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Old 11-24-2017, 01:16 PM
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Default Drag racing setup

So, with the challenge car, im hoping for deep into the 12s or high 11s based on power to weight.

however, i know NOTHING about making an independent rear hook up on the strip. Always been a stick axle and leaf springs guy.

what is the proper setup to make a miata hook for sub 1.8 60 foot times? Other than wrinkle walls and skinnys up front.
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Old 11-24-2017, 09:10 PM
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Paging @miata2fast Troy. From what I recall, keep the cv shaft straight between the diff and wheel hubs, add spring in the rear to keep it from squatting when it transfers.

Don't use too tall a slick. Diameter is important.
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Old 11-24-2017, 09:27 PM
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Originally Posted by Dusterbd13
So, with the challenge car, im hoping for deep into the 12s or high 11s based on power to weight.

however, i know NOTHING about making an independent rear hook up on the strip. Always been a stick axle and leaf springs guy.

what is the proper setup to make a miata hook for sub 1.8 60 foot times? Other than wrinkle walls and skinnys up front.
To hook, you want no camber when under load, no deflection from the bushings so whatever the alignment is doesn't vary under load. An LSD that locks helps keep the car going straight if it does spin, so higher bias ratio = better, full locker = best. As mentioned axle's straight under load is best for durability. Depending on your trans/clutch, getting the launch control setup correctly will make a huge difference in your 60' times. Ideally you would leave under high boost and ride the clutch as needed to get the car rolling and not spin, and have enough power on the launch to not bog.
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Old 11-24-2017, 09:59 PM
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slicks, slicks are the only way you are going to run those 60's and not leave your drivetrain at the light. I have been to the track a few times with my Miata's and have always had **** wheel hop. I ran 24.5x9x13 slicks last time and it was a game changer. 1.8 60's and zero wheel hop, butter smooth 2nd gear burn outs. Those slicks were to big, 23x8x13 M&H's are the way to go.
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Old 11-24-2017, 10:16 PM
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For the record I ran a 1.8 60' with Hankook rs4's 225/45/15 on craptastic Megan coilovers. A better setup would be faster than a 1.8 60'.
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Old 11-25-2017, 01:03 AM
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Did you run an 1.800' 60 ft? Or a 1.89? How consistently could you run that time?

There is a big difference between doing a good 60' once, vs every single time you line up. Some yesterday bragged about running a 1.7 60', but they didn't post time slips, or what the actual time was, or how consistently his car ran that time he didn't post.
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Old 11-25-2017, 06:38 AM
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This wasn't Troy's best 60' but was his best ET of the night back in 2010. Naturally aspirated Miata with wrinkle wall slicks, IDK what size but I think they were 22 or 23 inches by 7 wide. He was launching at 5000+RPM if I recall correctly.
Attached Thumbnails Drag racing setup-img_1511609442528.jpg  
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Old 11-25-2017, 09:10 AM
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My car is setup for drifting and has **** Stance AL+ coils from 2008. I ran consistent 1.8's all day with tires way to big, and my alternator failed half after that 12.4 run and I was running 9.5 volts with out knowing for the rest of the day. If I went back with 23" slicks now I think I could run high 1.6's and get 11.9's .

To me the slicks are more about getting that smooth launch, having zero wheel hop is what its all about. I couldn't even do a burn out to warm and clean the tires on street radials.
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Old 11-25-2017, 02:55 PM
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So, how stiff are we talking about here?

how do you control the wheelhop?

rest makes sense.

since i will be boosted v6, gearing and tire size will probably need to be different, but we wont know that until the first test day.

and 1.8x 60 foot times are my goal. If i can get 1.5x, we should rrally be cooking. But sub 2.00 is my realistically expected results. With this being the challenge and all, we may not have the budget for perfect. But if i can learn what the optimal is, i can shoot for it.
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Old 11-25-2017, 03:07 PM
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Originally Posted by Dusterbd13
So, how stiff are we talking about here?

how do you control the wheelhop?

rest makes sense.

since i will be boosted v6, gearing and tire size will probably need to be different, but we wont know that until the first test day.

and 1.8x 60 foot times are my goal. If i can get 1.5x, we should rrally be cooking. But sub 2.00 is my realistically expected results. With this being the challenge and all, we may not have the budget for perfect. But if i can learn what the optimal is, i can shoot for it.
Bushings reduce deflection, which will reduce wheel hop. Control arm bushings, diff bushings, motor mounts all help reduce deflection in the drivetrain.
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Old 11-25-2017, 03:43 PM
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Bushings and **** only helps to a point, now the last time I went to the track on street tires I had 205 Dunlop dz102. I have yet today run it down the track on my 245 VR-1’s .

but I have V8R control arms with all Polly bushings, Delrin sub frame bushings and I tied my 6pt oem sub frame brace into the diff/ppf mounting point.

I remove the front sway and set the front suspension to max soft. You want the front to lift and transfer weight to the rear.

But it so far nothing has calmed the wheel hop except drag slicks. I used to go around the water box and launch the car at like 3500-4000 and ***** foot it out of the hole. Only could get high 2.1 60’s
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Old 11-25-2017, 04:05 PM
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Wrinkle wall slicks will prevent hop and absorb power pulses like a rubber band and release them smoothly. Practice higher and higher rpm launches until you reach the point where it doesn't bog at launch. That's what I remember. Slicks will still spin a little, but it is needed to avoid bogging to do it right.
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Old 11-25-2017, 08:14 PM
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Originally Posted by sixshooter
Wrinkle wall slicks will prevent hop and absorb power pulses like a rubber band and release them smoothly. Practice higher and higher rpm launches until you reach the point where it doesn't bog at launch. That's what I remember. Slicks will still spin a little, but it is needed to avoid bogging to do it right.

exactly, I was launching at 8k
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Old 11-25-2017, 11:34 PM
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Originally Posted by patsmx5
Did you run an 1.800' 60 ft? Or a 1.89? How consistently could you run that time?

There is a big difference between doing a good 60' once, vs every single time you line up. Some yesterday bragged about running a 1.7 60', but they didn't post time slips, or what the actual time was, or how consistently his car ran that time he didn't post.
First time at dragstrip and only ran 4 times, ran a 2.009, 2.015, 2.109, and a best of 1.854. So yea, was a fluke to get down to a "1.8" but I wasn't happy with any of my launches really, bogged twice, and 1 time I thought I slipped clutch too much, and the worst run my clutch ended up slipping in first and second. Was hot lapping it pretty good. Maybe was a well prepped track IDK, it never spun, no wheel hop. Car made 240 at 15PSI and I have it turned up a little for the drag.
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Old 11-26-2017, 01:33 PM
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Originally Posted by sixshooter
Wrinkle wall slicks will prevent hop and absorb power pulses like a rubber band and release them smoothly. Practice higher and higher rpm launches until you reach the point where it doesn't bog at launch. That's what I remember. Slicks will still spin a little, but it is needed to avoid bogging to do it right.
Wrinkle wall slicks that fit on stock 15 x 6 rims are easily available and cheap insurance on drive train. The question I have is what to safely run in the front. Bias ply skinnies want 4" rims. So it is either street radials on stock rims, or skinnies on some special purpose rims Like These?

Any recommendations for that?
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Old 11-26-2017, 01:44 PM
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I had thought about using two donut spares for skinnies. However, i can't put my finger on why it may be a bad idea.
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Old 11-26-2017, 02:09 PM
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Because they're totally meant to do 110 mph and then come to a stop very well.

You'll want to use soft walled slicks. Ask me how i know.
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Old 11-26-2017, 02:25 PM
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Originally Posted by Erat
Because they're totally meant to do 110 mph and then come to a stop very well.

You'll want to use soft walled slicks. Ask me how i know.
Soft wall slicks for the front? And how do you know.
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Old 11-26-2017, 02:38 PM
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It's obvious i was talking about the rear.
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Old 11-26-2017, 08:11 PM
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Just run your normal wheels up front. I ran skinnies because my friend let me use them, but I don’t think they are gonna make much difference.
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