I have an 87 GN that has been bored .30 Kenne Bell 260/260 cam MSD 50s KB stage III turbo (according to KB it is compairible to a TA49) 12inch 2800 stahl no cats no mufflers and the KB big valve heads ported and polished bosch fuel pump adjustible fpr set at 42lbs static. This is a two question post so here goes When on the throttle hard I can only get about 12lbs of boost before it starts to surge like it needs more fuel. I wouldnt think it needs more fuel with MSD 50s and also would you change the cam or the stahl to get more low end power? I was thinking maybe a 210/205 cam or a 4000 rpm 9 inch stahl.
Ed Bogard
Did you upgrade the fuel pump and wiring? Best diagnosis is to hook up a fuel pressure guage and take it for a drive. If the fuel pressure drops when your on it hard then either the fuel pump cannot keep up with the demand or there is a restriction in the fuel line (i.e. fuel filter). In my case it was the fuel filter. Hope this helps.
Thanks Dan but to answer your question yes I did change the fuel pump and the filter. I have a pressure guage at the fuel rail and one mounted to the hood shows real good fuel pressure. When I changed the injectors I put a fuel pump and another regulator on at the same time.