[VintageLambo] Re: Jalpa Twin Turbo Project

Hi Fred, Well, I had to re-read my own web-site and I would go up to 6 cam degrees, downward adjusted for the adjustment quantization of 1.6 deg (i.e. between 4 and 6 degrees cam advance relative to spec). However, as mentioned on my web-site, it is very important to double- check the intake valve to piston clearance at a crank angle between 5 and 10 deg. ATDC, which is where the clearance is minimum. The clearance can be checked by parking the crank at that angle and pushing on # 1 intake valve follower with a soft tool (takes 100+ ponds) until it touches the piston and at that point measure the cam to follower clearance. You can also start out measuring that clearance and see if it is safe to reduce it by 1 mm (quite accurate number for the 6 degree advance). What a safe clearance is, is an engineering judgment based on the oil film thickness in the con-rod bearings, its minute stretching (which can be calculated), head gasket seating, etc. In my judgment a .060" clearance provides adequate safety. Best regards, Laust > So I can advance the cams on my stock 400gt motor and increase the > torque with no bad side-effects?(That"s a restatement of fact, with > a reasonable assumption, not a question...) > > How much should I advance them?I"m assuming you mentioned that on > your site, and I"ll take a look.But does there seem to be a > good "safe" number that would do the trick without getting too > extreme? > > > Best, > > Fred