Questions and Answers

Oldsmobile Cutlass Carburetor Woes Q. I've had problems from many perspectives. After rebuilding the engine, I put a Edelbrock 350 performer intake on her. I could not get the stock intake to seal properly, and the replacement has solved that problem. I have split the exhaust and have converted to HEI with an internally regulated alternator and a used distributor.

I have removed the fan clutch for a flex fan. That is the extent of the modifications. My carburetor is the focus of my problems, I think.

I replace the rebuilt Q-Jet with an Edelbrock Performer 600cfm, electric choke, but the power loss was tremendous. Uphill traveling was terrible. And I could never get it leaned out. The exhaust was tremendously heavy. So, I went back to the Q-Jet. I have regained my power, but these Champion and Tomco rebuilds are so pitiful. The float has started sinking, among other issues.

Getting to my questions. I have had two Q-Jets on the engine and the Edelbrock. I've had the same problems with richness of the mixture. Swapping out the metering rods and jets have not helped. A friend has suggested a Holley, namely the 750cfm 80508s. But I don't want to spend the money if I'm going to be in the same boat.

Are my plugs mis-gapped? They are gapped as recommended. I can't remember the spark number or the gap number. Am I using the wrong carburetor? Have I lost my mind?

Before I had the engine rebuilt, these were not issues. And I had her rebuilt because of blow-by at the cam shaft and because she had been sitting for a while when I bought her. She had 78,000 miles on her when she came home to me.

I have considered adding MSD and a new distributor. Anything that might help. A new fuel pump maybe, although I replace that when she was rebuilt. I have no idea what to do. Please offer some insight. I'll take pictures of her, I'll send more info. I'll even come to where you're at and wash your car. Help me please.

• 1971 Oldsmobile Cutlass Supreme
• 350 Rocket V-8
• TH400 automatic transmission
• 101,000 miles Approximately 5,000 miles on rebuilt engine.
• 4bbl carburetor
• P/S and A/C

Stan

A. If the rebuild was just a stock overhaul and not race cam or different bore/stroke, a Q-Jet would be my carburetor of choice. But that's because I know how they work. They can be re-jetted to suit the type of driving for you. You need to start a log on what jets you start with and the next set you change to. Then make notes on how it drives and runs. Make sure the timing is set properly also.

Plugs should be gapped at 0.035" at least. With HEI ignition, you could probably open that up to 0.045".