How do you think your stitch gauge is? For lace I usually measure across and then count the loops on the needle since lace is so hard to count. If the poncho is as wide as you want it to be, don't worry about the row gauge. You can always knit more rows to get more length, but you can't change the width.
You also have to remember that after blocking, lace gets bigger. You might want to make a separate swatch and wash and block it to see how much it 'grows.'
"Trust the pattern!"
Time flies like an arrow, but fruit flies like a banana.
Hop aboard while we follow the cloud-covered van of knitting harmony, man!! Woooo!! --Hedgehog
IngridKH on Ravelry