joomla virtuemart site loading issue

I have a Joomla site, integrated with virtuemart in it. have almost 9,000 products.

it is not loading the site when i select a manufacturer from a module, which must list all products. Same problem is in the case of categories(have 2 categories).

error is FastCGI Error Number: 258 (0x80070102)

when I have only 250 products, it was faster.

is there any way to overcome this issue otherthan changing the execution time?

With that number of products you should limit query and page the results... No one wants to see that number of results.

You'll be heavilly penalized by search engines also.

I really recommend a possibility of filtering products and paging them. You might have to tweak vm code and/or use plugins though