Will these lights be sufficient?

im going to grow 4-6 plants in a 15"x12"x27" grow box,and I have some 23 watt(100 watt replacement),2700k,1600 lumens,cfl bulbs(twisted,if it matters).Im starting the plants from a seed so will these be sufficient for vegetative AND flowering?If I use this setup,what would be the downsides? Also would I get a good yield?
On another note,what can I line the sides of the box with to reflect the light?Dont have much money for this so what are some household things I can use,or cheap things that are fairly common(live in a rural small town)?

FLAT white paint will work for the sides of the box or even mylar baloons cut them in half and use the inner part

If you have dollar stores near you, buy some silver mylar type gift wrapping. It comes either by the roll or in plastic bags of multiple sheets. Just paper the walls of your grow box with it (double stick tape works well for that). The CFLs will work, but from what I hear from veteran growers, if you want really great yields you need to save up for a HPS light for the best flowering results. For now, you can grow with those CFLs and still get bud - many on here do well enough with them. You really should pick up some 6500K spectrum though. Those are what you want for the vegging stage, and then you use the 2700K for the flowering. Look for bulbs that say "daylight" to find the 6500K ones. I'd be extra careful with the watering to start with - most new growers (me included) tend to over water at first. Do lots of reading...there is plenty of information to be found here if you take the time to read it. Good luck!

You probably want to use about 20 of those bulbs if you expect to get anything substantial.

If you have a menards nearby they sell 44 watters that work real well.

With a box that small, you may want to look at growing less plants. I'd say you'd be good with about...eh...1 plant in a 15 inch by 12 inch area.

Thanks guys for all the help,although I have another question.[See attached photo] Im using a speaker box and the woofer sticks out about 4 in out of the whole 10 in.,close to the top.Do I need to take out the speaker or can I just cover it in mylar?because it will be a bitch taking the speaker out and also preventing light from escaping etc. so I would prefer not to remove it

i'd take it out and fill the hole with cardboard