[ha_pe_1968]

Hi!

Please help me i need an advice:

I have a SPF Diamond edition and a Roush 427R. The carburator is
the 870 Holley Street Avenger. (car has 5700 miles)

We were testing the emissions today and seems that i have a problem:

When the engine is hot i had this result:

idle : 900 rpm, CO 4%, HC 4000ppm
at 2000rpm, CO 7%, HC 500ppm

normally the CO at 2000 rpm should be below the result at idle.

When the engine is colder the HC is better (around 2700ppm)

What would be your advice to do? For me it sounds like a carburator problem but i am not sure.
If it is the carburator could it be the powervalve or where can i start to search?

Thanks a lot for help

Peter