Just wondering what gear ratio should be run at I-37 for street stock, pure stock and about how many RPM's do they turn.

Depending on the class I would guess a final of 6.33-6.78... a pure with 6.78 and a good motor should turn about 6800... Streetstocks may turn more than that...

I have a 6.50 and turn around 7, but I suck too so you may want to get once of the front runners opinion....

I was running a 256 w/1st in a 350turbo and that was i think a 650 ratio, i was turning 6900-7000. I went to a 410 w/ 2nd gear (620) ratio in the same trans and now im at 6200-6300 on the typical dry slick track! This is a purestock car though, the street stocks will be a little higher i believe!

I have a llm with 6.50 gears and my car weighs 3100. I run around 6300 to 6600 rpms depending on track condition. I think a 6.50 gear is a good starting point for a gear choice! Just my 2 cents!