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RIP Jason
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4,089 Posts
Discussion Starter #1
Well no one really answered this question in my brake post so I'll ask it here. How can i figure out my speed with my new gearing (4.88)? I'm still on 31's btw.
 

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162 Posts
4.88 and 31's??... hypertech comp programmer will help. You can try to find out what the closest fit is with the tires/gears. But my guess is that you aren't going fast enough to brake ANY speed limits, so I wouldn't worry about it until you got some tires on there haha

Let's have a project thread on yours, as it seems as if you are doing quite a lot of work. Looks good. Got any before/after's?
 

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RIP Jason
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4,089 Posts
Discussion Starter #3
Well nelson will be sending me an update soon but I just wanted to find out what I was doing now. Its such an odd setup that i really have nothing to go off of.

Well i basically got my truck the way it is. The only pics i really have right now are of it before the BL. Since I'm getting the whole thing repainted, lift, and interior eventually, I'll post stuff up as soon as it happens. Most of the work being done right now is fixin the POS.
 

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Kyle
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1,684 Posts
your crazzy, do you have a suspension lift?
 

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RIP Jason
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4,089 Posts
Discussion Starter #6
Blue Z Cowboy said:
hes got to, theres no way he could clear 31's
Haha very funny

No I don't have a lift but will be getting one soon. Read the sig damnit! I wasn't going to waste money and put 3.73 back in so I just put 4.88 in now.
 

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Assuming you have a .72 overdrive in the tranny and a tach to go off of

Highway Gearing Highway Gear Ratio 3.51
Engine Speed (RPM) at 40 MPH 1524
Engine Speed (RPM) at 50 MPH 1905
Engine Speed (RPM) at 55 MPH 2095
Engine Speed (RPM) at 60 MPH 2286
Engine Speed (RPM) at 70 MPH 2667
Engine Speed (RPM) at 80 MPH 3048
Engine Speed (RPM) at 90 MPH 3429
Engine Speed (RPM) at 100 MPH 3810

Using this calculator
Gearing Calc

You gonna give us a nice video finishing off the 31s before you put on larger tires?
 

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RIP Jason
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4,089 Posts
Discussion Starter #9
You are the man mprcd. I will smoke them after i rotate and put the 500 break-in miles on the gears. I probably won't have a video but I'll try and get some pics.
 

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Go down the interstate with a stop watch and set the cruise time your mile from maker to maker and take the number you get and divide it into 3660 and it should get you a close estimate.

Example. 45 secs to do a mile.

3660/45 =81.3333
 

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[>
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3,255 Posts
Grant said:
GPS. :read:
:word: If you have a friend with a handheld GPS, they are very good for speed. I know I have tested mine out in about 8 cars/trucks and it is right on the money.
 

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RIP Jason
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4,089 Posts
Discussion Starter #14
Well mprcd has me covered because i was following my friend and he was doing 55 and the RPM was dead on.
 
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