Who's running a Weber?
Went with a 38/38.. Now I wait
Be sure and plumb a fuel pressure regulator into your fuel line. Weber needle and seat requires max 3-1/2 PSI. Some will tolerate up to 4-1/2 PSI when new, but will eventually wear down and and flood carburettor.
Most 38 DGAS (water choke) and DGES (electric choke) carbs come jetted for 3.0 litre engine. Should be close enough for baseline jetting with 3.7 litre 225 slant 6. Original 38 DGAS had 27mm chokes (main venturii). Some of the newer ones have 30mm chokes but come with same (too lean) jetting, so you may need to bump idle (slow running) jets from 45 to 55. Idle (slow running) circuit on Webers run carb to around 2,500 RPMs before transitioning to main circuit. If main circuit is lean following idle jet change, leave 145 main jets in place and swap out 185 air correctors for 175s. That should get you pretty close......
http://www.lcengineering.com/LCTechPages/pdf/38DGAS.pdf
Best regards,
Harry
P.S. >>> If you keep about 4" long stub of original 2-1/4" OD headpipe where it bolts up to exhaust manifold, 2-1/2" OD tubing fits over 2-1/4" nicely. Just slip 2-1/2" tubing over stub about an inch and weld it up. Run 2-1/2" single exhaust with good 2-1/2" turbo style muffler and you are good to go.
