Is my 3.55 gear killing my E.T?

Roket

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Ive got an 03 cobra, jlt, diablo, whipple 17psi, KB bap, 60lbs injects, 315/35/17 MT drag radials at 12 lbs of pressure, bassanni exhaust, no cats...oh, car tuned by Kurgan motorsports and made 595rwhp and 572 tq. Problem is i was at track today and best time was 12.02 at 115 with a 1.884 60ft time. Shifting at 6500rpm but i just barely, i mean barely shifted into fourth gear...like i was in fourth gear for like 10 feet..lol I thought i would want to be in the top end of fourth gear when crossing the end of the quarter! I understand that the fitsy 60feet make or break yout timed run...but....Do i need a 4.10 gear? I keep seeing cars with way less hp runnin tens..and i just got 12's. I know a good driver is needed..well lets just say this sint my first ride in a stang. It doesnt say what gear they are using...but what do u guys think? Oh, its got the IRS still too. Please help.
Thanks,
Roket...(I alao posted this on svt performance to get a wide variety of opinions)
 

IZZy

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shifting at 6k might help you a bit, something isnt right if you are only doing 115 out the back door, whats the 1/8" MPH?
 
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Roket

Roket

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94.37 mph izzy
 

IZZy

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94.37 mph izzy
your MPH is the same as mine last year, 94 at the 1/8 and 115-118 at the 1/4, with the power you made it should be higher.

Make sure your intercooler pump is working, if its not the iats are skyhigh and the computer pulls timing
 

Bob_Kurgan

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your MPH is the same as mine last year, 94 at the 1/8 and 115-118 at the 1/4, with the power you made it should be higher.

Make sure your intercooler pump is working, if its not the iats are skyhigh and the computer pulls timing
x2...u should pick up 28-30mph out the back door if everything is working properly.. if hte pump is not working, itll pull 2-8degrees of timing.
 

bmxer89

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Something is up there I pulled a 12.2 last weekend with just a exhuast, filter, and 315 nittos. I am pulling into 4th like barley before the finish line too, with that power thought you would be gettin into 4th way sooner
 

FuelSlut

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Ive got an 03 cobra, jlt, diablo, whipple 17psi, KB bap, 60lbs injects, 315/35/17 MT drag radials at 12 lbs of pressure...oh, car tuned by Kurgan motorsports and made 595rwhp and 572 tq. Problem is i was at track today and best time was 12.02 at 115 with a 1.884 60ft time. Shifting at 6500rpm but i just barely, i mean barely shifted into fourth gear...like i was in fourth gear for like 10 feet..lol I thought i would want to be in the top end of fourth gear when crossing the end of the quarter! I understand that the fitsy 60feet make or break yout timed run...but....Do i need a 4.10 gear? I keep seeing cars with way less hp runnin tens..and i just got 12's. I know a good driver is needed..well lets just say this sint my first ride in a stang. It doesnt say what gear they are using...but what do u guys think? Oh, its got the IRS still too. Please help.
Thanks,
Roket...(I alao posted this on svt performance to get a wide variety of opinions)

Something else is at work here. I wouldnt do gears, you will run out of 4th if you do them. Dana can confirm this. You will need to run taller tires etc. Plenty of people here doing 10.90's with 20-21psi good tune and supporting mods without gears.
 

hj16

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The 3.55s definitely aren't your problem, something else is lurking. I was going 115+mph with just a 2.93 and a tune.

Does it feel like its nosing over at all?
 
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Roket

Roket

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It feels a lil bit maybe when im at the top of second around 6300 6400 rpm, but it did feel like it sputtered a bit, might be im shifting too high.
 
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Roket

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I drove it this morning for a bit, not balls out, just around town and came home, popped the hood and noticed the coolant in the intercooler res was swishing around..so i assume this means its working. Now does it just run when the IAT gets high then it kicks on the pump, or does it run all the time? ALSO, if my BAP wasnt working, would i have no fuel pump activity period, or would the pump just act as if the BAP wasnt there?
 

Flatliner

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You need to log your runs if you have a laptop and xc2 or newer you will see exactly what's going on. Unfortunately, the only way to tell if a car is pulling timing is to see what the logs look like. Once you confirm that it isn't pulling timing, then you can go on to more like checking for belt slip, maybe wrong gap in plugs etc. Good luck.
 

gnxs

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You need to log your runs if you have a laptop and xc2 or newer you will see exactly what's going on. Unfortunately, the only way to tell if a car is pulling timing is to see what the logs look like. Once you confirm that it isn't pulling timing, then you can go on to more like checking for belt slip, maybe wrong gap in plugs etc. Good luck.
+1.

He should be trapping at least 10 mph higher. I assume the DA was decent this weekend and had nothing to do with it.
 
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Roket

Roket

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You need to log your runs if you have a laptop and xc2 or newer you will see exactly what's going on. Unfortunately, the only way to tell if a car is pulling timing is to see what the logs look like. Once you confirm that it isn't pulling timing, then you can go on to more like checking for belt slip, maybe wrong gap in plugs etc. Good luck.
Ive got the new Diablo programmer. It datalogs. Im just gonna call my tuner to have him give me a hand. Kurgan Motorsports...this guy named Bob works there, he knows a lot of stuff..LOL..

But thanks flatliner for the extra input..belt slippage seems to be top on my list.
 

Lightning Bob

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Roket

You didn't mention if you had an aftermarket heat exchanger, and or if you had significant cool down between runs. For best times, you need a cool air charge, and the stock system doesn't cut it even in the weather we had this weekend. As you may already know, your 60' times are also hurting you.
With my 03, I ran an 11.64 @117 with the same gears, IRS and a ported Eaton with only 520 to the wheels. This was with a 1.76 60'time on 275/40/17 Nitto's in much warmer weather. My $.02.
Good Luck with better times going forward.

LB
 
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Roket

Roket

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You didn't mention if you had an aftermarket heat exchanger, and or if you had significant cool down between runs. For best times, you need a cool air charge, and the stock system doesn't cut it even in the weather we had this weekend. As you may already know, your 60' times are also hurting you.
With my 03, I ran an 11.64 @117 with the same gears, IRS and a ported Eaton with only 520 to the wheels. This was with a 1.76 60'time on 275/40/17 Nitto's in much warmer weather. My $.02.
Good Luck with better times going forward.

LB

LB,
I actually talked to you at Byron..you were parked right next to me in the stage lanes..lol..i had the 03 silver cobra!!! I have an aftermarket heat exchanger yes. I had about 30 mins between runs. Im ordering a boost gauge since my stock one isnt very accurate, and gonna have Bob Kurgan give me a hand at what to look for when i datalog. Yea my 60ft sucks...havent raced it yet...but still getting used to the take off, but ill get it!!
 

Dana

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You need to get your 60 foot times down in the 1.50's to 1.60's.
Tires are important. Low 11's to mid 11's are possible on the ones you have.
You need practice and get used to the car.

Check to make sure the stock gear is still in place. 3.55
If you decide to change gears, don't go more that 3.73. You'll run out of motor if you do on 26 inch tires.

Based on your observation, it appears that the intercooler pump is working. It should turn on within a few minutes of starting the motor, normally. That can be changed in the tune to run all the time though.

Most of those cars that you are seeing run 10's with way less HP than you have are probably not 03 Cobras and almost certanly are carrying less weight than you are. These cars are HEAVY.

Finally, as mentioned above, datalogging may offer a clue if you still think there is a motor issue.
 
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Roket

Roket

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Hi Dana..but most the cars i see running the lower times are actually 03 or 04 cobras on svtperformance. I think the motor issue is gone dana, the pumps coming on like it should..just like u stated.
Like Bob Kurgan said, he thinks we have a blet slippage issue. When the belt was brand new and installed when the car was on the dyno, it did show a lil slippage at 6000 and up if i remember, but it was nothing to be worried about then, but now that the belt has some time on it, im sure its slippage. Ive ordered a better boost gauge so ill see how that does as far as boost goes. My stock boost gauge doesnt get over half way on the gauge, and when Bob tuned it, we were making on the high part of 17psi.
 

Dana

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Belt slip is always a possibility on these motors. I would recommend a manual tensioner, Reichart Racing is an example.

BTW, don't believe everything you read on SVTP.
 

gnxs

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Belt slip is always a possibility on these motors. I would recommend a manual tensioner, Reichart Racing is an example.

BTW, don't believe everything you read on SVTP.
:hail: ............especially the second part.
 

Aron

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You just need the driver mod!
 

FuelSlut

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belt slip is always a possibility on these motors. I would recommend a manual tensioner, reichart racing is an example.

Btw, don't believe everything you read on svtp.
+2
 
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Roket

Roket

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You just need the driver mod!
LOL..and this comes from a guy that had a giant sticker in his back window that said " BOTTLES ARE FOR BABIES"..lol
 

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