performance cams

[rodman]

Wants ask about the performance cams. When you install the 43mm intake valve , and the d 37.5mm exhaust valve do you have too add more shims ?

[So Cal Mark]

sometimes yes, sometimes no. It all depends how deep the valves are put into the seats, the cam lift, etc

[rodman]

sometimes yes, sometimes no. It all depends how deep the valves are put into the seats, the cam lift, etc

could you grind a little off the vale to make up how far the vale seats in the head?

[BEEK]

Rodman, I have thousands of shims right up the road from you. i really suggest you come by one day.

[vandor]

>could you grind a little off the vale to make up how far the vale seats in the head?

You could if you are out of shim-range. But it's best if it's done by a machine shop, so you get a perfectly straight surface.
But a little would be about half a millimeter or so, not much more than that.

[rodman]

>could you grind a little off the vale to make up how far the vale seats in the head?

You could if you are out of shim-range. But it's best if it's done by a machine shop, so you get a perfectly straight surface.
But a little would be about half a millimeter or so, not much more than that.

would you happen to know the spec on the stock cams?

[vandor]

Which specs? Timing is 5-55, 55-5 at the large clearance that Fiat used to measure valve timing.
I don't know what it would be at running clearances.

[Daniel]

would you happen to know the spec on the stock cams?

(off the top of my head) the lift is 9.3mm

[FiatMac]

I just measured a stock cam profile. Lift was measured at the cam follower. Gross lift was 9.55mm. Corrected for .018" lash (0.4572mm)the lift is 9.0932. At this lash the timing looks to be 30/70, 70/30 @ 110 lobe center. If I plug 0.050" lash into my spreadsheet, then I get 5/55, 55/5 (within the measurement error) as Csaba stated above.