500rwhp!?Waiting for the dyno sheet...
500rwhp 2003 Cobra!
- Thread starter 03DOHC
- Start date
I believe they mean tuning with the diablosport.
Any dyno sheet yet?
I was communicating closely through email with a DiabloSport engineer for the past month. They have been working feverishly on a chip for about three weeks now.
Attached is the latest email that I got from Johan, a Diablosport engineer:
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Alright, we just got back from the dyno with the SVT, this car had borla cat back and high flow cats, air filter, horn removed and we ended up putting a pulley on that. This gave us 497 rwhp SAE, I think this dyno might be a little loose, stock with exhaust it gave 411 so I would say it is 20hp off but that is still 477rwhp air fuels where perfect. We also put the rev at 7000.
The chip gave about 20rwhp over the whole powerband.
Thought you would like to know.
Sincerely
[email protected]
3500 NW Boca Raton Blvd. Suite 506
Boca Raton, FL 33431
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Horn removed is the silencer. Johan thinks that the dyno is inaccurate but it probably isn't. Stock with new exhaust got 411RWHP and we have already seen that many times (give or take a few HP). Mine made 382RWHP with only a K&N and snorkel removed. I can understand that these engineers can't believe the power that can be unleashed from our 03's but it's true. I don't doubt for a minute that those dyno figures are accurate.
What I like is that he upped the rev limiter to 7K!! DAMN!! I'm jealous...my SuperChip doesn't do that. I'm going back to the dyno early next week to see how the ECC adapted to my program and what the AFR's look like. We are expecting them to be much richer; that's what the comptuer will do with changed values.
Within the next few months; 500 RWHP is going to be commonplace for those who have a big enough "wee-wee" to modify their Cobras.
I am also scheduled for mod's next week: full Kenny Brown chassis stiffening and 4.10's. My chip will be re-programmed to calibrate it to the new gears so the speedo is accurate.
Has anyone else thought about upping the ring and pinion? An upgrade to 4.10's should be worth a half second at the track. I'll let you all know.
Attached is the latest email that I got from Johan, a Diablosport engineer:
-----------------------------------------------------------------------------------
Alright, we just got back from the dyno with the SVT, this car had borla cat back and high flow cats, air filter, horn removed and we ended up putting a pulley on that. This gave us 497 rwhp SAE, I think this dyno might be a little loose, stock with exhaust it gave 411 so I would say it is 20hp off but that is still 477rwhp air fuels where perfect. We also put the rev at 7000.
The chip gave about 20rwhp over the whole powerband.
Thought you would like to know.
Sincerely
[email protected]
3500 NW Boca Raton Blvd. Suite 506
Boca Raton, FL 33431
----------------------------------------------------------------------------------
Horn removed is the silencer. Johan thinks that the dyno is inaccurate but it probably isn't. Stock with new exhaust got 411RWHP and we have already seen that many times (give or take a few HP). Mine made 382RWHP with only a K&N and snorkel removed. I can understand that these engineers can't believe the power that can be unleashed from our 03's but it's true. I don't doubt for a minute that those dyno figures are accurate.
What I like is that he upped the rev limiter to 7K!! DAMN!! I'm jealous...my SuperChip doesn't do that. I'm going back to the dyno early next week to see how the ECC adapted to my program and what the AFR's look like. We are expecting them to be much richer; that's what the comptuer will do with changed values.
Within the next few months; 500 RWHP is going to be commonplace for those who have a big enough "wee-wee" to modify their Cobras.
I am also scheduled for mod's next week: full Kenny Brown chassis stiffening and 4.10's. My chip will be re-programmed to calibrate it to the new gears so the speedo is accurate.
Has anyone else thought about upping the ring and pinion? An upgrade to 4.10's should be worth a half second at the track. I'll let you all know.
500hp
Did they try any headers?? Short or long...
Did they try any headers?? Short or long...
I don't think 4.10's will give you that much of an advantage in the 1/4. Maybe 1-2 tenth's. JMO.
1 or 2 tenths? Naah...I'll have to disagree with you on that. Not with a 475 HP car. Have you ever done a ring and pinion upgrade? There is not a more VIOLENT acceleration upgrade that you can do. Granted, you gotta know how to pedal the sh*t out of the gas and clutch; since the car will want to walk sideways all the way through third. But outta the hole you can side-step the clutch @ 2 grand and it'll jump hard.
But MPH and ET will improve DRASTICALLY. I have had mustangs with 3.55's, 3.73's and 4.10's. And the difference between 3.55's and 4.10's is like black and white. The 03's want to tach out to make their big power. The 4.10's will give them just that. And with that 2nd over-drive that the T-56 gives us, the 4.10's should be ideal for street/strip comfort.
And lower gears (numerically higher) are HUGE FUN on the street. Nothing like that WHIPLASH snap of the throttle that 4.10's give you.
But we can BS about it all day...it doesn't matter. The numbers will speak for themselves. My only concern is bouncing off of the limiter in fourth up-stairs at the track. You don't want to see fifth when racing. It won't matter...I'll be putting a much taller drag-radial tire on it eventually anyway. That'll keep it off the limiter up top.
Stand-by; I'll be posting results.
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I had 4.30's in my '97. I've since removed them in case I have to trade in my car for the '03. Yes, there was a big difference in how the '97 responded, however, it's torque curve looks nothing like the 2003 Cobra's does.
'97 Cobra torque curve= ^
2003 Cobra tq curve= ----
Anyway, JMO.
'97 Cobra torque curve= ^
2003 Cobra tq curve= ----
Anyway, JMO.
Do me a favor, please run the car at the track with the stock gears, then go back with the 4.10's with no other changes. Unless you are running slicks, you will not be able to do any better with the 4.10's Flame away if you must, but I've seen it time and time again. All you are doing is moving the torque to an area where you can't use it. Now if you slap on some 28x9 slicks, look out, you'll get your .5 seconds.
And yes, I do have experience with changing rear end gears. My 351 windsor powered '82 GT had 3.08's, 3.73's,4.10's and ended up with 4.56's. It ran low 11's at mid 120's (on said MT 28 x9's) with the 4.56's, I'd say it had 450-500 HP. Through the years of modifying it, it would never go faster with a gear change alone on street tires or the street slicks of the day (Drag radials hadn't been invented yet, ;-)). it took slicks to get the new torque to the ground.
Put it another way, if you go to a decently prepped track, with the stock gears you should be able to get mid 1.9's on the f1's, and 1.8's or possibly1.7's on DR's. When you switch to the 4.10's those numbers won't change for any but the luckiest of launches, there is no way your gonna go .5 faster with the same 60 ft and the same hp.
Please go to the track and prove me wrong, cause the higher gears do feel great on the street...
JT
I disagree. Although 3.55 sounds like decent rear end ratio, add the T56's 2.66 first gear, and you have the equivalent of a 3.27 rear with a standard .9-3.0 trans ratio. That means the 03' has almost the same final drive ratio in first gear, as say, a 98 cobra. And i know 98 cobras benefitted GREATLY from a 4.10 swap. Granted, yes, it will take some serious skill to keep you stuck to the pavement, but , the benefit is definatley there. 60 fts may not change much with a 4.10 swap, but ill bet your 1/8th miles times will improve. The goal is to be almost peaked in 4th going thru the traps. To do that with the stock gears, would take a butt load of hp. When i get the vibration gets fixed on my 03, 4.10's are going in for sure!!!
You don't run the entire 1/4 in first gear.
Anyway, have fun. Night all.
so they didn't quite make 500hp.. but 499hp is damn close:burnout:
No doubt, short times won't improve on the F-1's. Nothing will make the 60' times improve with the F-1's and the stiff suspension in the 03. They say that every tenth down low is worth two tenths up top. I believe that is close to true.
But the 1/4 mile is much longer than the first 60'. Gears will greatly improve mid track and up top. There is NO WAY 1/4 mile times and MPH won't improve greatly with a 4.10 upgrade...even on stock tires. Granted it's going to take a seriously light touch and some skills to get the car out of the hole in 2 flat with gears. But it definately can be done.
I know the torque curve is flat. It's not about the torque curve; it's about RPMs.
Basically, gears make a car tach quicker...MUCH quicker. Our cars wake up when they tach above 5K. Recovery time between shifts will cut down 800%. You'll go through the traps in fourth at 6500-6,800 instead of 5,000. No ET/MPH improvement? RUBBISH!!! In a pig's eye!!
;-)
Don't misunderstand me! I love these debates and respect my fellow SVT'ers. Just having fun...As for the gears...just wait and see.
But the 1/4 mile is much longer than the first 60'. Gears will greatly improve mid track and up top. There is NO WAY 1/4 mile times and MPH won't improve greatly with a 4.10 upgrade...even on stock tires. Granted it's going to take a seriously light touch and some skills to get the car out of the hole in 2 flat with gears. But it definately can be done.
I know the torque curve is flat. It's not about the torque curve; it's about RPMs.
I have no idea where you are coming from with that one. Mabye you know something I don't. You're not moving or re-shaping the torque curve. You are making the car get through the curve faster. Put gears on the car and put it on the dyno...the torque curve won't change. It'll still reach maximum torque at 3200 RPMs (or whatever). Lower gears (numerically higher) mean that the wheels complete one revolution per more drive shaft revolution. For example, if the drive shaft must revolve three full times to get the tires to revolve one full time with 3.55's, then 4.10's will make the drive shaft require 5 full revolutions in order to get the tires to revolve once. This all gives the car more leverage to rotate wheels. It has nothign to do with torque curve. We are not talking about porting heads or changing intakes here. Those mods modify the torque curve. Gears up the bar on RPM usage...they don't change the curve.
Basically, gears make a car tach quicker...MUCH quicker. Our cars wake up when they tach above 5K. Recovery time between shifts will cut down 800%. You'll go through the traps in fourth at 6500-6,800 instead of 5,000. No ET/MPH improvement? RUBBISH!!! In a pig's eye!!
;-)
Don't misunderstand me! I love these debates and respect my fellow SVT'ers. Just having fun...As for the gears...just wait and see.
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- Jun 27, 2002
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Im with this guy. You guys are used to the Centrifugal way of thinking. Roots cars do BETTER hanging around in there sweet spot longer. And Way up in the RPM range is not a roots blown cars sweet spot. Now you may gain some ET with the gear swap. But I dont see it being more than .1 -.2. All this goes out the window if you run slicks.
Sweet spot is an abstract idea. It's relative to one's likes. The sweet spot for you might be the snooze spot for me. My sweet spot is mid to low 11's.
And gears don't make the car lose it's docile aspects. You still have a part-throttle. It can still get groceries. Gears do not change the powerband nor do they change the behavior of the blower - roots or otherwise. They simply change the rate of acceleration.
There's nothing that an 03 Cobra with 3.55's can do that an 03 with 4.10's can't (except cruize at 80 MPH @ 2500 RPMs...it will be more like 3,000 RPMs).
But an 03 with 4.10's will walk away from an 03 with 3.55's. I'll go to the mats on that one.
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- Jun 27, 2002
- Messages
- 5
I understand what you mean. really I do. But the Torque curve on the 03 Cobras start falling after about 4500, Seems like you would want to stay in that range just a little longer. INtsead of flying right out of it with 4.10`s.
This is a nice, fun debate.
Sorry, I meant the torque of the tires vs the track, which changes with each gear. You are adding more overall reduction in low gear, so now you have more torque (at the rear wheels) in first gear, so unless you currently don't have enough torque in low gear to brake the wheels loose (like you wouldn't with slicks) you are adding torque that can't be used. With 4.10's you can spin the rear tires "easier", so what? As for the rest of the track the gear change is meaningless. Look at it like this. with the stock rear 1st gear is good to x mph. If you switch to 4.10's you will hit redline at a lower speed in first ( .86 of the speed you where going before at redline, or .86x mph). Now you shift to second, and of course you have more gear in second than you used to have in second, but... you have less gear from .86x mph to x mph in second with the 4.10's, than you had in first with the 3.55. This is repeated for each gear. So you added more multiplication at some speeds and left yourself with less at others. I know you can make the argument that on average you have more multiplication, but I think if you could figure out how to "factor out" the extra multiplication in first you couldn't use because of street tires, it would be a wash.
And, don't forget what 4.10's will do to your 1-2 shift. With the 3.55's, I can generally shift 1-2 as hard as possible with little or no wheelspin (and no lost et). I doubt this would be true with 4.10's. So now with 4.10's we add more torque at the starting line to overpower the tires more than we could before, then we have to take an easy 1-2 shift so as not to completely lite up the tires again, strike 2 against a better et.
Strike 3: as I pointed out earlier, the shifts obviously happen "sooner". You have noticed how things that happen close to the starting line are much more critical than things that happen at the end of the track. As you pointed out, some people claim .1 of 60 ft is worth .2 of et. Well now you are moving each shift, each momentary pause in power to the track, earlier, to a slighlty more critical place on the track. So, you need to shift like a trained mongoose, while of course not breaking the wheels lose with all your new rear wheel torque.
When all is said and done, I believe that money spent on gears would be better spent on more HP, if better ET's on street tires or drag radials is your goal. Now if all you want is the car to "feel" zippier on the street, or you are going to use slicks, it is money well spent.
JT
Sorry, I meant the torque of the tires vs the track, which changes with each gear. You are adding more overall reduction in low gear, so now you have more torque (at the rear wheels) in first gear, so unless you currently don't have enough torque in low gear to brake the wheels loose (like you wouldn't with slicks) you are adding torque that can't be used. With 4.10's you can spin the rear tires "easier", so what? As for the rest of the track the gear change is meaningless. Look at it like this. with the stock rear 1st gear is good to x mph. If you switch to 4.10's you will hit redline at a lower speed in first ( .86 of the speed you where going before at redline, or .86x mph). Now you shift to second, and of course you have more gear in second than you used to have in second, but... you have less gear from .86x mph to x mph in second with the 4.10's, than you had in first with the 3.55. This is repeated for each gear. So you added more multiplication at some speeds and left yourself with less at others. I know you can make the argument that on average you have more multiplication, but I think if you could figure out how to "factor out" the extra multiplication in first you couldn't use because of street tires, it would be a wash.
And, don't forget what 4.10's will do to your 1-2 shift. With the 3.55's, I can generally shift 1-2 as hard as possible with little or no wheelspin (and no lost et). I doubt this would be true with 4.10's. So now with 4.10's we add more torque at the starting line to overpower the tires more than we could before, then we have to take an easy 1-2 shift so as not to completely lite up the tires again, strike 2 against a better et.
Strike 3: as I pointed out earlier, the shifts obviously happen "sooner". You have noticed how things that happen close to the starting line are much more critical than things that happen at the end of the track. As you pointed out, some people claim .1 of 60 ft is worth .2 of et. Well now you are moving each shift, each momentary pause in power to the track, earlier, to a slighlty more critical place on the track. So, you need to shift like a trained mongoose, while of course not breaking the wheels lose with all your new rear wheel torque.
When all is said and done, I believe that money spent on gears would be better spent on more HP, if better ET's on street tires or drag radials is your goal. Now if all you want is the car to "feel" zippier on the street, or you are going to use slicks, it is money well spent.
JT
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