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NONE OF IT
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Discussion Starter · #1 · (Edited)
I've been running my car at the track with 26x10.50x15 et streets, my best time so far has been [email protected] with a 1.7 60 ft with 10psi in the tires. My best trap was 119 with about 14psi in the tires. I have 4.11 gears, 6 speed manual, and my car is going through the traps in 4th gear at about 6100 rpm. Would it help if I switched to a 28" tire. I'm thinking my MPH would go down, but my 60ft may be better therefore making my et better. Let me know what you guys think. Thanks in advance. :beer:
 

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That tire swap will change your final drive ratio to 3.81, which at the same rpm will produce a higher MPH, it's hard to say what the net effect would be, the car may not ET as well but MPH better, which means nothing on the drag strip, a lot of torque can make the big tire work, but horsepower may favor the 26"ers, one way to find out, Try 'em !
 

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My shit always works sometimes
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just get rid of the worn out M/T DR's and get a new set of the 275 x 60's is a 28in tall tire it will work fine your going to want those on there when you spray it....
 

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NONE OF IT
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Discussion Starter · #5 ·
just get rid of the worn out M/T DR's and get a new set of the 275 x 60's is a 28in tall tire it will work fine your going to want those on there when you spray it....
I want to pick up the 28" et drags from Chris tomorrow, so I can try this on Saturday.
 

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I found this tire calculator but don't understand how it would work. http://www.f-body.org/gears/
That calculator shows your car running 121mph in 4th gear @ 6100 rpm, remember to input 1.1 as your fourth gear ratio, and use 3.81 as your final drive ratio if you're calculating the 28" tall tire, use 4.11 for the 26" tall tire.
 

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FUCK FOURLOKO!!
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Hey Eddie, have you tried the MT ET radials? 275/60-15

it is a 28" tall tire just in case you didn't know.
 

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Discussion Starter · #8 ·
Hey Eddie, have you tried the MT ET radials? 275/60-15

it is a 28" tall tire just in case you didn't know.
The tires I run on the street are the 275/60/15 tires, They are bald and I never had a chance to try them at the track, Chris Groves is selling a set of 28" et drags so I'm thinking about replacing the bald drag radials with the slicks.
 

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What RPM do you shift the car at? You're setup is damn close right now,but if anything you want to be crossing the traps at your redline or shift point, correct? Reason the calc shows 121 and your highest was 119 is most likely tire growth that is not taken into account with the calc.

What RPM does your car make its peak power? 6600 or so? You probably would be better off crossing the traps just north of your peak power RPM wise. All a 28" tire will do is DECREASE your RPM which I don't think you would want with the MS4. Are you spinning at all? If not I don't see a reason to go to a 28" until you start running out of RPM at the end. Then you need to go bigger so you aren't on the limiter.

Justin
 

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NONE OF IT
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Discussion Starter · #10 ·
What RPM do you shift the car at? You're setup is damn close right now,but if anything you want to be crossing the traps at your redline or shift point, correct? Reason the calc shows 121 and your highest was 119 is most likely tire growth that is not taken into account with the calc.

What RPM does your car make its peak power? 6600 or so? You probably would be better off crossing the traps just north of your peak power RPM wise. All a 28" tire will do is DECREASE your RPM which I don't think you would want with the MS4. Are you spinning at all? If not I don't see a reason to go to a 28" until you start running out of RPM at the end. Then you need to go bigger so you aren't on the limiter.

Justin
I have the limiter set at 6800, I shift at 6700. My car is doing 1.7-1.8 60 foots which I'm not happy with at all. Its not bogging, it doesn't feel like its spinning but it obviously is if I'm only achieving 1.7 60 foots.
 

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Lol lucky guess on the 6600. I think the bigger tires are probably goin to hurt because you won't get much above 5800 if you run 118. And that is nowhere close to the peak of that cam of yours.

Are you sure that your wheels aren't spinning inside of your tires? :confused5: I mean you are running 10 psi...
 

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:beatdeadhorse: driver mod !

j/k Eddie.. :seeya:
 

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Lol lucky guess on the 6600. I think the bigger tires are probably goin to hurt because you won't get much above 5800 if you run 118. And that is nowhere close to the peak of that cam of yours.

Are you sure that your wheels aren't spinning inside of your tires? :confused5: I mean you are running 10 psi...

will need the 28in tire for the spray.. f**k the n/a numbers.. :beer:
 

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If you're gonna spray it, go with the 28s. You could even juggle a tad on 28" tires height wise as a Hoosier is shorter than say, a Mickey.

+1 on 01MRMTransAm's statement, on motor the 28s are probably gonna hurt. I'm not sure how the drag radials would work, I've yet to see a local manual car do really well on the Mickey DRs.

Do the math, you might even work with a 27" tire.
 

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will need the 28in tire for the spray.. f**k the n/a numbers.. :beer:
Didn't know nitrous was in the plans. How big of a shot?

Even so, that's a lot of RPM left on the table as he sits right now. He can run around 128 as he sits right now. with a 27 133, and with a 28 138. That's at the limiter. If he runs very low 10s @ 135 or so then sure a 28 will be needed. But I don't know how much nitrous we're talking here.

If he got some drag shocks with some weight transfer to dead hook with 26s, he would be in good shape N/A. And damn close to it with the nitrous. The issue there is the dead hook.

I agree with buffhomer, a 27 might be damn near perfect. Or at least a very good tire for both.
 

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Didn't know nitrous was in the plans. How big of a shot?

Even so, that's a lot of RPM left on the table as he sits right now. He can run around 128 as he sits right now. with a 27 133, and with a 28 138. That's at the limiter. If he runs very low 10s @ 135 or so then sure a 28 will be needed. But I don't know how much nitrous we're talking here.

If he got some drag shocks with some weight transfer to dead hook with 26s, he would be in good shape N/A. And damn close to it with the nitrous. The issue there is the dead hook.

I agree with buffhomer, a 27 might be damn near perfect. Or at least a very good tire for both.

The real issue is the 7000ft DA and a N/A motor :nono:don't see the car trap'n 128 as it sits either.. on a perfect pass car may do 120 trap.. also the car is a T-56 and he doesn't power shift it.. so anywho.. the 27 tire is a good idea.:beer:. i used those one the cobra until it got over the 700rwhp mark.. 27x11.50 to be exact.. now the car has 28x12.50's :thumbsup:
 

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The real issue is the 7000ft DA and a N/A motor :nono:don't see the car trap'n 128 as it sits either.. on a perfect pass car may do 120 trap.. also the car is a T-56 and he doesn't power shift it.. so anywho.. the 27 tire is a good idea.:beer:. i used those one the cobra until it got over the 700rwhp mark.. 27x11.50 to be exact.. now the car has 28x12.50's :thumbsup:
I guess I should have clarified that. I meant that 128 is as fast as he could run with his current combo before he runs into the limiter.
 

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i think a 26" et drags with a big burnout would be awesome. You spin pretty bad. I think you should be able to pull a bottom 1.6 60 if you hook
 

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4th Gear
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I've been running my car at the track with 26x10.50x15 et streets, my best time so far has been [email protected] with a 1.7 60 ft with 10psi in the tires. My best trap was 119 with about 14psi in the tires. I have 4.11 gears, 6 speed manual, and my car is going through the traps in 4th gear at about 6100 rpm. Would it help if I switched to a 28" tire. I'm thinking my MPH would go down, but my 60ft may be better therefore making my et better. Let me know what you guys think. Thanks in advance. :beer:
mine on the 28 hooks and then i lose all rpm and it falls on its face, but that why i want to try 26 to see how it does!
 
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