My '69 440 GTX vs My 2003 Mustang Cobra 4.6.

Cojohnso1

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So we ran the two street only cars. (Two years ago.) That on paper are very close. But performed much differently.

'69 GTX 440: a little higher (purple grind) perf cam than stock. Dual plane low rise eddy performer intake. 750 Holley stock exhaust. Approx 410 HP.

'03 Mustang Cobra Supercharged 4.6l. Stock. Approx 400 HP.

GTX A833 4-speed. 1st gear 2.66. Final gear 1.0 Dana rear 3.54:1. Rear tire height 28" on 15" rim.

Cobra 6 speed TI. 1st gear 2.66. Final gear 0.63:1 rear tire height 25.6" on 17" rim. Rear gear 3.55:1.

Both cars very similar dry weight at 3650 lbs.

Race was on a 4 mi closed highway section. (That I'm pretty sure not legal. But better than public access.) A 5-10 MPH 1st gear punch.

Cobra jumped out to and maintained 3 car length lead to 1/4mi end. GTX caught at about 3/4 mi. Cobra then had enough. GTX still pulling a little bit. Estimate speed 140 MPH.

The taller tires of GTX showed as expected. Especially thru the gears. I thought .63 gear would allow Cobra to hold better at top end. My friend driving said car was done. And a little spooky vibration beginning. So shut down first.

So in closing? The newer Cobra was quicker. But 440 was able to real it in. Driving both I suspected this would be the case. The 440 just takes more time to get into its optminal power band. But when it did? It was spitting mad chasing down the Cobra. The car is unlike my first '69 GTX of VERY simular build that I had many years ago. A bit slower thru the gears. But a MUCH better highway commando. Remarkably stable at high speed.



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Cojohnso1

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Change to a single plane and give it another rip.
Well. The road is not always available. Only after DOT is done with their testing. But intake is the first place to start. (Except pulling heads) The Cobra has a smaller supercharger pulley and belt upgrade (w chip) that still held Ford warranty. Supposed to kick HP up near 500. About $1200 upgrade. The Cobra stock shifter sucks. But they have an aftermarket replacement that addresses this well documented complaint. GTX? A whole lot that can be done with 440 and $1200? Head porting and intake with cam upgrade. That's about $1200? (Alot more work.) But could get it a 480 HP vs 480 HP?
 
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Cojohnso1

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Not looking to do any upgrades. There is a run on the these Cobras. A $7500 car just 3 years ago. Now going for $15k+ And I have posted this before. I'm very capable of screwing up something that doesn't need fixing? Lol. Either cars. If GTX is going faster? It will be with a different engine and build.
 

BeepBeepRR

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The supercharger is the difference. If the 440 was procharged or turbo it woulld be a world of difference. You just compared an apple to an orange. Its like putting your cobra up vs the TESLA Plaid model. That Electric car would eat the cobra alive. Torque right off the start and lots of it.
 
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hunt2elk

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Cool comparison. Maybe just me, but I'll take that GTX and stick it in my garage every single time over a newer model car.
 

padam

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I would say that if the GTX was reeling in the Cobra on the top end, it was close to or making more power. (Unless the Cobra was redlined.)
 

BeepBeepRR

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When I take the roadrunner out. And its not even my car. But I do have my own set of keys to it. I get thumbs ups every where I go. Every redlight People are taking pictures. If I drove a mustang the only people that would throw me a thumbs up have fanny packs and a man bun.
 

64fury74charger

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This side by side comparison shows how well mopars 50 year old build handles not only power but higher speed. Having driven several of the newer mud stains there seems to be vibration problems and floating above about 75 mph.
My Charger is smooth and stable at 130 and that’s with stock suspension.
 

Cojohnso1

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The supercharger is the difference. If the 440 was procharged or turbo it woulld be a world of difference. You just compared an apple to an orange. Its like putting your cobra up vs the TESLA Plaid model. That Electric car would eat the cobra alive. Torque right off the start and lots of it.
Totally agree. It was cubes vs boost. That Ford DOHC with its cute little Eaton roots type supercharger is a nice small V-8 package that was nicknamed the "Terminator." 10lbs of boost in stock trim. But in typical Ford fashion? They discontinued after a 3 year run. And of course it's not applicable to other engine platforms. I have never understood Ford thinking?
 
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64fury74charger

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Totally agree. It was cubes vs boost. That Ford DOHC with its cute little Eaton roots type supercharger is a nice small V-8 package that was nicknamed the "Terminator." 10lbs of boost in stock trim. But I typical Ford fashion? They discontinued after a 3 year run. And of course it's not applicable to other engine platforms. I have never understood Ford thinking?

Ford is still in the learning stages and not doing well. Too many people doing the same thing in different rooms! :rofl:
 

BeepBeepRR

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Ford is still in the learning stages and not doing well. Too many people doing the same thing in different rooms! :rofl:
Thats exactly why back in the late 80s early 90's I stayed away from the mustangs. Everyone had them and I mean EVERYONE. The others had Iroc Camaros. My I went by way of Japan with a street ported 12A Mazda Rx7. That little car would smoke most factory V8 cars with no issue.
 

64fury74charger

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Thats exactly why back in the late 80s early 90's I stayed away from the mustangs. Everyone had them and I mean EVERYONE. The others had Iroc Camaros. My I went by way of Japan with a street ported 12A Mazda Rx7. That little car would smoke most factory V8 cars with no issue.

Fun times, Some years ago I had an early Mazda Miata with a 5.0 and 5 speed from a munched mudstain and that car was flat out insane and a predator on the street. I had some friends that did nothing but fast rotary motors and they knew all the tricks. Those were fun times for sure.:thumbsup: :lol: :steering::thankyou: :luvplace: :rofl: :rofl:
 

Cojohnso1

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Thats exactly why back in the late 80s early 90's I stayed away from the mustangs. Everyone had them and I mean EVERYONE. The others had Iroc Camaros. My I went by way of Japan with a street ported 12A Mazda Rx7. That little car would smoke most factory V8 cars with no issue.
I just don't understand Ford's thinking? They have had winners before. (427, 351c ect..) But then they drop that line. After a short run. Remember folks questioning Chrysler when they dropped one of the most all time successful engines? The 225 slant 6? But that was at least a 20 year run. I think Ford fears any success? Something works well? And they then screw it up?
 

TTSaleen

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That is cool.
I have my 68 and a 2003 Mach 1 (it has a complete Terminator drivetrain swap - but was built/hopped-up).
Nice stable of cars you have!
Ryan
 

BeepBeepRR

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Fun times, Some years ago I had an early Mazda Miata with a 5.0 and 5 speed from a munched mudstain and that car was flat out insane and a predator on the street. I had some friends that did nothing but fast rotary motors and they knew all the tricks. Those were fun times for sure.:thumbsup: :lol: :steering::thankyou: :luvplace: :rofl: :rofl:
Thing was when I got the Rx7 it was ugly as hell. I was going to paint it that GEO storm green. But the guy who painted it ran out. But he had a half gallon of Ford motor blue. We painted it ford engine blue. Everyone knew who I was and what that car was capable of. I ended up blowing out the rear end smoking 30 feet of 2nd gear posi. I priced a rear end and at the time I didn't have the money. So I sold the car.
But I ended up buying 8 more after that. Most were parts cars. Only ever had 3 running and driving. But none were as fast as what I call the Smurf mobile.
 

Cojohnso1

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That is cool.
I have my 68 and a 2003 Mach 1 (it has a complete Terminator drivetrain swap - but was built/hopped-up).
Nice stable of cars you have!
Ryan
It is. And was fun comparing the performance with a classic muscle. I have parked both cars at our local pub's VERY small car show. The GTX still gathers more interest. But Mustang holds it's own. I acquired the Mustang more by default. I bought from an ex girlfriend who was unable to maintain. I'm massaging for my son to take over ownership. He has some wrench skills. (After dragging him along on some drag track efforts) But he and my other kids just don't have the car bug? If my dad had performance cars that need wrench and drive time needed? I would still be living in his basement? Lol. But to each their own.
 

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