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[88 dippy]

ok there has been a lot of talk so i looked in my 1988 factory manual

Stock Hydrolic roller cam
Cam lift (int) .2489"
Cam lift (exh) .2669"
Valve lift (int) .373"
Valve lift (exh) .400"
Duration at .050"  (int) 204
Duration at .050"  (exh) 211
Lobe seperation 109

stock Hydrolic Flat tappet cam
Cam lift (int) .2489"
Cam lift (exh) .2669"
Valve lift (int) .373"
Valve lift (exh) .400"
Duration at .050"  (int) 204
Duration at .050"  (exh) 211
Lobe seperation 109

hope this helps the first is the civilian cam the second the cop car cam

[Dippy.org]

[patrickgrossman]

don't think all that info is right....

the flat tappet cop cam is 240/248 advertised duration.  the roller cam is 240/240 advertised.

[Reggie]

don't think all that info is right....
the flat tappet cop cam is 240/248 advertised duration.  the roller cam is 240/240 advertised.

I agree. 
From The Library - Cop Cars:

Lubrite treated camshaft. 4bbl and 2BBL flat tappet and roller versions usually had .373"intake/.400" exhaust lift with 240/240 advertised duration. Specifications were the same as the civilian versions.

- RR

[88 dippy]

i got the specs straight from the 1988 RWD shop manual

i will double check though but using engine anylizer it looks right for the HP and TQ with the 240/240 it has to low of TQ

[Reggie]

It doesn't sound right.  240* duration @ .050 is in race cam territory.   My 1987 FSM list the cam specs as:
204*/211* duration @.050" and 240*/248* advertised duration. Lift at valve = 0.373"/0.400" and cam lift = 0.249"/0.267" - RR

[88 dippy]

ok i am an idiot the cam timing for both are the same

intake opens (BTC) 10*
intake closes (ABC) 50*
exhaust opens (BBC) 52*
exhuast closes (ATC) 16*
Valve over lap 26*
intake valve duration 240*
exhuast valve duration 248*

also the lobe seperation is the same at 109*



so after looking through the manual and finding out the duration is at the seat and not at .050" i think i got it


the lift is also the same as well   
int valve lift .373"
exhuast valve lift .400"

[IronBrick]

Seat to Seat duration is ALWAYS more than 0.050 Duration - and Roller Cam duration (seat to seat) cannot be compared directly to Flat Tappet cam duration.

[88 dippy]

then what would the flat tappet be @ .050" they give all specs as the roller and then change it if the flat tppet cop car cam is diffrent

[Reggie]

then what would the flat tappet be @ .050" they give all specs as the roller and then change it if the flat tppet cop car cam is diffrent

With both of those wimpy cams, the difference in duration @.050" between the roller and the flat tappet is probably insignificant. - RR

[88 dippy]

ok