To increase Magento 1.x product title character limit
Navigate to: \app\design\frontend\default\theme692\template\catalog\product
Open list.phtml
Find the line code segment: ~line 235
<?php $small_getName = strip_tags($this->htmlEscape($_product->getName()));
if (strlen($small_getName) < 100) echo($small_getName);
else { echo mb_substr($small_getName, 0, 100,'UTF-8').'...';} ?>
Change the number 100 to 500 (or whatever number of character you want the title to increase to.
Depending on the theme you may need to change the below line
<?php echo $_helper->productAttribute($_product, $_product->getName() , 'name'); ?>
to
<?php echo substr($_helper->productAttribute($_product, $_product->getName() , 'name'),0,500) ; ?>
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