Idle problem

[redsand]

I have a year one 350 crate with a quick fuel 750 carb with electrical choke which I had to remove to fit into the vortech supercharger cabinet. The supercharger is currently not hooked up. Took it on the maiden voyage and all was well until I put the car back into park. In park the car progressively increased rpm and would not go back down by tapping on the gas? When putting it back into drive the idle dropped and it was fine. As soon as I put it back into park same thing happoned again?

Any ideas why this would be increasing in rpm while in park?

[GM Muscle]

id get a new carb gasket and retighten it. sounds like a vacuum leak. i would say the fast idle was affected by the choke removable but if it idles fine in drive i would still lean towards the carb base leaking.. let the motor cool down and spray a small bit of b12 around the base. see if the idle changes. if it does theres a leak..

[chr2002ca]

Yep, my guess would be a vacuum leak also. Check for any cracks in your rubber vacuum hoses and any rubber caps you placed on your vacuum ports. One day I forgot to put a cap back on a small manifold port while I was testing and it did actually idle a bit higher because my engine at the time was running a little rich so it enjoyed the extra air. However, on a different day, when I was driving around the block, the plastic power brakes vacuum nipple coming off the brake booster cracked and my engine choked on all the extra air and dropped idle. So it all depends. Good luck tracking down the issue! If you find out what it was, let us know.