I have an 87 mustang Gt, with factory t-tops. I pulled the factory engine and replaced it with a newly rebuilt 302 boss. it's punched 40 over and has a drag racing camshaft with somewhere between a 1 and 2 inch lift. my problem is that it idles at about 1700 rpm. I have tried to adjust the carburator but 1700 is the lowest it will stay running.

it likes to run at about 2100

also when I brake it tends to die. at either Idle speed.