I have an 88 Wrangler YJ with the 258 and the Weber carb upgrade. I did the nutter bypass and also installed an HEI distributor. I am having a very difficult time with the timing. If I set it to where it runs perfect, idles perfect, has the power back, it spark knocks at higher speeds. If I retard it to get rid of the spark knock, the idle goes away and the low end power goes away. I am still running the stock recommended spark plugs. With the HEI distributor and the nutter bypass, I am thinking that I should also be running with different spark plugs right? If so, what are recommended?