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Mach 1 Change in late 03 and 04 Mach 1 heads ?

  • Thread starter Thread starter CanuckMustang
  • Start date Start date Feb 28, 2004
C

CanuckMustang

New Member
Jul 15, 2003
45
0
0
Toronto, Canada
Feb 28, 2004
#1
  • Feb 28, 2004
  • #1
I'm considering buying a late build date 03 Mach 1. Is there any truth that Ford improved the heads (i.e. grinded exhaust ports) late in the model year to improve performance? Supposedly the better heads have blue markings on them and flow noticeably better (as per a thread on Mach-1org web site).

I'd also like to know if the new exhaust systems on 04 models increased horsepower.

Anyone out there know the facts or have seen dynos that prove this?

I'd appreciate any help as I am looking to buy a new 03 or 04 Mach 1 right now.
 
S

Snakeeper

Member
Jan 1, 2003
46
0
6
Corona, Ca
Mar 1, 2004
#2
  • Mar 1, 2004
  • #2
CanuckMustang said:
I'm considering buying a late build date 03 Mach 1. Is there any truth that Ford improved the heads (i.e. grinded exhaust ports) late in the model year to improve performance? Supposedly the better heads have blue markings on them and flow noticeably better (as per a thread on Mach-1org web site).

I'd also like to know if the new exhaust systems on 04 models increased horsepower.

Anyone out there know the facts or have seen dynos that prove this?

I'd appreciate any help as I am looking to buy a new 03 or 04 Mach 1 right now.
Click to expand...
Nope! They are the same heads. I have an 03 and it has dynoed at 295rwhp and 308 torque SAE!
 
L

lamach1

New Member
Dec 21, 2003
16
0
0
Mar 1, 2004
#3
  • Mar 1, 2004
  • #3
CanuckMustang said:
I'm considering buying a late build date 03 Mach 1. Is there any truth that Ford improved the heads (i.e. grinded exhaust ports) late in the model year to improve performance? Supposedly the better heads have blue markings on them and flow noticeably better (as per a thread on Mach-1org web site).

I'd also like to know if the new exhaust systems on 04 models increased horsepower.

Anyone out there know the facts or have seen dynos that prove this?

I'd appreciate any help as I am looking to buy a new 03 or 04 Mach 1 right now.
Click to expand...
As far as I can tell, there is no difference. Early cars have dynoed as high as later cars. As far as the blue paint on the heads, it has been verified that some of the cars with the early build dates also have the blue paint.
 
C

CanuckMustang

New Member
Jul 15, 2003
45
0
0
Toronto, Canada
Mar 8, 2004
#4
  • Mar 8, 2004
  • #4
There must be a difference in the 04 Mach 1 power ratings. The highway fuel consumption is down 1 mpg on the 04 vs 03's indicating an improvement in efficiency. On the contrary the highway consumption is up 1 mpg on the 04 GT suggesting a loss of power.
 

TR03Mach1

Member
May 31, 2002
450
0
16
New Castle, Delaware USA
Mar 8, 2004
#5
  • Mar 8, 2004
  • #5
You'd be hard pressed to prove to me that there is a difference. I have a very early build 03 Mach 1 (Nov 8, 2002) and my engine has blue paint on the driver's side head, but not on the passenger side. I understand that the 04's have a six-brick cat system vs the 03's four-brick cats. I just had mine dyno'd and it's putting out more power than a lot of 04's. See sig.
 
7

760-MPH

Founding Member
May 9, 2002
432
0
0
Elkton, MD-Newark, DE
Mar 11, 2004
#6
  • Mar 11, 2004
  • #6
Snakeeper said:
Nope! They are the same heads. I have an 03 and it has dynoed at 295rwhp and 308 torque SAE!
Click to expand...


can i see your dyno please?
 
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