Alright, here's the deal:

A friend of mine from college here just purchased a 91 RX-7 NA. It had a blown front rotor and he dropped in a used 89 motor.

Thing runs great when you are winding up the rpms.

But, the idle is really rough and the thing reeks of gas when you open the hood at idle.

I will be going down to his place on Fri afternoon to help him out.

What suggestions do you guys have to start checking first?

Here's what I plan (new to the whole S5 thing myself):

check plugs
pull O2 sensor
unplug secondaries to see if they are leaking.
try to fiddle with the A/F screw to see if we can lean it out a bit.

Correct me if I am wrong with any of these thoughts and add your own too.

The timing was already set to spec according to the Haynes manual and we will be consulting that come Friday afternoon for other suggestions.

 

If you smell gas... double if not triple check that the pulsation damper is not leaking. It happens on the series 5 cars and will cause a fire just as easy as the series 4 versions.

I would also check to see if the charcoal canister is still there, sometimes people remove them or forget to hook them up when changing a motor and that will cause a fuel smell.

As far as the idle... check the basic things like a misadjusted TPS, a vacuum leak, ACV.

 

check the injector o rings too.

 

Alright newly compiled list of suggestions:

check plugs
pull O2 sensor
unplug secondaries to see if they are leaking.
try to fiddle with the A/F screw to see if we can lean it out a bit.

Added:

Check pulsation dampener
Charcoal canister
misadjusted TPS
vacuum leaks
ACV
Injector O-Rings

 

messing with the a/f screw or rich lean screw will not help the smell go away mine is turned halfway between stock and rich and the smell never changed but mine doesnt smell like gas anyways

 

Any other suggestions?

I will prolly be showing up at a local rotary shop on Friday night with this thing if we can't running proper ourselves.

Thanks so far guys.