which Weber to use on my 87 yota truck swb single cab bobbed rear, 4x4, 22R with RV cam ,5 speed manual , stock tcase, 38.5 bogger (i run low range off road) , flowmaster exhaust , 456 gears locked, long tube header .... what weber would fit me best >>34,36,or38mm or 40mm or.....

 

With 4.56's and 38.5's, I'm gonna say a Holley 4 bbl on a small block v8. You're way under geared for a 22r at that point. The best you could hope for is a 32/36 with a sync-link installed to keep the intake velocity higher than a 38/38 synchronous. Higher intake velocity generally means better low end torque, but I still think you'll be wanting for more power from your engine, not your carb.