610 rwhp GT500 vs 630 rwhp 03/04 Cobra

[littlejohn]

Mods are in my sig, however I found three bad plugs a week after the dyno. It's been wet up here in Alberta, Canada, so far this spring/summer. This is the first good race I've had this year.

Friend's got an 03/04 Cobra, that has a 2.3 whipple, stage 3 crower cams, full exhaust w/ headers, 3.73's, and has dynoed at 630 rwhp std last fall.

I dynoed 611 rwhp std at the same shop, a month ago, with possibly a bad plug or three. The plugs were I found through some research that iridium plugs do not have to be gapped as tight, as the plugs will 'quench', and too much heat will go into the ground electrode(the elbow), and eventually start burning it off. Two of my plugs had over .050 gap, and one was .080. I now have new ones gapped at .041.

Anyways, we finally hooked up tonight. I still have stock tires, been doing power mods first, and divorce w/kids makes a guy have to prioritize, OK? I am finally getting some Nitto DR 305/40-18's next week(hopefully):kaboom:. My buddy's got M/T's, so we are gonna do a 2nd gear roll to see if I can even hang with him, before we go from a dig in the future.

From the low roll, we are even out of the hole, but then I pull a length at the top of 2nd. 3rd gear is the same slow pull, so that by the top of 4th at 140 I'm 3-4 lengths out:??:.

OK, so something is not adding up; I know my car is running great and pulls like a freight train, but?

The caveat for the night is he is having some belt slip issues, and only had 5 out of 6 ribs on his belt:dw::rollseyes!

So, the stage is set for the rubber match; I am hoping to get the DR's beforehand, and we will get video.

 

[Riddla]

GT500 are beasts! But the Cobra is making more power so not sure on this one

 

[Na5ty 2V]

i would have thought the cobra would have pulled you.

 

[Qwk GT]

i would have thought the cobra would have pulled you.

+1


Good kill.

 

[thomas91169]

if those gaps are right on your plugs, thats astronomical. .08 is insane gap, hell even .050 is quite a bit for a stock boosted application, let alone a ported/pullied one. it would take an act of god for the spark to breach those gaps! You were probably getting a nice bit of spark blowout up top, your dyno numbers could very well be higher than what you posted. its true you can get more gap out of an iridium tip, but not much, were talking .005-.010 max.

if he is really having slip, thats why he didnt keep up. its been a while since i had a 03/04 or noticed, but dont they have 8rib belts..........

his slipping mixed with the possibility that your actual current output is higher than your last pre-plug change dyno venture, could be why the race went the way it did.

 

[karlton banks]

you got lucky. he's got more power and lighter....... he'll win every time.

 

[RealQuick]

What street tires do you have on there now? How is it a 600rwhp car with street tires doesn't just spin them thru 2nd and 3rd?

 

[littlejohn]

Yeah we both figured I would have had a hard time keeping up. I'm certain it's mostly his belt problems; we were equal on the bottom with me pulling on the upper rpm range, which is the opposite of what was expected.

My plugs were originally set at .028, but that is where I found the three plugs had the tips of the ground electrode burnt off to the point that the gap was that large, especially the one.

The race started from abut 3000 rpm in 2nd for me, and from that speed and rpm I hook good. We were just roll racing to see if I could even keep up until I get my DR's.

I fully expect to get pulled once he gets his sorted out, but it was still fun, and now he has to rebound and get me back:-D! It was hilarious, I'm sure he was as shocked as I was!

 

[RealQuick]

Yeah we both figured I would have had a hard time keeping up. I'm certain it's mostly his belt problems; we were equal on the bottom with me pulling on the upper rpm range, which is the opposite of what was expected.

My plugs were originally set at .028, but that is where I found the three plugs had the tips of the ground electrode burnt off to the point that the gap was that large, especially the one.

The race started from abut 3000 rpm in 2nd for me, and from that speed and rpm I hook good. We were just roll racing to see if I could even keep up until I get my DR's.

I fully expect to get pulled once he gets his sorted out, but it was still fun, and now he has to rebound and get me back:-D! It was hilarious, I'm sure he was as shocked as I was!

What brand and size of tire are they (the stock street tires)?

The reason I ask is because I and probably only around 500-550rwhp (7-8psi) max with my Turbo T/A, but I can break them loose from a roll in 3rd gear. I have 315 nitto DR's I am installing though.I run 275/40-17's street tires. Here is how it works for me with street meats:

1st gear roll - breaks tires loose before the gauge can even register boost (0psi)
2nd gear roll - breaks tires loose as soon as I hit 1-2psi
3rd gear roll - breaks tires loose when I hit 5psi
4th gear roll - hooks and made 8psi before I let off.

I would have thought that with the roots blower and 600rwhp you could easily fry 2nd gear, and that third may be an issue for you as well.

 

[kyl]

What brand and size of tire are they (the stock street tires)?

The reason I ask is because I and probably only around 500-550rwhp (7-8psi) max with my Turbo T/A, but I can break them loose from a roll in 3rd gear. I have 315 nitto DR's I am installing though.I run 275/40-17's street tires. Here is how it works for me with street meats:

1st gear roll - breaks tires loose before the gauge can even register boost (0psi)
2nd gear roll - breaks tires loose as soon as I hit 1-2psi
3rd gear roll - breaks tires loose when I hit 5psi
4th gear roll - hooks and made 8psi before I let off.

I would have thought that with the roots blower and 600rwhp you could easily fry 2nd gear, and that third may be an issue for you as well.

From 2nd gear at 3000rpm he is probably going 45mph, if he were to floor it there is not that great of chance they would break loose, he would probably get some spin though.

I'd be more worried about the shift into 2nd or 3rd, even at the stock level its not that safe.

 

[Blaine]

I still have stock tires,....

I almost stopped reading there.

The GT500 stock rear tires are Goodyear Eagle F1 SuperCars 285 45 18's AKA. Superslows. (This sized rear tires has no place on a 500 hp car.)

His car was messed up one way or another... he should of won with a tad more power + less weight... but drivers race still with him having an advantage which would of been much more of an advantage from a standstill.

In a stock GT500 with stock superslows you will spin bad in 1, 2, and some of 3rd. In one with 600 rwhp with superslows you will spin in 1, 2, and all of 3rd.

I won't race a civic with stock tires. Racing with stock superslows is just embarrassing. Every car review of a GT500 doing 0-60/1/4 mile with those tires is just irritating to watch. Don't do it.

If you lose traction shifting into 3rd... this crap can happen.

[ame="http://www.break.com/usercontent/2008/1/2007-Shelby-GT500-Crash-429828.html"]2007 Shelby GT500 Crash Video@@AMEPARAM@@http://embed.break.com/429828@@AMEPARAM@@429828[/ame]

 

[fastbacon]

its called know your car....he should feel it slipping and step off....then stand on it.......sux either way though..i bet that cobra was happy he was a tad slower haaha

 

[littlejohn]

One more caveat, he did have a 180 lb passenger I forgot to mention.

The stock Goodyears are absolutely disgusting from a dig; I've turned down lots of dig races for that reason. But for some reason with my stock suspension, the car transfers well from a low roll and hooks great. It was cool out, and we were on some really good dry pavement. On the 2-3 shift the car only chirped.

It's def. got torque; my dyno sheet shows 550 lb-ft torque at 2500 rpm, and I'm making 450 rwhp by 4000 rpm.

We were doing about 40 mph in 2nd, and with his 3.73's I thought we would be close off the start b/c I should have more torque to offset my stock gearing and the only slightly higher weight b/c of his passenger. I really expected him to pull me on the top.

I will get the rematch on video, and try to get shots from both cars; it's daylight up here until after 9 pm, so it's easy to get good daytime video.

 

[littlejohn]

What brand and size of tire are they (the stock street tires)?

The reason I ask is because I and probably only around 500-550rwhp (7-8psi) max with my Turbo T/A, but I can break them loose from a roll in 3rd gear. I have 315 nitto DR's I am installing though.I run 275/40-17's street tires. Here is how it works for me with street meats:

1st gear roll - breaks tires loose before the gauge can even register boost (0psi)
2nd gear roll - breaks tires loose as soon as I hit 1-2psi
3rd gear roll - breaks tires loose when I hit 5psi
4th gear roll - hooks and made 8psi before I let off.

I would have thought that with the roots blower and 600rwhp you could easily fry 2nd gear, and that third may be an issue for you as well.

There's a guy up here w/a turbo LT1 Camaro w/ 600 rwhp, that's been lightened up as well, who has the same problems. I've never raced him, but have heard he has terrible traction/transfer issues, and basically won't race from a dig. But from a 60+ mph roll he's very fast, supposedly even beating up on 750 street bikes!?

 

[07COBRAVENOM]

well with my gt500 with the stock shit tires i spin 1-part of 3rd its ridiculous im glad i put on my yokohamas they dont spin so bad

 

[SpdPilot]

You did not mention TQ rating for both cars. HP may be close, but I bet tq on the Shelby is much higher. and who cares about dyno numbers anyways. Real life is where it is at.

You won because you had the advantage. GT500 is heavier and also hard to get off the line. You went from a slow roll, which wipes out his advantage on you. Plus, the gearing of your car works to your advantage in the same situation. It should have been a close run. From a dig you would have lost.

But you beat him by a few car lengths, which should not have happened at all. So either he has a problem or can't drive his car.

Plus, dyno racing is not good. Could be variables in the dynos or even a Mustang dyno. I have seen the same car on the same dyno very by 50hp, depending on the temps, cool down, etc etc. I am really getting tired of the whole dyno racing. In my day, this would have been called Bench Racing.

You beat him, so be happy. Enjoy, let him try again some time.

 

[SVTullio]

Bro you wrote a few paragraphs of excuses and a mere sentence for the race.

 

[SVTDom]

wow i thought the cobra would have won! no affence to you...but a lighter cobra and it has more power lol.....good race, you must have a fast car if your beating a cammed whipple cobra!:beer:

 

[littlejohn]

I found out that buddy doesn't have the extra idler pulley to get better belt wrap, so I'm sure he's slipping on the top w/a worn belt.

Nitto DR 305/40-18s will be here Thursday; so we will be having the rematch soon. I'll def. get it on video, and we will prob. do both dig and roll races.

I fully expect to lose, but so what, its still fun! And giving a whippled/cammed cobra a hard time even if he is having problems was still good times lol.

 

[swoosh_stang]

I'm curious what the Shelby will make without the three bad plugs. I could buy 50 more whp with that problem fixed.