Bill had sent this to me off list as he was not sure if it was relevant. Here was his questions and my reply. We thought it might be useful to someone working with an Aerocarb.
"> Jeff: > I have an AeroInjector that I recently purchased new and plan to install it > on my soon to be completed Corvair (2700). I am using a fuselage header > tank and gravity fuel flow. > I've read comments over the past couple of years about the need to remove > material from the #3 needle to change the mixture. Seems like a black art. > > Have you read Jeff Schultz's notes on reshaping the Aerocarb needle > (http://www.sonex604.com/reshaping_needle.html)? Did you reshape the way > Jeff Schultz describes or did you try something different? > Also, you say that how you were removing material made a difference in how > the needle performed. What were you doing initially to remove material and > what did you change in the process of material removal to get better > results? > I'd appreciate any of your insights as I begin the process of mating the > Aeroinjector to my Corvair. > Regards, > Bill" ---------------------- Bill, I did not follow Jeff's article strictly. There are at least 3 methods I have seen written up. Like Jeff's engine, this one started to get too lean at about 3/4 throttle if set to idle properly. At first, I was using a small file and removing material from the point it started to go lean. That was pretty imprecise resulting in removing too much material and having a rich spot in the upper midrange throttle settings. On this last one, I took a piece of 220 grit sandpaper and put it on a flat surface. After running the engine and finding the point it went lean, I marked that and sanded from that point on. Each time I put it back in and repeated the process. Each time I remove the needle from the carb, I back it out exactly 11 3/4 turns and then put it back in the same number. That has yielded consistent results. BTW, I found that the needles are not consistent from one to the next. FWIW, Revmaster does not offer "numbered" needles for the Revflow. They ask you to run the needle you have and then report back to them with the results. They will then grind you a needle specifically for your application. I am going to touch base with Joe at Revmaster and see if he would be interested in grinding some Aerocarb needles. That sure would make life easier! This is the third Aerocarb I have owned. The first two worked perfectly on my VW with the stock #2 needle. For the last 5 years I have run a Revflow carb with very good results but switched it out for Mikuni Super BN for better fuel atomization. That carb will take a new learning curve, but at $180 shipped, they may make a great alternative. Jeff Lange
