98 COBRA TROUBLE

SvT97

New Member
Sep 15, 2007
9
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ROCHESTER, NY
I HAVE A 98 COBRA VERT. LAST YEAR MY CAR WAS BONE STOCK EXCEPT FOR AN O/R H-PIPE. RAN A 13.74 AT THE TRACK... OVER THE WINTER I DID A SLP LOUNDMOUTH EXHAUST, BBK COLD AIR FENDER KIT, ACCUFAB SINGLE BLADE T/B, AND A CUSTOM TUNE FROM SCT... BUT BEFORE I WAS ABLE TO GO TO THE TRACK MY BUDDY GAVE ME A 90MM MASS AIR SENSOR, SO I PUT IT ON AND WENT TO THE TRACK RAN A 14.42 WHAT CAN BE WRONG ANY TIPS?ALSO I JUST TALKED TO HIM AND HE SAID THE MASS AIR SENSOR IS PROGRAMMED FOR 42LB INJECTORS, WOULD THAT CAUSE ME TO LOOSE THAT MUCH TIME? AND WHAT INJECTORS COME IN MY CAR STOCK?... SORRY FOR THE LONG POST JUST BEEN FUSTRATED MESSING WITH MY CAR
 
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The bbk cold air has been known to cause loss in hp (lol).
The Accufab, when was it made and by whom? (accufab drama)

If you put on a 90mm and didn't geta tune afterwards it sounds like your problem.

Most people swear by the stock TB BTW.

Did you start with the basics like plugs and wires? If they are the original
wires you might want to start there?

You have pulleys or deletes? Far more effective than any shiny cold air intake imho.

What was your tire pressure when you ran? What temps your tires?
You have a roll control to heat them up? How good is your reaction time?

You can go on and on really.
 
MY BUDDY GAVE ME A 90MM MASS AIR SENSOR, SO I PUT IT ON AND WENT TO THE TRACK RAN A 14.42 WHAT CAN BE WRONG ANY TIPS?ALSO I JUST TALKED TO HIM AND HE SAID THE MASS AIR SENSOR IS PROGRAMMED FOR 42LB INJECTORS, WOULD THAT CAUSE ME TO LOOSE THAT MUCH TIME?
FYI, Mass Air sensors aren't matched or calibrated to the injector. That's all done through programming of your cars ECU (computer). However, you do need to have the correct transfer function programmed into the ECU in order for it to provide proper calculations to the Mass air unit as it meters the incoming air. This must be done at the time of your custom tune as well and as already stated is likely the cause of your increase in ET's.

Setting aside the mechanical aspects of it, providing your 60ft time, MPH, elevation, outside air temperature and humidity would certainly go a long way towards helping us make a more informed decision to your problem. It would give us a better idea as to whether you're down on power, or just experiencing different track conditions from your run made the previous winter.

Oh and for god sakes kill the caps lock. My head is about to explode!!! :D
 
last year when i ran... it was a cool night about 50 degrees on street tires, last week when i ran it was about the same temp maybe a little colder... i was doing .520 lights and 2.1 60fts on my michalen street tires, which was better then last years 650 lights and 2.3 60ft. it seem like it is flatting out up top like from 5000-7000 rpms im feeling a loss of power
 
OK so i went back to my track last night with the stock mass air sensor and new plugs and wires... it was 95 degrees and humid I ran a 13.550 @ 104... any ideas how to get my time a little lower, i only beat my buddys turbo honda by 1/10th of a second... my "custom tune" was mail order through american muscle, do you think its worth the $300, to get it dyno tuned?
 
do you think its worth the $300, to get it dyno tuned?
It depends...is another 1/10th off of your ET worth $300 to you? If it were me, I'd save the custom tuning for when I chose to add any major mods. You've got to remember, you're running a N/A heavy assed convertible with only basic bolt ons against a turbo charged pip squeak of a car. The very fact you were able to outrun him as it it speaks volumes for your car.

Again...as for improving your ET, what was your 60ft time? If you want to really turn your car into an animal, look into a power adder and a gear swap for that 4V. These engines were made to rev and to extract the most out of them, you need to get it into its power band as quickly as possible.
 
That's good, especially for a vert. My 96 Cobra only had K&N, BBK L/T's, H pipe, DynoMAx and 4.10's and I ran 13.54@106MPH with a 2.2 60ft.

BTW...the stock throttle body is good for around 400HP. I'd sell that Accufab on Ebay, put the stocker back on, and spend put that accufab money toward a tune.

300 bucks is not worth 1/10 of a second.
 
seems to me every thing you did made the engine breathe better... i would look at your fuel system a lil bit.... one way to tell that your fuel system is letting you down and robbing power is that your temp will stay normal drivin around town but at the track when your beating on the car your engine will start to lean out causing the mixture to burn hot which leads to your engine running warm or overheating and worst cause detination
 
seems to me every thing you did made the engine breathe better... i would look at your fuel system a lil bit.... one way to tell that your fuel system is letting you down and robbing power is that your temp will stay normal drivin around town but at the track when your beating on the car your engine will start to lean out causing the mixture to burn hot which leads to your engine running warm or overheating and worst cause detination

No offence, but that's a pretty thin way to diagnose it. An engine is going to run hotter no matter how much fuel you're throwing at it when you're running it hard at the track. Load + RPM = heat.

Not to mention it's your EGT (exhaust gas temperature) that increases when running lean, not your coolant temps. He'd be better off reading his spark plugs after his WOT runs, or using a portable A/F ratio meter to determine his A/F ratio than he would anything else.

Either way, it seems that we've determined the Lightning/Cobra Mass air meter he used, without programming the proper function into the ECU was the cause of his lower ET's.