1987 k5 Blazer underpowered
 

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Hello, I just have a quick question about my blazer. Ever since I had it (6 months or so) the blazer has felt like its been sluggish, bad fuel economy and not doing what its suppose to. I wasn't able to drive it for the first 4 months or so due to me being lazy installing the transmission. But it just doesn't feel right. It should be a lot quicker imo considering my POS ford f150 with a 4.2 can easily outdo it on the roads. Also, I put $60 of gas into it (2.74 a gal) and drove it maybe 70-100 miles and it was already at a quarter tank. That confuses me a ton, no way a stock 350 TBI would do that right? So I think I adjusted the TV cable correctly, and I felt a bit of a performance increase when I did so. I just recently made sure that the fuel pump was getting enough power (12.8 volts) so that's great. Multiple times took off the distributor and cleaned it, spark plugs looked fine, definitely getting fuel up to the throttle body, for some reason has a backfire, smoke out the exhaust whenever cranked (starts). Not sure if that might help you guys determine anything but there it is anyways.

To put this all together, it is getting beyond **** gas economy and it feels slow and under powered. Any ideas very appreciated!