Any of you guys see the GT500 article in the Feb issue of 5.0 Mustang & Super Fords? (My apologies if this is a repost or old news.)
Transmission/Gearing/Clutch:
First gear is 2.97:1 (vs. 2.66 on the ’03 and ‘04s). Rear-end ratio is 3.31 (vs 3.55 on the ’03). So overall gear ratio in 1st is 9.831 (vs 9.443 on the ’03). Also, from what I could gather from the article, 6th is the same ratio as ’03 (0.63:1). Clutch is a double-disk unit (215 mm = 8.44 in) sourced from Valeo. (Smaller diameter reduces polar moment of mass inertia so less inertial loss during acceleration.)
Engine:
Same deal on the block (wet-sumped 5.4L iron block). Static compression ratio is 8.4:1 (same as Ford GT, but vs. 8.5:1 on the ’03 Cobras.) Ford GT crank. Mahle connecting rods which the engineers claim are on par w/ the Manleys in the ‘03s, but less expensive. Heads are directly from the GT, including cams, valves, springs and ports and even have the same part number! (I know at one point there was speculation the cams might not be the same.) Redline is 6,000 rpm (we knew that) and fuel shut off is 6,250.
Blower:
Not too much new. Eaton M122H (H for hybrid…revised 5th-gen blower) Roots-style blower will be used. It has redesigned rotor and port design, but they don’t go into any details. They (Eaton) claim 15% improvement in adiabatic efficiency over the M112. (They don’t say if this 15% is an absolute or relative increase in AE, but it either way it means cooler outlet temps and lower drive power for a given mass-air flow rate and boost pressure.) Reportedly, a newly patented 6th generation blower will be out in 2008, but no mention of size(s). This has revised rotor pitch spacing. And as posted elsewhere, they did say/admit that Lysholm couldn’t provide the 40/day volumes that production would deman. Craig Sell was quoted as saying, “turbo efficiency from a Roots blower.” (Uhm…don’t think so. A turbo doesn’t have the mechanical drive power required by a Roots. As we all know, it’s driven by the heat energy in the exhaust gases which would otherwise be wasted. Yes yes yes…there is a back pressure penalty.)
Weight:
No real news…3850 lbs with F/R distribution of 57/43. (Oink). With 10 gals of fuel and driver(s?) it weighed in at 4155!
Suspension:
Stock Mustang GT K-member. Revised bushings, spring rates and shock rates. Same crap about the lack of IRS. (I have driven an ’05 GT and I must admit I was impressed with the solid.) The authors said they experienced no wheel hop with standing starts. They also said they felt it was better (handling-wise) over bumps and in turns than the IRS on the ’03.
Brakes:
14” front disks with 4-caliper Brembo pinchers. Rears are stock Mustang GT, but different pads.
Tires:
285/40ZR18 rear and 255/45ZR18 front GY Eagle supercar.
P.S. The issue also has a nice article on Mike Palugi’s twin-turbo ’03. rwHP/TQ = 811/717 at 22 psi. Niiice!
Transmission/Gearing/Clutch:
First gear is 2.97:1 (vs. 2.66 on the ’03 and ‘04s). Rear-end ratio is 3.31 (vs 3.55 on the ’03). So overall gear ratio in 1st is 9.831 (vs 9.443 on the ’03). Also, from what I could gather from the article, 6th is the same ratio as ’03 (0.63:1). Clutch is a double-disk unit (215 mm = 8.44 in) sourced from Valeo. (Smaller diameter reduces polar moment of mass inertia so less inertial loss during acceleration.)
Engine:
Same deal on the block (wet-sumped 5.4L iron block). Static compression ratio is 8.4:1 (same as Ford GT, but vs. 8.5:1 on the ’03 Cobras.) Ford GT crank. Mahle connecting rods which the engineers claim are on par w/ the Manleys in the ‘03s, but less expensive. Heads are directly from the GT, including cams, valves, springs and ports and even have the same part number! (I know at one point there was speculation the cams might not be the same.) Redline is 6,000 rpm (we knew that) and fuel shut off is 6,250.
Blower:
Not too much new. Eaton M122H (H for hybrid…revised 5th-gen blower) Roots-style blower will be used. It has redesigned rotor and port design, but they don’t go into any details. They (Eaton) claim 15% improvement in adiabatic efficiency over the M112. (They don’t say if this 15% is an absolute or relative increase in AE, but it either way it means cooler outlet temps and lower drive power for a given mass-air flow rate and boost pressure.) Reportedly, a newly patented 6th generation blower will be out in 2008, but no mention of size(s). This has revised rotor pitch spacing. And as posted elsewhere, they did say/admit that Lysholm couldn’t provide the 40/day volumes that production would deman. Craig Sell was quoted as saying, “turbo efficiency from a Roots blower.” (Uhm…don’t think so. A turbo doesn’t have the mechanical drive power required by a Roots. As we all know, it’s driven by the heat energy in the exhaust gases which would otherwise be wasted. Yes yes yes…there is a back pressure penalty.)
Weight:
No real news…3850 lbs with F/R distribution of 57/43. (Oink). With 10 gals of fuel and driver(s?) it weighed in at 4155!
Suspension:
Stock Mustang GT K-member. Revised bushings, spring rates and shock rates. Same crap about the lack of IRS. (I have driven an ’05 GT and I must admit I was impressed with the solid.) The authors said they experienced no wheel hop with standing starts. They also said they felt it was better (handling-wise) over bumps and in turns than the IRS on the ’03.
Brakes:
14” front disks with 4-caliper Brembo pinchers. Rears are stock Mustang GT, but different pads.
Tires:
285/40ZR18 rear and 255/45ZR18 front GY Eagle supercar.
P.S. The issue also has a nice article on Mike Palugi’s twin-turbo ’03. rwHP/TQ = 811/717 at 22 psi. Niiice!
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