Ford GT Question

[Removed user as requested]

Hello,

Have not posted in a while, been getting things organized here...

My 69 mach 1 mustang has been fun, but... decided to sell and use the money to work for me so that I can eventually do what you guys do... Restore a car, make it reliable with EFI, big brakes, nice new engine with good horsepower, electrics etc so it can be driven without worrying about something gonna blow or w/e because its still all 'old'. So for now its a be patient game and be smart with the means thus acquired.

If all goes well however, I may be in opportunity to get myself a GT. I have driven heaps of muscle cars now and I seriously wanna give a modern mid engine car a go.

The Ford GT is a small block Supercharged car 550HP or so.

Is that the only sort of engine that actually fits in a GT, or, like the GT40, you can get a big block in there? I would prefer car to be naturally aspirated than supercharged so I wonder.

Would a 550HP supercharged motor produce more torque than a N/A motor or would the N/A overall perform better at the same HP?

Thanks

[shmoov69]

Virtually any power adder engine will outperform a NA engine.... With equal drivability that is.

[vette427-sbc]

The GT doesnt really seem fitting of a big nasty N/A motor IMO...
I had the opportunity to drive a whipple'd one and believe me, you will love the boost

[Removed user as requested]

So how does the supercharge work?

I only ever owned N/A motors and why I like them, they got power from start to end... Turbos have lag, been in those things... Supercharge I never had experience with.

The GT claims 500 ft/lbs with 550 HP... far as I know a big block with 550HP would have over 600 ft/lbs making it 100+ more than the SC... or is that changeable via different SC or setup?

[Cobra 498]

I have a 2005 GT, I put a 4 liter Whipple on it, long tube headers and magnaflow mufflers and did not touch the internals, it made 862 HP at the wheels and is still very drivable
with that combination with twin turbos over a thousand is very easy. The Mod motors like boost and seem to live pretty well in that situation. The car is a little on the porky side though, 3400 lbs but it really puts power down well, has a super stiff chassis that responds to changing spring and bar rates. The motion ratio's are also very good almost .9 to 1 in the rear and about .8 to 1 in the front so shock damping is excellent. Braking is unreal because there is so much rear weight bias you get a lot more braking from the rear tires that any front engine car. The only assist is ABS, you are on your own for stability, traction control etc, it is the last super car that came without driver aids. Transaxle is a Recardo and is a very good unit from a durability standpoint. The downside of these cars is that collectors are bidding them up over 200k now and parts are hard to find and very expensive.
They made a little over 4000 cars and there are roughly 3000 now because people that can afford them can't necessarily drive them. There are some salvage cars out there but the repairs are very difficult to do and should not be undertaken by just anyone. Aero is very good as evidenced by the standing mile record that is held by a ford GT at 283 mph. These cars are very stable at high speeds and have excellent suspension geometry too, although it is a little conservative in the roll under steer department but that can be fixed. I think you could get one down to under 2900 lbs with a light normally aspirated powertrain so it would handle better but not have the grunt that lots of PSI brings. I was radar gunned at Willow Springs on the front straight at 174 mph which is pretty good for that relatively short straight, I did not hit turn 9 hard which shows how well they can accelerate.

[Matt@BOS]

If you ever get one, don't take the blower off. I'd wager that the 5.4 blown mod motor has a more useable power band than a big block making the same numbers. I have one in a 2012 GT500 and it just pulls from idle to redline seamlessly. It doesn't lag like a turbo car, or lug down low like a naturally aspirated engine with a cam. It simply makes power all the time.

Matt

[Removed user as requested]

Thanks for the replies. Spoke to whipple, pretty much have awesome SC's available with more Power/TQ than necessary.

How much does extra HP/Torque add to a time around a race track?

Top Gears track the GT is down at 1:21, with a whole bunch of everything including the Skylines infront. Just adding 200-300HP to the car, would how significantly change the 1:21, or could it actually get worse if nothing else is looked at?



Trying to keep it simple here as I am not looking into 'mods' anymore of insane customizations as previously wondered/talked about many months ago. Just throw a new blower, power increases, time changes how dramatically? Straight forward

[Cobra 498]

Thanks for the replies. Spoke to whipple, pretty much have awesome SC's available with more Power/TQ than necessary.

How much does extra HP/Torque add to a time around a race track?

Top Gears track the GT is down at 1:21, with a whole bunch of everything including the Skylines infront. Just adding 200-300HP to the car, would how significantly change the 1:21, or could it actually get worse if nothing else is looked at?

Trying to keep it simple here as I am not looking into 'mods' anymore of insane customizations as previously wondered/talked about many months ago. Just throw a new blower, power increases, time changes how dramatically? Straight forward

The car is way too soft in stock form I added Penske shocks, increased the spring rates and changed the tire brand and sizes which really helped. They put undersize front tires on to make the car under steer which really kills lap times. I went with 255-30-18 in place of 235's and put 345's on the rear, the Goodyears are garbage, Michelin, BF Goodrich, Hoosier or Bridgestones are all way better for grip. I also lowered the car 2" all around increased the length of the front splitter to 7" and added braces. I put skirts on to keep air flowing under the car to the diffuser and installed a GT1 wing at the rear. The car works very well now even in an autox, the biggest improvement was tires and springs. I would guess you could get about 3 seconds from tires springs and wheels. About 5 total with the aero stuff. I more than doubled spring rates and changed the toe curves slightly so I could get the car to turn in. The car felt lazy and unresponsive in stock form but people are still crashing them so I guess they needed to build in under steer. The ride is still good even with the high spring rates, about like a Porsche GT3 and the spring rates keep it off the ground even though it is lowered.

[Removed user as requested]

Thanks for that. I did wonder what size tyres would fit in back. Was hoping to be able to fit a 335, you obviously did. Would that fit without widening the body at back? I like Michelin tires, they have 335s available for 17" wheels. Would the 17" with 335s work out good or better with 18s... weight wise i thought the 17s would be the way to go. Everything you answered that i bad wondered but wasnt going to ask... still though... if all was left stock, and just the power was added 200-300hp from the whipple SC. What would that yield in return time wise?

Also in regards to buying one, is there any difference from the 2004-2006 model, more preferable, updates etc or identical in every way?

Can you post a picture of your 2005 GT?

[Cobra 498]

I would go with 18" wheels rather than 17 because of tire availability, you really have to be careful about front to rear rolling diameter ratios or the ABS will put the engine in limp home mode after 2-3 laps. I used 255's and 345's because the 255/345 rolling diameter ratios matched the stock tire ratio. I first used 265 and that gave the ABS system a false indication that the front tires were rotating slower than the rears said they should be which triggered the ABS warning. I looked into modifying the Bosch system and found that it was prohibitively expensive. Another alternative would be to make new tone wheels to "fool" the system so that you could use wider front tires that might be too tall. In the end I bought a new set of front tires that gave me the right rotating ratios. The abs expects to see a ratio of pulses front to rear that match the profile if different it thinks there is a failure. The 255's worked perfectly so I stopped at that point.

There is plenty of tire clearance on these cars especially at the rear. Just adding power alone will not do much for lap times unless you have some really long straights. These cars are just way too sloppy in stock form to really handle transitions well and they under steer badly when pushed I upped the rear wheel rate vs front wheel rate to get some low speed over steer then as the aero comes in the cars goes neutral at 100mph to slight under steer at really high speed (above 130). I am not sure about how to post a picture here but this is a youtube video that will give you an idea of what the car looks like. http://www.youtube.com/watch?v=RsQoE1T-aNs.

The GT's were only sold as 2005 and 2006, the 2006 model had an open front grill configuration to aid in cooling (a big problem with forced induction engines). I developed a pulsed water spray system that can run for about 20 minutes on 2 qts of distilled water. It cools the radiator and inter cooler and runs about as long as I can drive hard which isn't long at my advanced age. There may be some other differences but they are very minor and of no consequence to my knowledge.

[Removed user as requested]

The 345 tyres, they on 18" wheels? Cant find who does them. I have seen 335s.

[Dave B]

If you can get one, grab it! It's only a dream for most of us.

[Removed user as requested]

Thanks.

Dumb question... but... the GT body is not carbon fiber?

Does anyone make a Carbon body for them... or not yet... would there be any future plans as these cars become obsolete to make things like that considering they invented a CF body for the GT40?

[Cobra 498]

I went to 19x9.5 F and 19x12 rear wheels with Michelin PS2 265F and 345 R then switched to Hoosier 265x19 f and 345x19 rears. I started having trouble with the ABS light coming on after a few laps which switched the engine into a mode that would not go over 100 mph. I then got some 18x9.5 fronts and mounted 255x18 Hoosiers so that the ABS would be happy. I believe you can get Michelin Pilot Super Sports in these sizes. If I were to buy wheels again I would try 18x13 with 335's in place of the 19x12 with 345's but you still have to make sure that your revolutions per mile front and rear are the same percentage as the original Goodyears or you will have big ABS problems. The only alternative would be to buy a Bosch racing ABS like the Porsche guys do or maybe a MOTEC controller and dash where you could modify the signal put on the CAN bus by the ABS. The newer Michelin tires are way better than the PS2's which were not all that bad.

[Cobra 498]

Thanks.

Dumb question... but... the GT body is not carbon fiber?

Does anyone make a Carbon body for them... or not yet... would there be any future plans as these cars become obsolete to make things like that considering they invented a CF body for the GT40?

The car body is aluminum except for the hood but as I remember a team (not sponsored by Ford) built lots of carbon fiber parts for them including doors, fenders and rear body, that car was down to 2400 lbs with a normally aspirated engine. There was also a team operating in Europe that had lots of carbon fiber parts for their cars.

[REAL Bob Johnson]

How about something a little different? A 1970 mustang with a gt-ford motor and trans

[Bill Howell]

How about something a little different? A 1970 mustang with a gt-ford motor and trans

Very Nice Bob. Did you do this?

[REAL Bob Johnson]

Yes sir It's probably the best driving car i've built. Bill if you kno anyone might want it for sema let me know. It's that kind of car Thank's Real Bob

[Bill Howell]

Would owner be interested in driving it in the OUSCI???? Very cool looking piece. I will ask around.

[Bill Howell]

any pictures of how you did the interior?