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slobra281 said:
MPH sucks ass :) Traction won't effect mph that much. When I first got my car it had a 4.10 gear and a borla catback. Took it to the track and with 2.0-2.1 60fts I ran 14.3-14.5 @ around 95-96mph. Turns out that my IMRC had taken a ****. The only thing I can think of is that either you're shifting too low or the IMRC's aren't opening. After I replaced the IMRC control box the car picked susbstantially. Night and day difference.
HOw do u know if you imrc's are working correctly or not? I can feel them open up around 3200 or so but feels like my car is stalling or not wanting to go from about 5 grand and upward. I ran my cobra two weeks ago and could only manage a 14.4 at 100, is something wrong with my car or what? It did dyno 279 that day tho.
 

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jareds96svt said:


HOw do u know if you imrc's are working correctly or not? I can feel them open up around 3200 or so but feels like my car is stalling or not wanting to go from about 5 grand and upward. I ran my cobra two weeks ago and could only manage a 14.4 at 100, is something wrong with my car or what? It did dyno 279 that day tho.
I honestly really couldn't feel whether they were opening or not. I raced some of my friend who were mid to high 14sec cars and I either barely edged them out or lost. I then took it to the track and my trap speeds were like 93-95mph. I knew something was up so I took to the dealer and had my friend out it on the computer for me and sure enough it threw a code for the IMRC's.


And yeah, about 5000k upward it felt like a dog.
 

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slobra281 said:


I honestly really couldn't feel whether they were opening or not. I raced some of my friend who were mid to high 14sec cars and I either barely edged them out or lost. I then took it to the track and my trap speeds were like 93-95mph. I knew something was up so I took to the dealer and had my friend out it on the computer for me and sure enough it threw a code for the IMRC's.


And yeah, about 5000k upward it felt like a dog.


Well im gonna take it to a dealer tomm and let my friend put the pc on it and run the codes, cause my ces light is still on.. It came on after the install of my mils, go figure and gives a code for the O2 sensor up front everytime, so im afraid a computer scan wont help me but im gonna try it out tom. My trap times were 14.4 at 100. something and thats the best i had. I did dyno 279 but my HP on the chart was up and down way more than avg. My line across my dyno sheet is so jagged its not funny...
 

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slobra281 said:
MPH sucks ass :) Traction won't effect mph that much. When I first got my car it had a 4.10 gear and a borla catback. Took it to the track and with 2.0-2.1 60fts I ran 14.3-14.5 @ around 95-96mph. Turns out that my IMRC had taken a ****. The only thing I can think of is that either you're shifting too low or the IMRC's aren't opening. After I replaced the IMRC control box the car picked susbstantially. Night and day difference.
This is exactly right. I had my car tuned, and found out that my IMRC plate on the passenger side was not opening due to a broken cable that opens the plate. It was completely snapped in half. At that point my car was running low to mid 14s, with plenty of mods (slower than stock) so I knew something was very wrong. I dynoed at an amazing 220rwhp. After the IMRC cable was fixed, I dynoed at 278rwhp. The cables for your IMRCs run behind the intake manifold, and are covered in black electrical tape. Check to see they aren't frayed/broken and are operating properly. I bet they aren't. I ran a [email protected] with my IMRCs broken, check my sig. to see what a difference it makes.
 

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Discussion Starter #27
How much will it cost to have a dealer scan for codes? I'm kinda strapped for cash right now (its in the shop getting $3300 worth of body work done). The places here in Waco are pretty shiesty about even touching a Cobra (there aren't any SVT dealers here). Am I gonna have to take it to Austin just to have codes checked :rolleyes: (100 miles away). Lata

Clinton
 

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Well it'll be about $70 for the dealer to scan for codes. However, my car did NOT set off a code for the IMRC cable being broken. That is why I didn't know about it for so long. If you have a check engine light, you need to get that checked out (so long as your codes aren't due to removed catalytic converters). Otherwise, you shouldn't get a check engine light, or a stored code in the computer for a bad IMRC cable, or plate malfunctioning.
 

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Pat96Cobra said:


This is exactly right. I had my car tuned, and found out that my IMRC plate on the passenger side was not opening due to a broken cable that opens the plate. It was completely snapped in half. At that point my car was running low to mid 14s, with plenty of mods (slower than stock) so I knew something was very wrong. I dynoed at an amazing 220rwhp. After the IMRC cable was fixed, I dynoed at 278rwhp. The cables for your IMRCs run behind the intake manifold, and are covered in black electrical tape. Check to see they aren't frayed/broken and are operating properly. I bet they aren't. I ran a [email protected] with my IMRCs broken, check my sig. to see what a difference it makes.

well im gonna pull the codes tomm from it and see what i get. Im certain ill get a code for my o2 sensor cause i have everytime before, even tho i have mils out back. I dynoed 232 then 266 and 279 so maybe its working sometimes and not the other? How can i check it, just remove the tape and look?
 

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Okay, I pulled out my first time slip with my cobra:

14.57 @ 100.94
2.4 60'

how about a
14.7 @ 101.5
2.3 60'

the car went

13.6 @ 104, in stock trim, once i figured out how to drive it.

your problem could be a combination of both driving and or the track.
 

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That MPH is low... It sounds like your IMRC are working. But if it stumbles in the upper RPM's it sounds like you need to clean you IAC valve. ( I think that is the name) Also change the plugs to some copper ones and get some good new wires and air filter and even a new fuel filter. A lil PM goes along way! My first runs sucked also but with practice it will improve.

I see that all the time at the track. New people bring their cobra out and expect it to run like mine (see sig for times). They then get upset or thing something is wrong or they think I am spraying because they cant get out of the 14's. And that is their first time at the track. They dont know that last year alone I made over 125 passes. So practice, pracice, practice.

As far as the tires. They will hook.. (see my sig again :D) You just have to heat the heck out of um. I also have about 150 passes (and about 15K miles on them and it is time for new tires.

The times in my sig are befor the gears and chip. I am waiting on my BFG drags right now. :D

Good luck on getting it sorted out!!!
 

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Not what you want to hear, but here goes.

I ran my 96 cobra with the same mods as you(3.73's, K&N, BBK O/R h-pipe, 2 Chamber flows, and Kumho ECSTA 265/40/17's warmed up with a quick 1st gear burnout) and my result was almost the same. I ran 14.91 @ 96mph. That is with a 60ft of 2.36 sec and an altitude of 4800ft. I was shifting around 6900rpms and I was launching at about 1,000rpms.

So looking at your time I would say that either you were:

A) Shifting too soon(say 6100rpms or so)

B) You let off at the end of the track OR

C) Something is wrong with your car.


My times are far from even being decent at this altitude. If I were running 14.5's @ 96mph near sea level, then I would be even more sick to my stomach. I hope it is just something simple like "A" or "B" because that will be much cheaper to 'fix' than suggestion "C" ;)

Hope none of this post seems like a flame... I suck as a driver and just wanted to give you my input since we had the same combo's, tires, and similar times at two totally different altitudes.
 

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Could you guys who have learned how to drive your cobras by putting in some time at the track share some of your wisdom with the rest of us. I haven't gone to the track yet with my Cobra and when I do I would like to have an idea of what RPM to launch at and what rpm to shift at (7000?) Also do you guys stay in 3rd or go into 4th- I have stock gears and assume I could ride out 3rd. Any info would be greatly appreciated as my rice burner friends and buddies with 99 and 2000 GT's will rip me a new A$$ if my car runs like a dog. :eek:
 

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joey8656 said:
Could you guys who have learned how to drive your cobras by putting in some time at the track share some of your wisdom with the rest of us. I haven't gone to the track yet with my Cobra and when I do I would like to have an idea of what RPM to launch at and what rpm to shift at (7000?) Also do you guys stay in 3rd or go into 4th- I have stock gears and assume I could ride out 3rd. Any info would be greatly appreciated as my rice burner friends and buddies with 99 and 2000 GT's will rip me a new A$$ if my car runs like a dog. :eek:
Depending on starting line condition, the stickier it is, the quicker you release the clutch and higher rpm's. Rarely do I dump the clutch.....usually a 4000 rpm launch while riding out (in and out on the clutch) until my traction is good. Shift at redline.........and that means above 6800 on your stock tach. The stock tach is fairly accurate under normal acceleration, but under hard acceleration, the reading is a tad slow. Now shifting.....that's your choice.....I don't power shift.
Yes, if you have the stock 3.27's, then wind it through the traps in 3rd gear.
BTW, this is using street radials/drag radials.
 

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max said:


Depending on starting line condition, the stickier it is, the quicker you release the clutch and higher rpm's. Rarely do I dump the clutch.....usually a 4000 rpm launch while riding out (in and out on the clutch) until my traction is good. Shift at redline.........and that means above 6800 on your stock tach. The stock tach is fairly accurate under normal acceleration, but under hard acceleration, the reading is a tad slow. Now shifting.....that's your choice.....I don't power shift.
Yes, if you have the stock 3.27's, then wind it through the traps in 3rd gear.
BTW, this is using street radials/drag radials.
Pretty much the same thing here. But I was running Kumho's. Did a nice long 2nd gear burnout. (I know, I know, dont do long burnouts on street tires but you cant argue with consistand 1.97-2.04 short times with Kumho's.) But I launch about 2700 and feather the cluch. Shift as high as you can and with stock gears ride 3rd out! BTW I dont power/speed shift. But am pretty fast with a stick in my hand :D
 

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Stock:

Depending on the track condition, I used to launch the car around 2500 and slip the clutch until it hooked. I had to watch between shifts 1-2 and 2-3, there will be no 3-4 with stock gears, or the car would break the tires loose and the car would go side ways.
not a good thing!

with the addition of gears (4.30's) and Dr's (nittos 275-45's)

heat them *****es up with a good 2nd gear burnout.
run around 16 psi, probably could go a little lower.
launch 4000, probably could go a little higher.
dont dump the clutch, just let it out pretty quick.
shifting at 6,800, yes I do power shift, is there any other way?
make sure you are completely through the trraps at the end before you lift.

also, dont worry about your reaction time. concentrate on driving your car. this also means dont be racing you buddy's car or someone else's that you really want to beat. I made this mistake my first time out also.
 

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Discussion Starter #37
Ok, everyone keeps on mentioning where I am shifting. Well, I don't have an aftermarket tach, so I don't know exactly where I'm shifting. But I shift at about 6,800 from what my stock tach says. I don't powershift, 'cus my tranny is about to bite the dust. Am I shifting too low? Is my stock tach off maybe? I dunno :confused: ????????

Clinton
 

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You really should just be able to shift that thing by ear and seat of the pants feel. I didnt even pay much attention to my tach until lately and ran plently of 13.6 @ 104 stock. unless you are shift at 5500 i dont think this is you problem.
 

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Thanks alot for all the pointers. Im gonna run my friends Civic hatch w/ an Acura Integra GSR motor in it. It runs 14.5-14.3 and all these stories of 14 second cobras are scarin' me alittle. Ill try and put the tips to good use and kick some civic a$$.
 
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