Recently put a RB header on my 88 Vert, now it is so rich at idle i can't stand to have the top down. the car is stock with the header, presilencer, and no cat. Called RB they said it is normal to run much richer after the swap.... i had done this to a 86 and it wasn't this bad... any ideas?

 

Make sure the car is in good tune. Plugs, wires, filters, etc. Also check the CLT sensor to make sure it is not reading incorrectly and fooling the ECU to keep the car in warmup enrichment. If the injectors have never been cleaned, have them serviced.

But yes, it is normal for the car to stink after the cats have been removed. You probably didn't notice it in the '86 due to the roof.

 

The 88 has new plugs, wires, and the motor is only 30K old. When installing the header it came with the usual air pump block off and O2 sensor bung. the O2 sensor is installed, would this be part of the problem? Also what is the CLT sensor and where is it? I have the shop service manual, and am a little proficient in the rotor motor... but most of my experience is with the 1st gen with a Carb.... and i can understand a little rich but it is way way rich.

 

CLT = Coolant Temp Sensor. On the back of the water pump housing.

As the ACV is blocked off, the emissions system is essentially defeated. The car is going to stink as the factory ECU runs rather rich.

The O2 sensor should be installed.