!PICTURES! big plants small pot. slow flower . light cycle?

[perfekto]

Hey!. my babies have been in flowering for about 3 weeks now and its realy going slow.. i used to have 18/6 first then they turned into flowering and plenty of hairs showed up so i turned it to 20/4 since i tought it would give me better yeild. some one told me at darktimes the plant has the highest resin product is that true?. should i be doing 18/6 again maybe it will speed up some? or what is realy the best light cycle.. short ryder nirvana autoflowering...

here's the picture... 3.7L pot's.. cant repot em during flowering since of the stress or do you think it wont be needing that it will be better with time if i change the light or dont i ?...
one of the plants is realy flowering realy realy slow compared to the others... and even the others seems to be slowing down is it couse of the pots or the light? here's the picture... the one that is nearly done is a lowryder that realy took off!!!!

http://imageshack.us/photo/my-images/545/imag0076ia.jpg/
http://imageshack.us/photo/my-images/268/imag0075gn.jpg/
http://imageshack.us/photo/my-images/580/imag0068un.jpg/
http://imageshack.us/photo/my-images/443/imag0074e.jpg/
http://imageshack.us/photo/my-images/685/imag0070cg.jpg/
http://imageshack.us/photo/my-images/259/imag0072cf.jpg/

i have growed before and never had this kinda problem. even tought the pot might be to small they should be flowering and be done in the future shouldent it?. or will they be like this forever until i repot?
http://imageshack.us/photo/my-images/202/imag0071be.jpg/

 

[*mr.mike*]

They're AUTOs... Why 18/6???

Better yet, why 20/4??

You want bigger? Longer light. Like 24 hours long.

Really, they'll fatten up wicked in the 7th week or so, so don't worry.

I've grown autos a long time, and 24 hours really is the best, for several reasons, oft argued reasons, but good reasons.