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Discussion Starter · #1 ·
Took the g8 out saturday for the first time with the tune an lt's, already have exhaust an vararam. Well long story short I left pretty dissatisfied, I got some mt radials on gto 17s. I had ran 13.3 @106 before at the same track with just the vararam an exhaust. Here's the slip, an imput to why it wouldn't 60ft under 2.0? I cut 2.0 60fts with the stock 19s so im confused the radials didn't. I tried stalling it up mashing it nothing changed.
 

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What were the temps and DA? These could possibly be factors. As far as the 60ft goes I'm not sure, I figure the radials would improve it.

Sent from AutoGuide.com Free App
 

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Discussion Starter · #3 ·
Temp was 75-80. Idk how to figure the da. The car was spinning hard on the 1-2 I have slips where the 1/8 mile time is 3 tenths difference with the same 60ft ...
 

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Mack
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Kyle you were flyin' down there. Nothing wrong with those numbers bro!!! :)
 

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Discussion Starter · #6 ·
Thanks mack! Troy I was hoping to get more out of it with the radials, I've seen people on here can get 1.9s out of the stock converter.
 

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Discussion Starter · #9 ·
So is a 1.9 60ft asking to much of the stock convertor? I thought for sure the radials would make it happen...Thoughts an imput?
 

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I think when I swapped to skinnies up front I was able to get down to a 1.93 on the stock converter.
I ran a 1.955 60Ft yesterday on stock converter and stock 18" RSA's. First run of the day on a nicely preped track. I would think a better tire would help a little but probably right, you need the Converter to get the RPMs up. According to my HPT log, a brake torque only got it up to 1500 RPM.
 

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For whatever reason, I ran better 60's on A/S tires with the stock 245/45/18 size tires, than what I ever did on 17" wheels and 275/40/17 MT's, at the same track.
With A/S it was 1.95 60's 8 out 10 times, never did better than 2.0 60's with the MT's and stock verter. The stock verter, at least in my case, didn't like to be brake stalled. some people have claimed good results using this technique, never worked in my car, with the aftermarket verter i'm launching at around 1500-1800rpm, and my 60 is down to 1.74-1.76.

I'll be trying M&H 255/40/17 tires once i'm done with my Toyo DR's, I still think the smaller 275/40/17 tire is hurting my launches, so I want to try a 28" tire instead and see what happens.
 

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I'll be trying M&H 255/40/17 tires once i'm done with my Toyo DR's, I still think the smaller 275/40/17 tire is hurting my launches, so I want to try a 28" tire instead and see what happens.
I really doubt that the smaller DR is hurting your launching. I run the 275/40/17 nt05r with a small 2600 stall and managed a 1.67 60' last time out. On the stock gearing in the rear end I think that the shorter tire helps the gearing on the back half of the track. Just my expireance though, definitely more than one way to skin this cat
 

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I really doubt that the smaller DR is hurting your launching. I run the 275/40/17 nt05r with a small 2600 stall and managed a 1.67 60' last time out. On the stock gearing in the rear end I think that the shorter tire helps the gearing on the back half of the track. Just my expireance though, definitely more than one way to skin this cat
Troy: What verter are you using? I'm thinking of going that route next. Did you end up changing gears?
 

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Troy: What verter are you using? I'm thinking of going that route next. Did you end up changing gears?
Precision Industries 2600 Triple Disk. Still on the stock gears, 2.92, but the shorter tire is the equivalent of swapping gears, as it does change the final drive
 

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What's that stall cost? It drive like stock on normal driving?
Got mine used, a hand-me-down from Rick. $700 installed.

It definitely doesnt drive like stock, but not in a bad way. When you accelerate it takes a little more gas and the RPM's stay around 2500 (under light acceleration) and they dont really drop when the car upshifts. But the shifts are super smooth, since the converter is absorbing a lot more of it. Once you get up to desired speed 45mph or greater you feel the slight bump of the converter locking up. Once shes locked and your above 45 its just like stock.

The launch is awesome now and Im digging the WOT lockup in 3rd @ 100mph, its like it grabs another gear and just goes into beast mode!
 

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maybe a little more? im not really sure. On the highway MPG is the same, im sure the in town milage has dropped some. On the way back from ECS in Darlington which was a mix of highway and country road driving I average 19.7mpg @ 65mph, and had several WOT passes in there also.

My vehicle line up is not set for fuel efficiency, built G8 and Z71 tahoe LOL, but o well, it doesnt bother me
 

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I really doubt that the smaller DR is hurting your launching. I run the 275/40/17 nt05r with a small 2600 stall and managed a 1.67 60' last time out. On the stock gearing in the rear end I think that the shorter tire helps the gearing on the back half of the track. Just my expireance though, definitely more than one way to skin this cat
I've been researching, and yes, 28" tire would be too much at my power levels, they should benefit those with huge FI power who think 1st is useless :)

I've found MT ET Street Bias (Tubeless) 26X11.50-17L, they're 26.5" tall, so that would be perfect for what i want to test.

I just don't understand why i was never able to get anything less than 2.0 60's with 275/40/17 DR's compared to my 1.94-1.95 60's with Conti DWS or Firestone Wide Oval in 245/45/18 tires, stock verter. I tried Nitto 555R and MT ET Street Drag in 275/40/17, same track, same day, no matter how i i launched the car, with the same results over and over.

It's way easier to launch with the verter and DR's, but i have the feeling my car would run better if i had the stock size tires, i know it probably doesn't make sense since in theory the smaller size tire acts like a taller gear for launching, perhaps the increased in mechanical torque is making my Toyo 275/40/17 DR's scream at the track and i'm not realizing this. They hook great on the street, and i'm running them permanently, fackers doesn't get baldy, and almost launching with my foot all the way to the floor. :secret:
 
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