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phil, Chevy Mechanic
Category: Chevy
Satisfied Customers: 269
Experience:  20 years experience
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1985 chevy: im wanting to know the stock cam specs..lift..piston

Resolved Question:

im wanting to know the stock cam specs for my 1985 chevy 305........also do you know the most lift and duration that can be used without valve, piston problems..thanks a million

        &n bsp;                                                                                               Customer

                                      ;                                                                     humble tx
Submitted: 8 years ago.
Category: Chevy
Expert:  phil replied 8 years ago.



Can you tell me what vehicle the motor belongs to and what the 8th digit of your VIN # XXXXX?

Customer: replied 8 years ago.

the car is a 1985 monte carlo ss, the 8th digit is a wanting to put a larger cam mostly to sound better and perform a little better. im not wanting to change heads, wanting to know the stock numbers of cam lift and duration....and also the most i can go in lift and duration without valve and piston problems. i believe the lifters are hydraulic flat tappet



humble tx

Expert:  phil replied 8 years ago.

The original cam was indeed a hydraulic flat tappet cam. It is a .404/.415 lift and 202/206 duration @ 50 with a 115 degree lobe seperation.


As for piston to valve clearance, there isnt a spec for maximum lift and duration of a motor, but if you are planning on keeping the car streetable there is no way you will be installing a cam that will cause valve to piston issues.



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