Baxter

Your carbs definitely aren't synced, but I don't think that's it, given the sudden nature. I'd wonder about the floats. If you don't have 'em, consider installing grose-jet float valves. And see if the throttle shafts are leaking. If they were recently rebuilt, they shouldn't be, but leaky throttle shafts cause no end of SU problems. [plug]If all else fails, ask on the Classic Motorsports forums. There's some SU whizzes there[/plug]

Also... next issue of Grassroots has a 300zx buyer's guide. If you're interested but don't already get the magazine, you can go to grassrootsmotorsports.com and get a free issue. Do it soon, and you'll get the one with the 300zx stuff in it.

Yup, that's GRM publisher Tim Suddard's own Z. It doesn't get a lot of press anymore since it's basically done, but it does get used, it's as a really nice 240, and I don't think Tim has any plans to let it go any time soon. Actually, I think most of the recent stories on it have gone in Classic Motorsports. It was last in the November '07 Classic, where we did a story on giving it some more power. The full story (including a dyno run and links to the issues it's in) is on the Classic Motorsports site at the page others have linked to: http://classicmotorsports.net/project-cars/1970-datsun-240z/