Need help

[1BADSNK]

Ok, I'm sorry if this is dumb to ask but here it goes. I was given some 28"x10.5 x 15 slicks. I want to find some el cheapo rims to play at the track. What do I need for a 15" rim on an 04 cobra? 15x10? 5 x ? lug. Also, I hope I dont need bead lockers. Sorry for being such a greenhorn. Thanks for any info/help!!:rolling:

 

[tktlwyr]

Man, that's a big tire! If you're a greenhorn, you might want to read up a little. It would help if you posted your mods, especially your rear end gear ratio and any power adders. Also, what tires are you currently running at the track and what gear/RPM are in/crossing at on the track.

 

[1BADSNK]

Man, that's a big tire! If you're a greenhorn, you might want to read up a little. It would help if you posted your mods, especially your rear end gear ratio and any power adders. Also, what tires are you currently running at the track and what gear/RPM are in/crossing at on the track.

Ya, I was told a 26" would be better but they still have a lot of meat & they were FREE. As far as gears the car is still stock. I've only run with the stock size & street tires. I have to shift to 4th just before I cross the finish line. The car is a 2004 Cobra with the following mods.

Stage 5 port with torq plate
2.76 upper
CAI
2400 MAF
pypes off road x-pipe
slp cat back
lfp dual pass heat exchanger
idler/pully kit
kenne bell boost-a-pump
Custom tune
520rwhp 500rwtq

Best time on street tires: 12.2 @120 2.2 60ft
I have 0 grip in first. Its 50/50 in second. Sometime she bites & other times not so much.:burnout:

Hope this helps

 

[tktlwyr]

Ideally, you want to be crossing in 4th near peak power. The 27s and/or 28s should keep you in 3rd through the traps. That's OK if you don't want to add more gear.

With that kind of power, you will want to start thinking about the rear end if you go to a slick, i.e. axles and locker, and would be the right time to add some gear. Also, while everything is apart, weld the axle tubes to the center section.

 

[01gtdude]

i have 28' hoosiers for my gt and i had to roll the fenders , as well as use a drag bag in the rr spring to keep the tire from hitting... i would be careful that could turn into a real bad time... as for wheels i've found for the money/looks/ and performance on a budget jegs sport stars do alright

 

[01gtdude]

oh man ... i just read your mods list... sorry i completely forgot i was in the termi section lol but anyway if you hook to hard on those stock half shafts they will spin in the boot and the car will go no where ( you will break them ) if your gonna be making normal trips to the strip and wanna use those tires i would invest in some of those level 5 half shafts .. or maybe a sra ...

 

[BADASS03SVT]

I thought 15s didnt fit on the IRS? might want to look into that first.

imo they are too big for the stock 3.55s and weight of that car. itll be like launching it with 3.27s

 

[racebronco2]

The 15's will fit with a little grinding on the spindle near the tie rod.

 

[04yellowcobra]

When I switched to the 28s I had to roll the fenders. As stated with some grinding on the tie rod you can get 15s on the IRS. A 15x10 will help improve your contact patch. The bolt pattern is 5x4.5". You will need lug nuts to fit the wheels that you purchase as well. As a precaution you may want to beef up the IRS if its stock (bushings, brace, shocks, etc). Once all this is done ... rev it up to about 4-5k RPM and dump the clutch! And pray that your clutch will hold the hook!

 

[1BADSNK]

Thanks for all the info guys. Maybe I will have to give the 28s away. I guess I should look for some 26s instead. I'm not hard core like most but would like to make 3 or 4 trips to the track & not spend most of my time just spinning. It would be cool to see what the car could do if I could hook for just ONE pass Great problem to have I guess......could be driving a snail instead.

 

[BADASS03SVT]

Thanks for all the info guys. Maybe I will have to give the 28s away. I guess I should look for some 26s instead. I'm not hard core like most but would like to make 3 or 4 trips to the track & not spend most of my time just spinning. It would be cool to see what the car could do if I could hook for just ONE pass Great problem to have I guess......could be driving a snail instead.

suspension suspension suspension

you issue is no weight transfer. prob running h&r springs or some lowering / handling spring. that makes it much harder.

 

[CobradaCableGuy]

suspension suspension suspension

you issue is no weight transfer. prob running h&r springs or some lowering / handling spring. that makes it much harder.

What do you mean makes it much harder? H&R springs give you harder firmer lauches or they are much harder to work with? I am planning on installing some H&R springs and some Nittos that I just bought cause I have alot of wheels hop. Same issue with me 1st gear spins like a steam train :burnout: not to mention 2nd gear wheel hop feels like the shafts are gonna snap. Down here in South Texas I have been to the junk yards and have seen around 25-30 junked Mustangs with SRA probably can get them for around $300 but kinda wanted to keep my IRS. :rockon:

 

[BADASS03SVT]

What do you mean makes it much harder? H&R springs give you harder firmer lauches or they are much harder to work with? I am planning on installing some H&R springs and some Nittos that I just bought cause I have alot of wheels hop. Same issue with me 1st gear spins like a steam train :burnout: not to mention 2nd gear wheel hop feels like the shafts are gonna snap. Down here in South Texas I have been to the junk yards and have seen around 25-30 junked Mustangs with SRA probably can get them for around $300 but kinda wanted to keep my IRS. :rockon:

those springs are just too stiff to get really good traction. you would be better off with stock springs over those "drag" wise.

you need the front to lift...even a little bit to put the weight on the rear tires to keep them planted. when guys with stiff corner carving springs launch...the car sits perfectly still and they do 1/8 mile bunrouts and run 13s @ 120.

 

[CobradaCableGuy]

those springs are just too stiff to get really good traction. you would be better off with stock springs over those "drag" wise.

you need the front to lift...even a little bit to put the weight on the rear tires to keep them planted. when guys with stiff corner carving springs launch...the car sits perfectly still and they do 1/8 mile bunrouts and run 13s @ 120.

So just stick with stock springs and struts and add some subframe connectors? I have a trade pending my Drag hoosiers 26x8x15 for some H&R's Should I just keep them get some 15x10 welds and see how they hook up. The slick carcass seems kinda hard but IDK You can see them here:
http://www.svtperformance.com/forum...261-new-hossier-racing-tires-26-5x8-0x15.html

 

[BADASS03SVT]

So just stick with stock springs and struts and add some subframe connectors? I have a trade pending my Drag hoosiers 26x8x15 for some H&R's Should I just keep them get some 15x10 welds and see how they hook up. The slick carcass seems kinda hard but IDK You can see them here:
http://www.svtperformance.com/forum...261-new-hossier-racing-tires-26-5x8-0x15.html

all depends if you want better track times vs better handling on the street. thats your choice.

 

[1BADSNK]

When I switched to the 28s I had to roll the fenders. As stated with some grinding on the tie rod you can get 15s on the IRS. A 15x10 will help improve your contact patch. The bolt pattern is 5x4.5". You will need lug nuts to fit the wheels that you purchase as well. As a precaution you may want to beef up the IRS if its stock (bushings, brace, shocks, etc). Once all this is done ... rev it up to about 4-5k RPM and dump the clutch! And pray that your clutch will hold the hook!

Ok cool, so I should be ok if I go with a 26.5". Thanks for the bolt pattern. What do I look for as far as the back spacing<<<:shrug:

 

[04yellowcobra]

15x8 = 5.5 backspacing
15x10 = 6.5 backspacing

I have never run a 15" wheel on an IRS so please do some research on which brands fit and which brands do not. I hear some brands you cannot grind the caliper enough to make the wheel fit.