I have a 998 lockup trans behind a 318, and put a Transgo shift kit in it. It has two problems. First, it won't shift at low rpm when first run cold. After a couple of minutes or shifts, it works fine, shifting at the right rpm under light load. Secound, and the real problem, even after some warm up it wouldn't shift from low to second and hit the rev limiter at 5400 rpm. A lighter load on the throttle and it will shift. Is it possible this thing is adjusted too tight on the trans to carb linkage?

It has been a while since I have messed with this, but if I am not mistaken, the shift kit will increase the internal pressure, then, as you depress the throttle, the pressure increase as pedal increases via the kickdown linkage (delaying the shift).

I cannot find a link to the kickdown linkage adjustment procedure, however, I always struggled to find a happy medium between good WOT shifts and not shifting too early at part throttle with a shift kit.

Shorten the TP linkage just enough to get the WOT 1-2 upshift.