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Discussion Starter · #1 ·
So I finally had the funds to purchase a set of 17” cobra rims and drag radials just for the drag strip. First let me give all the guys who have posted info about this cheap combo a big MUCHAS GRACIAS!! So I choose a new style to compliment my black vapor chrome SRT rims, they are 17x9 FR500 Mustang Cobra Anthracite wheels (here is the link http://www.americanmuscle.com/anthracite-fr500-wheel-17x9.html). I also ordered a set of 275/50/R17 M&H Racemaster drag radials from the same company. The tires were pricier than the Nittos but I read lots of good reviews about them so I spent the extra money. Just like others have posted, the center hub on the rims is a hair smaller than the SRT hub, so I used a 3” flap sanding wheel on a power drill to hone out the rim center. Took about 15 minutes on each rim, just be careful the rims are made of soft metal so don’t get too rough with it. I did not have to buy new lug nuts; the factory lug nuts worked fine and the set up didn’t rub or hit anything. So now to the good part, I hit the track on Friday and ripped back to back 12.9 @ 109 mph passes in hot 92 degree air with high humidity. I ran consistent 2.0 60’ when shaking down the new tires on a poorly prepped track. I lowered my air pressure down to 16 psi on my last pass and ripped a 1.9 60’ but I missed a shift and only ran a 13.1 @ 108 mph. I can’t wait for some better air and track prep because I know I can rip some 1.9 60’s which should put me into the 12.7 range. For reference last week my best 60’ time was 2.151 on the stock 20” rubber which hit 13.131 @ 109.10 mph. All the info about these rims on this forum made it easy to put together, seriously thanks guys. :icon_cheers:
 

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Thought about getting those too. Went with cobras and no modifications needed. And u know how they say cobra rims don't fit on the front? They're WRONG! Try it. My 03 cobras cleared the front calipers. Winter wheels perhaps...
 

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I run the Cobra rims but had to open up the hubs to make them fit on my R/T, now using them on my SRT with no issues. Congrats, now you just need some cooler weather and you should be able to whittle those times down.
 

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Discussion Starter · #4 ·
Yep feels like I am down by 30-40 HP with this hot air, I usually trap from 110 - 111 MPH in better air. One thing I found out is using the Drag Radials on hard launches really heats up the clutch. So I need to be careful hot lapping the car, it defiantly did not like that. I started having shifting issues, so I figure I need to let the clutch cool down about an hour between runs. Other than that, I’ll be ready for my next visit to the track. All in all I am happy with the results so far.
 

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Discussion Starter · #5 ·
Oh I forgot to mention another interesting observation about the drag radials, No Wheel Hop!! Just about every hard launch on the 20" factory tires would result in bad wheel hop. All of my hard launches (3K to 4K) on the drag radials did not create any wheel hop. Even when I would do a burn out to warm up the tires, no wheel hop.
 

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Thought about getting those too. Went with cobras and no modifications needed. And u know how they say cobra rims don't fit on the front? They're WRONG! Try it. My 03 cobras cleared the front calipers. Winter wheels perhaps...
The 2003 Cobra replica wheels from American Muscle P/N 10080 will not fit over the front SRT Brembos without spacers. You're saying that the actual stock '03 cobra wheels will? That would be good to know if they actually do. Are these stock '03 cobra wheels you're talking about or a replica?
 

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Yep feels like I am down by 30-40 HP with this hot air, I usually trap from 110 - 111 MPH in better air. One thing I found out is using the Drag Radials on hard launches really heats up the clutch. So I need to be careful hot lapping the car, it defiantly did not like that. I started having shifting issues, so I figure I need to let the clutch cool down about an hour between runs. Other than that, I’ll be ready for my next visit to the track. All in all I am happy with the results so far.
glad to hear i'm not the only one having shift issues after hot lapping in warm weather! this past weekend, i was running back to back a lot and had a nasty grind while trying to get it into gear in the pits and also it wouldnt go into 2nd while i was racing....i let her cool down and it was fine, but the metal on the hurst shifter was very hot! i hope nothing got damaged, but it did shift fine the next day.

i'm changing my trans fluid to some Royal Purple Synchromax before going back in hopes to lessen heat build up next time.
 

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Another nod to the theory that more traction combats wheel hop? Seems counter-intuitive, but the results seem to keep pointing that there is something here.
 

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Had to bore hub so guess they wouldnt fit front.
I had to use a 3/8" spacer to get them to clear the fronts calipers which then required longer studs (Ford F 250).
These were the American Muscle P/N 10080.
I saw no noticeable improvements in ET and the 25.5" tires up front were actually a little slower in MPH so I put the 20s back on up front.
 

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Discussion Starter · #13 ·
Yep, I like the way they look on the car. I received lots of compliments from my friends; one of my buddies is even considering buying 2 sets for his R/T so he can run 17’s all the way around. I will definitely say they are very well built, have a nice finish and should last a long time.
 

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So I finally had the funds to purchase a set of 17” cobra rims and drag radials just for the drag strip. First let me give all the guys who have posted info about this cheap combo a big MUCHAS GRACIAS!! So I choose a new style to compliment my black vapor chrome SRT rims, they are 17x9 FR500 Mustang Cobra Anthracite wheels (here is the link http://www.americanmuscle.com/anthracite-fr500-wheel-17x9.html). I also ordered a set of 275/50/R17 M&H Racemaster drag radials from the same company. The tires were pricier than the Nittos but I read lots of good reviews about them so I spent the extra money. Just like others have posted, the center hub on the rims is a hair smaller than the SRT hub, so I used a 3” flap sanding wheel on a power drill to hone out the rim center. Took about 15 minutes on each rim, just be careful the rims are made of soft metal so don’t get too rough with it. I did not have to buy new lug nuts; the factory lug nuts worked fine and the set up didn’t rub or hit anything. So now to the good part, I hit the track on Friday and ripped back to back 12.9 @ 109 mph passes in hot 92 degree air with high humidity. I ran consistent 2.0 60’ when shaking down the new tires on a poorly prepped track. I lowered my air pressure down to 16 psi on my last pass and ripped a 1.9 60’ but I missed a shift and only ran a 13.1 @ 108 mph. I can’t wait for some better air and track prep because I know I can rip some 1.9 60’s which should put me into the 12.7 range. For reference last week my best 60’ time was 2.151 on the stock 20” rubber which hit 13.131 @ 109.10 mph. All the info about these rims on this forum made it easy to put together, seriously thanks guys. :icon_cheers:
Yeah a 1.9 60' will put you at the 12.7 you are hoping for. I am running street tires (Nitto NT05's) and had a 1.93 60" and a 12.74 with a M6 392. I do have a Hopnot Total package kit, highly recommended.
 

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You guys don't need wheels and tires to get a 1.9x 60'. That's a waste of money. My RT and my 392 went 1.9x on stock rims and tires. My RT had F1s and my SRT has RSA's.
 

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You guys don't need wheels and tires to get a 1.9x 60'. That's a waste of money. My RT and my 392 went 1.9x on stock rims and tires. My RT had F1s and my SRT has RSA's.

I disagree. Once you custom tune a 392 and remove most of the tq mgmnt, it is very hard to hook consistently. Stock tire wear, temp and track prep will always be changing variables which the DRs will help to negate.
DRs should be your first mod if you race. If you have consistent enough 60’ times, you can use the track like a dyno (by using a DA Calculator) to determine if certain mods are helping or hurting.
DRs and a good tune to reduce tq mgmnt can put an A5 392 in the 11s. That would never happen on street rubber.
 

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Discussion Starter · #20 · (Edited)
Ok but is your car an A5 or M6? My SRT8 is a M6 and for the life of me could not do better than a 2.1 60' on the stock F1's. The DR's have definitely made hard launches productive and more consistent. Best mod for the track hands down.
 
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