In a continuing effort to get the LT1 running better, I moved from dealing with timing and decided to start with basics. Just completed a compression test and seems consistent. new plugs with barely 100 miles aren't looking so good. Leak down next I guess.
-
-
Re: 70 LT1 compression test
#1 looks a little dark (maybe not a good pic?), but all the others look pretty good except that it is likely running a little lean and hot based on the whiteness. -
Re: 70 LT1 compression test
Thanks Ed. Here's a better pic of the plugs.
Comment
-
Re: 70 LT1 compression test
Dennis, like I said those look pretty good. Your compression test would also indicate no issues with rings or valves. I don't know what your rough running issues are, but I think you should be able to cure them by tuning since it appears your motor is probably mechanically sound. Setup the ignition timing per Duke's recommendations using total timing and mechanical advance all in around 2500-2800 rpm. Use the right vacuum can. Tune the carburetor per the book, make sure your jets and power valve are correctly sized and float levels right. Pay close attention to where the secondary butterfly stop is set (its a recessed set screw on the passenger side in the baseplate near the secondary throttle shaft); too much open and you won't get the idle air/fuel screw to have any effect, too little and you will get erratic idle. It may take a little time to get it all dialed in but once done you should have a smooth running motor.Comment
Comment