Originally Posted by
fpart
I was wondering, I have a WS7 L2G in my eight 2.0 truggy. It runs great. I am running Byron's gen2 30% Nitro with 9% oil. I didn't add any shims from stock because most people told me most fuels that say 30% are really like 25-28% nitro. My motor ran great all year making me think these people were right.
I was told the EBMods fuel uses real 30% nitro. I was planning on switching over to it next year and wanted opinions?
If you ran the Byrons Pro Driver 30% and it worked fine you should not have anything to worry about. Even if you do end up with an extra 2% nitro with a fuel switch you should not see any issues. From time to time when you are putting after run oil in your engine check the top of the piston. If you see pit marks on the top of the piston that means the engine was pre-detonating and a head shim should be added.
There are a lot of things that go into deck height/shims. When a company tells you that it is shimmed to run 25% nitro, that means 25% at sea level. You could be in a situation like me where I run at 5,000 feet above sea level. For break-in I will leave the headshims stock, once fully broken in I actually remove the thin headshim from the buttom leaving only the thick shim. I also run 30% nitro and a hot glow plug with this combo and never have pre-detonation issues. You also need to take into account what temp glow plug you are using as this can also change what you want to do. Going hotter with your glow plug is a little bit like lowering the deck height, and it's going to cause the fuel to ignite a little bit sooner. When making any changes like this you should watch things closely to ensure you do not have any pre-detonation occurring.