I have a 1971 FJ40 with the F135 engine. It runs fine, my son drives it every day (5,000 to 6,500 feet elevation) and it does some light wheeling in the mountains up to 12,000 feet. The ignition system is electronic; distributor from 1978 FJ40 and coil/igniter from 1984 FJ60. The current carb base does not have the ported vacuum, so the dizzy is only using mechanical advance. The VSV has been removed. The carburetor was rebuilt (not by me) about 18 months ago when I could not pass emissions. After the rebuild, a local shop was able to make adjustments to get it to pass emissions - but just barely. The best vacuum I been able get out of the engine is 12. I've looked for vacuum leaks (not found any) and have the valves adjusted to spec. The truck runs rich (you can smell it) and averages 10-11 mpg pretty consistently. I picked up the FJ40 because I've always wanted to learn more about auto mechanics and over the couple of years I've had my truck I have learned a bunch. While the truck is running OK, I really want to get experience rebuilding a carb. To that end I picked up a couple of carbs and rebuild kit a while back. They have been sitting around and now I'm ready to take the project on. My starting point is a H2662 model that has 2I4 (built September 4, 1972) stamped on the air horn. The carb base is not drilled for ported vacuum. The rebuild kit is in a old, beat up Keyster box from SOR which has many numbers; SOR 042-03E, Original Kit No. 04211-60142, Carburetor No. 21100-60202. 60203 and on the side the number K11-358A. While the box has seen better days the two packages with parts are still sealed in their plastic wrappers and in very good shape. I have a few questions regarding the jets to use as I put the carb back together. On the disassembly, I managed to mangle the head on the secondary jet and I did not realize the size of the slow jets was different. In short, I have incomplete information on the jets that were in the carb. I do now have some custom modified screw drivers so I'll not be making the trashed carb jet head mistake again. Probably not too big a deal because I am more interested in what jets should be in the carb when I put it back together. The jet sizes that were in the H2662 carb are: Primary Jet - 118 Spare in Primary plug - 060 Secondary Jet - UNK; trashed the head Spare in Secondary plug - 141 Power valve jet - 070 Slow Jets - 80 and 50; but I didn't make a note of which was on what side The Keyster kit has the following new jets: 114 - Primary 180 - Secondary 60 - Power valve 50 - Slow jet, but the kit only has one From some other carbs, I've also got a few jets of the following type and size; Primary/Secondary - 180, 159, 114, 103 Power valve - 070, 040 and 060 I understand that many variables come into play when deciding which jets are the best starting points for a particular carb, on a particular engine in a particular geography. As I've researched jet size, I have been able to gather that at altitude a smaller primary and power valve jets together with timing advance are the general direction to follow in optimizing a carb. Locally, MDH33 has rebuilt a couple of 73-74 carbs using; 112/114 Primary, 180 Secondary and 50/50 for the slow jets with good results. This seems like a reasonable starting point. However, given the subtle changes between 72 and 73-74 I am interested in input from the group as well. Given my situation, what recommendations would the group have regarding jet sizing as I put the carb back together? Is 103 a too small starting point for the primary jet? Even though I don't have one, should I look for a 112, 110 or 108 jet as the starting point?