86 interceptor 500 , runs great all cylinders are firing, spark plugs also look good- might be running slightly lean, but I prefer that. BUT top speed is only 105 mph - seems like it’s dogging from about 90mph on up.. What do you guys think? Sent from my iPhone using Tapatalk
Time for a compression test. low compression=low performance. redlining an old 500 poses a risk of valve damage, engine blowup.