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Discussion Starter · #1 · (Edited)
In November 2012 my 01 Cobra had a catastrophic failure when my oil pump exploded. I found a donor car. A 2004 Mach 1 with 50k miles, I bought the entire motor and trans including the ecu, wiring, shifter and shakerhood for $4,200.

Before the install I wanted to research and learn everything I could about the 01 and 04 motors. After about 3 weeks of study I confirmed there are 5 main differences in the Mach 1 motor.

1. Mach 1 has a little better flowing lower intake.
2. has Terminator heads a little better flow
3. Do to the newer head design compression is up from 9.8 to 10.1
4. larger exhaust manifold ports.
5. smaller 186deg intake cams.

After countless number of articles and dissecting dynos I came to the belief that both motors produce about the exact same rwhp in a little different way. The Mach 1 does it by a little better engine flow and the Cobra does it with a little more aggressive intake cams.

The most populer cam mod for Mach 1 owners is to use the 96-98 cobra cams gaining 20 to 25 rwhp. But there is really no write up or info on the 01 cams. Until now!

When I first pulled my cams to install in the Mach 1 I found out that 99 and 01 Cobras have completely different cams.

99 cams (XR3E-6A270-AD) (XR3E-6A271-AD)
01 cams (YF3E 6A270 BB), (YF3E 6A271 BB)

Also most info on 99-01 cams is very confusing. I have heard from 196 to 200deg duration. Also no one seems to question “Why do they have different cams?”

Suprisingly I did find a motor that has 01 Cobra cams with specs.. The Australian Boss 260. But the only problem is the Boss 260 specs are in metric as follows.

BOSS 260
Intake CamshaftRH-(YF3E 6A270 BB) LH-(YF3E 6A271 BB)

Intake Opens @ 6Deg BTDC
Intake Closes @ 70Deg BTDC

Intake Opening:2.54mm Lift @ 30 Deg ATDC
Intake Closing:2.54mm Lift @ 30 Deg ABDC

Max. Lobe Lift =5.54064 mm @ 120 Deg ATDC {10mm at Valve##

Exhaust CamshaftRH-(YF3E 6A272 BB) LH-(YF3E 6A273 BB)

Exhaust Opens @ 54Deg BBDC
Exhaust Closes @ 16Deg ATDC

Valve Lift 2.54mmLift @ 17 Deg BBDC for Exhaust Opening
Valve Lift 2.54mmLift @ 23 Deg BTDC for Exhaust Closing

Max. Lobe Lift =5.55152 mm @ 110 Deg BTDC {10mm at Valve##

So I converted the numbers and this is what I got....

Intake: 256 [email protected]/.392 lift
Exhaust: 250 deg @.006/.393 lift

At 2.54mm lift = .1 inch
Intake: 180 [email protected]/.392 lift
Exhaust: 174 deg @.100/.393 lift

Now these numbers don’t tell you the exact specs @ .050lift, but they do tell 2 things.
1. The intake cam has a larger duration then the exhaust cam.
2. Its 6 degrees larger.

Now if we assume the exhaust cams are 196deg @ .050 lft like all the other 4.6 4v cams. Then the 2001 Cobra specs are as follows.

Intake: 202 [email protected]/.392 lift
Exhaust: 196 deg @.050/.393 lift

I also believe but can’t confirm yet that the 99 Cobra cams are a smaller duration then the 01, Maybe as low as 196. I think Ford used different cams in the 01 to make up for the "FIX" needed on the 99s making sure they were not overrated again.
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