First you have to be certain you have no vacuum leaks. No good doing anything until those are found. There's little chance anything to do with the exhaust system is going to make the engine run poorly. I run three Thermoquads and they are all great. Next, from your description of what they did to your car, I would have to guess that they screwed in the idle mixture adjusting screws and then to compensate for the lean idle, they cranked up the idle adjustment. This would create the leanest mixture at idle possible. I also know from experience that those idle mixture screwes have a profound effect on that bogging down effect when you press on the throttle. I'd start by seeing how far out those screws are turned. You can see them on the front base of the carb, they have springs on them. Turn each one in while counting the turns so you can turn them back to the same place if needed. Typically these screws should be between 3 and 4.5 turns out. Thirdly, get a new mechanic, this guy is obviously drunk. ----- Original Message ----- From: "Bruce Stubblefield" <audiblefeast@xxxxxxxxx> To: <mailing-list@xxxxxxxxxxxxxxxx> Sent: Friday, November 14, 2003 2:11 PM Subject: IML: 78 NYB CARB PROBLEM Hello everyone, I have carb problem with the mighty '78 NYB. Smog approval required that I spend a small fortune on a new carb. I had the work done at a local place that does only old cars, is run by a guy older than 55 and has done good work for me in the past. Bottom line, the car finally passed the smog, but now runs very poorly. The mechanic tells me that the severe exhaust leaks that the car has (manifold gasket, flange/connector after the manifold, resonator, etc.) cause the carb to perform badly. Does anyone know if this is reasonable? He also says that "none of these carbs for this car were ever any good." This sounds like nonsense to me, but the smog place claims to have screwed with the thing for 4 hours to get it to pass. The symptoms are rough ilde after car is warm and stalling when I punch the gas when the car is under no load(coasting or in neutral). Idle is also set way high, probably to mask the rough idle. Any comments? Has anyone had GOOD luck with replacement or rebuilt carbs for this car? If I take off all the smog stuff and plug up the vacuum hoses, should that help? Many thanks! Bruce S 69 coupe 78 NYB