pretty snug fit in the box, but even if there is any rattling, I certainly haven’t heard it.

Where is the emergency shut-down? I guess I ought to know where that is!!

 

[johnk]

I've been lurking here and learning for over a year (I waited 11 months for the car!), and decided it was "time to give back".

Various people have expressed concerns that a Frunc would increase the temperatures under the bonnet and potentially cause reliability issue.
Since the AC charger box does get quite hot to the touch I decided to quantify the issue.
I got a temperature logger and placed temperature sensors on the charger - one on each corner and one in the center.
To measure the under-bonnet ambient temperatures I also placed a sensor next to the windscreen washer filler pipe and another next to the 12V battery.
I also have a weather station so could match up the actual air temperatures during charging.

I made a frunc using a Wilco (20L 59x39x16.2cm) £5 underbed box as others have done, reinforced with 3mm ply and supported on 6 off 6mm Neoprene pads on the inverter and 2 thicker strip on the other (junction?) box.

I recorded charging at 7KW with No Frunc, with the frunc fitted, and with the frunc fitted but raised up on 12mm ply blocks (to increase the air gap and so give better air circulation/cooling).

The result is that the surface temperature of the inverter was increased by approximately:
1.8C with the Frunc just on 6mm Neoprene
1.2C with the Frunc on 6mm Neoprene + 12mm spacers
These are measured at the center, but the corners give similar results - just a slightly lower peak (even where the sensor was trapped between neoprene and charger).

I also measured the surface temperature of the plastic inside the frunc at the center of the charger - which was about 8C above under-bonnet ambient.

As a side issue the temperature under the bonnet rose by about 17C above the outside air temperature.

My conclusion is that the effect of the frunc on charger temperatures is minimal, and will have no effect on reliabilty, and that the 12mm spacers are not needed.

I'm leaving the frunc fitted with the 6mm neoprene only.
Overall I'm very pleased with the result - the only change I may make is to glue a cover over the hole for the cable, and add some padding if the cables rattle around - so far I haven't heard them.

I've attached a graph and some photos

P.S. The fixings are definitely M8, in my case with a threaded depth of ~15mm

 

[Lovemyev]

I've been lurking here and learning for over a year (I waited 11 months for the car!), and decided it was "time to give back".

Various people have expressed concerns that a Frunc would increase the temperatures under the bonnet and potentially cause reliability issue.
Since the AC charger box does get quite hot to the touch I decided to quantify the issue.
I got a temperature logger and placed temperature sensors on the charger - one on each corner and one in the center.
To measure the under-bonnet ambient temperatures I also placed a sensor next to the windscreen washer filler pipe and another next to the 12V battery.
I also have a weather station so could match up the actual air temperatures during charging.

I made a frunc using a Wilco (20L 59x39x16.2cm) £5 underbed box as others have done, reinforced with 3mm ply and supported on 6 off 6mm Neoprene pads on the inverter and 2 thicker strip on the other (junction?) box.

I recorded charging at 7KW with No Frunc, with the frunc fitted, and with the frunc fitted but raised up on 12mm ply blocks (to increase the air gap and so give better air circulation/cooling).

The result is that the surface temperature of the inverter was increased by approximately:
1.8C with the Frunc just on 6mm Neoprene
1.2C with the Frunc on 6mm Neoprene + 12mm spacers
These are measured at the center, but the corners give similar results - just a slightly lower peak (even where the sensor was trapped between neoprene and charger).

I also measured the surface temperature of the plastic inside the frunc at the center of the charger - which was about 8C above under-bonnet ambient.

As a side issue the temperature under the bonnet rose by about 17C above the outside air temperature.

My conclusion is that the effect of the frunc on charger temperatures is minimal, and will have no effect on reliabilty, and that the 12mm spacers are not needed.

I'm leaving the frunc fitted with the 6mm neoprene only.
Overall I'm very pleased with the result - the only change I may make is to glue a cover over the hole for the cable, and add some padding if the cables rattle around - so far I haven't heard them.

I've attached a graph and some photos

P.S. The fixings are definitely M8, in my case with a threaded depth of ~15mm

A very detailed study and results found, thank you !.