XJR vs 2003-2004 Mustang Cobra power gains
#1
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So I've noticed that both cars have the same M112 supercharger. Aside the .6L (.4l for 2004+) more in displacement what makes that car respond better to power mods like pulley swaps?
I've read here that our blowers are already spun pretty fast and almost borderline, with more displacement I'd imagine it would take even more air to make power.
I've read here that our blowers are already spun pretty fast and almost borderline, with more displacement I'd imagine it would take even more air to make power.
#2
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My son has the 2003 SVT cobra, they have to tune the ECU every time they do a upgrade of some sort, they do it with some kind of module they tune, then down load into the ECU. If they go with the Kenne bell twin scerw they are almost up to 800whp and the same with the torque. My sons pushing 600 still using the M112 with a steiger snakebite port and re-gear.
#3
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My son has the 2003 SVT cobra, they have to tune the ECU every time they do a upgrade of some sort, they do it with some kind of module they tune, then down load into the ECU. If they go with the Kenne bell twin scerw they are almost up to 800whp and the same with the torque. My sons pushing 600 still using the M112 with a steiger snakebite port and re-gear.
Prove it. at the crank on a 30 degree day with nitrous MAYBE.
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#7
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adam, any ECU-controlled car needs a tune (modification to the ECU fuel and VE tables) in order to run significant power modifications. Your question as to why jags don't need tunes is probably best answered by the number of Jags that are modified for significant power gains. Almost none, compared to supercharged Mustangs. Why don't they need tunes? Because a stock ECU can accommodate little 5-10 HP gains with the stock maps.
You can't just throw a pulley at an S/C and expect exponential power gains. Any substantial increase in air charge must be matched by larger injectors, fuel rail, fuel delivery, spark, etc. etc. etc.
You can't just throw a pulley at an S/C and expect exponential power gains. Any substantial increase in air charge must be matched by larger injectors, fuel rail, fuel delivery, spark, etc. etc. etc.
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#8
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There is also a shortage of people out there who can work with the computer. There is ALOT of power left on the table in these cars. My previous set up which was ported blower (M112), Water/Meth, Pulleys, Eurotek Tune (Garbage), Custom Intake, low temp thermostat made 379rwhp on a dynojet. My new setup with be closer to 700. Lots of stuff coming out of Buckhead Imports for our cars and the power gains will be well worth the money.
#9
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I still haven't tuned my car, so am very pleased with the stock tune as it allows some good stretching...
Nevertheless, the perfect setup is the one where the tune is based upon the current mods one has. Maybe once I settle on the mods, I am going to fine tune it all on a dyno, that’s the only way, but also expensive. Not sure why there isn't so much available in the US, over here there are a couple of people that know what they are doing, and also are capable of adjusting our ECUs.
The shaper you tune, the less room you have to adjust again with other mods (unless you retune again), and the more risk you take on the engine, so somewhere one needs to draw a line imho, and the best tune doesn’t have to be the one that makes the most power imho.
@thunderkitten,
700 rwhp is pretty pretentious, that requires some serious adjustments to achieve and make it reliable also. Or are you going to use tricks like nos? If I may borrow your words, “Prove it”
Nevertheless, the perfect setup is the one where the tune is based upon the current mods one has. Maybe once I settle on the mods, I am going to fine tune it all on a dyno, that’s the only way, but also expensive. Not sure why there isn't so much available in the US, over here there are a couple of people that know what they are doing, and also are capable of adjusting our ECUs.
The shaper you tune, the less room you have to adjust again with other mods (unless you retune again), and the more risk you take on the engine, so somewhere one needs to draw a line imho, and the best tune doesn’t have to be the one that makes the most power imho.
@thunderkitten,
700 rwhp is pretty pretentious, that requires some serious adjustments to achieve and make it reliable also. Or are you going to use tricks like nos? If I may borrow your words, “Prove it”
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#13
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Lol @ U guys getting into a intercontinental cat fight![Wink](https://www.jaguarforums.com/forum/images/smilies/wink.gif)
I'm surprised no one offers tuning by data-logging, but than the ECU might not be flash-able through the OBD. In the Porsche world this is a very common option, where the tuner designs a basic/conservative tune based on your upgrades and than fine tunes it based on the datalogs you sent up after driving the car through a few cycles.
Anyway, as you guys can probably see, going with the 4.2 that just arrived I'm trying to set myself up for more mods in the future. I really appreciate the info that you guys put out there already as far as the info pertaining to swaps and upgrades. I'm really curious as to what else you guys have done in supporting mods?
Seems like you guys are putting out some serious power looking at your claims, have you upgraded the trans or is it holding up? How about fuel and ignition? I know some of you upgraded the superchargers, I didn't see too many pics as far as the setups, are you guys keeping that secret or willing to share?
Thanks,
Adam
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I'm surprised no one offers tuning by data-logging, but than the ECU might not be flash-able through the OBD. In the Porsche world this is a very common option, where the tuner designs a basic/conservative tune based on your upgrades and than fine tunes it based on the datalogs you sent up after driving the car through a few cycles.
Anyway, as you guys can probably see, going with the 4.2 that just arrived I'm trying to set myself up for more mods in the future. I really appreciate the info that you guys put out there already as far as the info pertaining to swaps and upgrades. I'm really curious as to what else you guys have done in supporting mods?
Seems like you guys are putting out some serious power looking at your claims, have you upgraded the trans or is it holding up? How about fuel and ignition? I know some of you upgraded the superchargers, I didn't see too many pics as far as the setups, are you guys keeping that secret or willing to share?
Thanks,
Adam
#14
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Need to be careful for copycats, Thunderkitten has already all my info gathered in different ways, yet doesn't let anything know on what he is doing, what a kitty.
Anyway TK, 700 bhp is still about 580 rwhp, and reaching that without "cheating", so no nos, water/meth, octane boosters/race fuel, would still be high imho. To get there I would need at least higher octane fuel.
But if I count some of the figures mentioned by your business partner of mods that I don't have, it might be achievable on my car, i.e. just the porting alone of the heads where like 40 to 80 hp (with a claim that those figures are modest), then a super tune and bang I would be at 600rwhp, and then I would still have stock headers and exhaust, so even more room. Don't get me wrong it would be great if the figures are true though...
So, chop chop kitty, get your car on the road and prove your claims.
Anyway TK, 700 bhp is still about 580 rwhp, and reaching that without "cheating", so no nos, water/meth, octane boosters/race fuel, would still be high imho. To get there I would need at least higher octane fuel.
But if I count some of the figures mentioned by your business partner of mods that I don't have, it might be achievable on my car, i.e. just the porting alone of the heads where like 40 to 80 hp (with a claim that those figures are modest), then a super tune and bang I would be at 600rwhp, and then I would still have stock headers and exhaust, so even more room. Don't get me wrong it would be great if the figures are true though...
So, chop chop kitty, get your car on the road and prove your claims.
#15
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Need to be careful for copycats, Thunderkitten has already all my info gathered in different ways, yet doesn't let anything know on what he is doing, what a kitty.
Anyway TK, 700 bhp is still about 580 rwhp, and reaching that without "cheating", so no nos, water/meth, octane boosters/race fuel, would still be high imho. To get there I would need at least higher octane fuel.
But if I count some of the figures mentioned by your business partner of mods that I don't have, it might be achievable on my car, i.e. just the porting alone of the heads where like 40 to 80 hp (with a claim that those figures are modest), then a super tune and bang I would be at 600rwhp, and then I would still have stock headers and exhaust, so even more room. Don't get me wrong it would be great if the figures are true though...
So, chop chop kitty, get your car on the road and prove your claims.
Anyway TK, 700 bhp is still about 580 rwhp, and reaching that without "cheating", so no nos, water/meth, octane boosters/race fuel, would still be high imho. To get there I would need at least higher octane fuel.
But if I count some of the figures mentioned by your business partner of mods that I don't have, it might be achievable on my car, i.e. just the porting alone of the heads where like 40 to 80 hp (with a claim that those figures are modest), then a super tune and bang I would be at 600rwhp, and then I would still have stock headers and exhaust, so even more room. Don't get me wrong it would be great if the figures are true though...
So, chop chop kitty, get your car on the road and prove your claims.
#16
#17
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Here are a couple of photos of the Twin Screw installed on my car. This is the car "Thunderkitten" is more concerned about. You will note he seems to always mention all other cars except this one as it is only 50 miles from him. The reason being he already knows the "Thunderkitten" is no match. If anyone has questions regarding Andre's Twin Screw it is everything he promises & more.
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#19
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BIP quoted 50% with the list of mods,
"We would like to see a 50% + increase in power which should be a easy task to accomplish".
-Performance heads, ported, polished with valve job
-Camshafts
-High strength valve springs
-Headers with down pipes
-Cooling system
-4.0L Supercharger kit
-Torque converter
-TCU flash upgrades
-Pistons
-Maf upgrades
-Throttle body upgrades
-Intake kits
With TC's car doing 340/380, they're aiming for 510/580. The output of 625-650 is 115/140 over their base claim, 45/70 over peak. How do you find these extra rwhp on the bench? By building a $20,000 plus engine, not skimping on using anything secondhand, custom made all the way.
Or, N2O.
"We would like to see a 50% + increase in power which should be a easy task to accomplish".
-Performance heads, ported, polished with valve job
-Camshafts
-High strength valve springs
-Headers with down pipes
-Cooling system
-4.0L Supercharger kit
-Torque converter
-TCU flash upgrades
-Pistons
-Maf upgrades
-Throttle body upgrades
-Intake kits
With TC's car doing 340/380, they're aiming for 510/580. The output of 625-650 is 115/140 over their base claim, 45/70 over peak. How do you find these extra rwhp on the bench? By building a $20,000 plus engine, not skimping on using anything secondhand, custom made all the way.
Or, N2O.
Last edited by Sean B; 09-08-2011 at 03:13 PM.
#20
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![](http://i171.photobucket.com/albums/u284/pattyjag/XKR/grille005.jpg)
![](http://i171.photobucket.com/albums/u284/pattyjag/XKR/grille004.jpg)
Here are a couple of photos of the Twin Screw installed on my car. This is the car "Thunderkitten" is more concerned about. You will note he seems to always mention all other cars except this one as it is only 50 miles from him. The reason being he already knows the "Thunderkitten" is no match. If anyone has questions regarding Andre's Twin Screw it is everything he promises & more.
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